# Buzzing sound after turning off the car??



## Spiffster (Jul 18, 2011)

You know after actually thinking about this for a minute... obviously this was the fan. Lets pretend this was never posted. I get the douche award for today. We'll just leave it at that.


----------



## NBrehm (Jun 27, 2011)

:3tens:


----------



## Crewz (Jul 12, 2011)

Spiffster said:


> You know after actually thinking about this for a minute... obviously this was the fan. Lets pretend this was never posted. I get the douche award for today. We'll just leave it at that.


LOL, there is a hum that the car makes after the vehicle is shut down. I heard it while washing my car and I thought I was hearing new construction or something in the area, but when I stuck my head down by the engine I could hear it clear as day. I started a thread asking what it is. If I recall correctly, it's the emission systems doing a leak check.


----------



## gfxdave99 (Feb 26, 2011)

I appreciate a man who can admit hes wrong. :goodjob:


----------



## dacruze (Jul 15, 2011)

Gfxdave99, you're correct, but in this case, i'm not so sure that he was wrong. I've heard mine do it too, and it definately doesn't sound like the fan!!! what i'm hearing sounds like a hgher pitch noise than the hummm of the fan. but what is it????? - Dan


----------



## FieroItaliano85 (Aug 5, 2011)

LOL doucher....classic!!!


----------



## audog (Apr 28, 2011)

dacruze said:


> Gfxdave99, you're correct, but in this case, i'm not so sure that he was wrong. I've heard mine do it too, and it definately doesn't sound like the fan!!! what i'm hearing sounds like a hgher pitch noise than the hummm of the fan. but what is it????? - Dan


I have the same thing, a high pitched noise, NOT a fan. It happens every time I open the hood, doesn't seem to make a difference if the car has been driven or not. It's faint, but noticeable, but goes away after a short time.


----------



## keveburd (Jul 15, 2011)

EDIT: Nevermind, I was thinking of something else.


----------



## swordfish (Feb 15, 2012)

I have the same issue ... half the time I park my car, I notice the buzz... sounds like an electric buzz of some sort. It starts off pretty quiet and gets louder. Then I get the key in the ignition, turn the car to on without starting, turn off again, and the buzz is gone. Anybody know what this is?


----------



## richard head (Feb 18, 2012)

I traced the sound close to the turbo. My theory is that when itis too hot at shutdown an electric pump circulates oil through the turbo to prevent coking, but I'm not sure.


----------



## SeanM402 (Aug 8, 2011)

I have heard this too! Sounds like a "tone" (if that makes any sense). I have heard this even when I haven't ran the car. I can just walk into the garage sometimes and it will make that noise.


----------



## XtremeAaron (Jan 22, 2012)

Anyone have some insight on this ? I noticed this as well.

Sent from my HTC Incredible 2.


----------



## Eightbelow (Mar 16, 2011)

I'm not sure what it is but I do know that it's normal. If I had to guess I'd say it's the theft system in the radio console doing stuff. It seems to do it when the cars off a few minutes/seconds after you close a door.


----------



## Johnny M. (Feb 24, 2012)

I heard the same noise. Sounds like the ABS pump. Driver side, lower firewall...


----------



## GoldenCruze (Dec 18, 2011)

I haven't heard it, but after reading here I'm going to be listening for it. Maybe the car is whining because you parked it...


----------



## silverram323 (Mar 16, 2012)

My car is also doing it, subscribing to thread, maybe someone will figure out what it is.


----------



## rbtec (Feb 3, 2012)

Mine does it too. Think it is normal.


Sent from my Autoguide iPhone app


----------



## Beaker (Mar 21, 2012)

Just had this high pitched sound today as well. Never heard anything like it from a car that is off. If it's normal fine but it sure freaked me out.


----------



## Chevy Customer Care (Oct 29, 2011)

Beaker said:


> Just had this high pitched sound today as well. Never heard anything like it from a car that is off. If it's normal fine but it sure freaked me out.




Beaker,
If you believe that this sound may not be normal I would suggest that you contact your local dealership and speak to them about this. They can look into it for you and let you know if it is normal or not. If you have any further questions please feel free to contact me.
Thank you,
Stacy Chevrolet Customer Service


----------



## Beaker (Mar 21, 2012)

No offense Stacy but taking a car to a dealer for a problem(if it is in fact a problem) that isn't persistent is a giant waste of time. They'll look at the car, start it, turn it off, say "Well we couldn't duplicate it", and send me on my way. Others are getting the noise so that tells me I'm not alone and that its possibly normal. Now if I hear it again I will try to record it with my phone, put it on youtube, and post it up here. Then someone, say in Chevy Customer Service, can research the problem and get back to us.


----------



## Toblin (Mar 28, 2012)

Count he as another one who hears what sounds like a small electric motor when the car engine is shut down. Not all the time, maybe once a week or so. The noise lasts about a minute. I'd like an explanation.


----------



## albow77 (Feb 18, 2012)

Mine did it this morning also. It was the first time in 2,500 miles. What the **** is it? I agree that taking it to the dealer is a waste of time and they are going to do nothing about it with out hearing it. It only happend once so far. It was diffentlly not the fan running but was coming from under the hood. Couldn't pin point it though


----------



## Beaker (Mar 21, 2012)

Update. Got the noise for a second time. Again was a warmer day, AC was on (turned off before shutting off car), car not driven hard.

Managed to get the phone out and record some video with audio of the noise. I'm not stating this is in fact a problem. It sounds from others that it is normal. But I just wanted to record it so Stacy can hear what we're talking about, take the video to GM, and we can find out exactly what this is.


----------



## albow77 (Feb 18, 2012)

That is the same noise that mine was making!!!! Sounds like a broken horn.


----------



## silverram323 (Mar 16, 2012)

Awesome Job, Stacy please get back to us about this weird tone after shutdown.


----------



## Beaker (Mar 21, 2012)

albow77 said:


> That is the same noise that mine was making!!!! Sounds like a broken horn.


You know, I have yet to even see if my horn works.


----------



## Dale_K (Jul 16, 2011)

Sounds like the system vacuum bleeding down, the way it slacks off toward the end but that's just a guess. I've never heard it on my LS.


----------



## Chevy Customer Care (Oct 29, 2011)

Thank you for posting the video Beaker, that helps. I am going to look into this and when I get an answer I will report it back to everyone. 
~Stacy Chevrolet Customer Service


----------



## garrettb1 (Feb 21, 2012)

Mine sat for at least an hour sunday then I washed it and herd the same noise.


----------



## Beaker (Mar 21, 2012)

Thank you Stacy. And by the way the issue has nothing to do with the different air intake. It happened before I put that on. 

I am pretty mechanically inclined and am at a loss as to what this is. Obviously something is running after the motor is turned off and to me it sounds like some type of electric pump. I just don't know enough about the car and the motor to know what it'd be. Is our water pump electric? If so maybe people's thoughts that its some kind of automatic protection for the turbo on warmer days is correct. But then I would think this "issue" would be more widely reported.

As I said, I am not at all driving the car hard. My car has rarely seen over 2,000 rpm. Mainly only to merge onto highways where accelerating slowly would be dangerous. Coming into my neighborhood I'm mostly coasting and never in boost.


----------



## rbtec (Feb 3, 2012)

My guess is that it is a pump to keep the turbo lubricated.


Sent from my Autoguide iPhone app


----------



## Toblin (Mar 28, 2012)

Thank you beaker! YEP!! That is the sound.


----------



## CruzeTech (Mar 23, 2012)

Im starting to like this car more and more everyday. Ive had my Eco a few weeks now and almost daily, I find something that someone thought of while designing this car. Some things completely amaze me and others are just plain cool. If this is in fact an electric pump to cool the turbo after shut down, someone is a genius. Ive owned a dozen or more forced indution cars and this would be the best thing to come out of the factory, that ive ever seen. 

Anyone else notice that turning the ignition key with the car running, the starter does nothing, unlike every other car Ive ever owned that was a key start, they grind to remind you that youre a dumb ass and the car is running. The Cruze does nothing turning the key with the engine running. pretty cool.


----------



## Chevy Customer Care (Oct 29, 2011)

According to my internal resources they were unable to pinpoint where the noise is coming from or what may be causing it. It is suggested that you take the vehicle into the dealership and have them see if they are able to pinpoint this noise. I understand that you do not believe it is an issue, but if you would like to know exactly what causes this noise the dealer is in the best position to diagnose this noise. I am sorry that I was not able to provide you with the information that you are all looking for. 
~Stacy Chevrolet Customer Service


----------



## Beachernaut (Mar 27, 2012)

I have noticed this same noise on multiple occasions with my Eco. I agree, it sounds like a small electric pump. 

I have not payed too much attention to it as I assumed it was normal. I'll pay a bit more attention and see if I notice any pattern (warm days, longer drives, shorter drives, etc).


----------



## Beaker (Mar 21, 2012)

Chevy Customer Service said:


> According to my internal resources they were unable to pinpoint where the noise is coming from or what may be causing it. It is suggested that you take the vehicle into the dealership and have them see if they are able to pinpoint this noise. I understand that you do not believe it is an issue, but if you would like to know exactly what causes this noise the dealer is in the best position to diagnose this noise. I am sorry that I was not able to provide you with the information that you are all looking for.
> ~Stacy Chevrolet Customer Service


So the GM Powertrain engineers who designed the car can't tell us what this sound is?


----------



## Beachernaut (Mar 27, 2012)

Beaker said:


> So the GM Powertrain engineers who designed the car can't tell us what this sound is?


+1 That doesn't give me a warm fuzzy feeling.


----------



## Chevy Customer Care (Oct 29, 2011)

Beaker said:


> So the GM Powertrain engineers who designed the car can't tell us what this sound is?



Beaker,
Unfortunately there is only limited information that can be gathered from your youtube video. It would be in your best interest to contact the dealer for this information. They are able to both hear the sound as well as look at the engine making it easier to pinpoint the location and cause of this noise. Again I do apologize for not getting you the answers that you are looking for. 
Thank you,
Stacy Chevrolet Customer Service


----------



## iKermit (Dec 13, 2010)

Beaker said:


> So the GM Powertrain engineers who designed the car can't tell us what this sound is?





Beachernaut said:


> +1 That doesn't give me a warm fuzzy feeling.


LOL you guys are hilarious. An engineer is not going to look at a youtube video and pin point what it is. There are lot's of components that make up the electrical system/whole engine that can make a "noise", hence you having to take it to the dealer. Common sense guys, don't be so harsh on GM for EVERYTHING.


----------



## rbtec (Feb 3, 2012)

iKermit said:


> LOL you guys are hilarious. An engineer is not going to look at a youtube video and pin point what it is. There are lot's of components that make up the electrical system/whole engine that can make a "noise", hence you having to take it to the dealer. Common sense guys, don't be so harsh on GM for EVERYTHING.


I agree, buy they should have an idea what it is.


Sent from my Autoguide iPhone app


----------



## chuck5330 (Oct 1, 2011)

So take it to the dealer and ask. Not a big deal really, jsut a few minutes of your time. Not that they would even charge you to diagnose a "noise". 

Thanks again Stacy for taking the time to ask


----------



## Beachernaut (Mar 27, 2012)

iKermit said:


> LOL you guys are hilarious. An engineer is not going to look at a youtube video and pin point what it is. There are lot's of components that make up the electrical system/whole engine that can make a "noise", hence you having to take it to the dealer. Common sense guys, don't be so harsh on GM for EVERYTHING.





chuck5330 said:


> So take it to the dealer and ask. Not a big deal really, jsut a few minutes of your time. Not that they would even charge you to diagnose a "noise".
> 
> Thanks again Stacy for taking the time to ask


Not trying to be harsh, my experience with GM has been good.

Taking advantage of the resources Stacy has available before making the 130 mile round trip to the dealer seems a lot like common sense to me.


----------



## Toblin (Mar 28, 2012)

_



My guess is that it is a pump to keep the turbo lubricated.

Click to expand...

_And my guess is that the GM engineers would be aware of that.


----------



## GoldenCruze (Dec 18, 2011)

I have tracked down what the source of that buzzing sound is. Today, I was sitting in the for few minutes after I parked it, thumbing through the owners manual. Clearly heard a buzz that lasted a few seconds. I instantly recognized it being the one of doors in the ventilation system operating. I can hear them run when the engine is idling, if I press a vent control. To verify what I heard, I turned the key to "Run" with engine off and started pressing the buttons. Yep, same sound!

You can verify for yourself if you wish. It took about two minutes for the sound to happen after I turned off the engine. I think it's the door that lets in outside air closing, that's the only one that makes sense.


----------



## Beaker (Mar 21, 2012)

I wouldn't think that door would take roughly 30-40 seconds to close all the way. Could be wrong though.


----------



## CruzeTech (Mar 23, 2012)

*Solved*

"The Honeywell supplied turbo itself is integrated into the exhaust manifold to minimize energy loss and lag, which helps with the engine's responsiveness. Coolant flow is maintained through the turbo bearing area after engine shutdown to prevent the oil from cooking and prematurely destroying the turbo."

AOL autos review


----------



## Beaker (Mar 21, 2012)

Fair enough. Then my question would be if coolant stays flowing every time we turn off the car, why don't we hear it always? Or is it only when the turbo is hot enough. Also people have said they've heard the noise even when the car was off and they just walked into their garage.

Again, not advocating this to be an issue. I just like to understand what it is.


----------



## CruzeTech (Mar 23, 2012)

Good possibility. If you're sitting at a stoplight for 30 secs to a minute turning into your neighborhood, that's all it may take for the turbo to cool down. As far as it running afterward, the engine gets even hotter after you shut it down. It's not getting cooled by anything. 

Now are the noises after immediate shutdown and an hour later even the same noise? Who knows. I'm convinced its the coolant running through the turbo after the car shuts down, which is completely genius.


----------



## silverram323 (Mar 16, 2012)

Ok guys, I can get the tone to duplicate indefinitely. I was looking at my wifes amp in the trunk, closed it walked to the front while looking at a piece of paper and then TONE, I reopened the trunk and timed it, 14 sec later the tone again.

I'm thinking it's a security thing.

Try it.......

Sent from my DROID X2 using AutoGuide.Com Free App


----------



## CruzeTech (Mar 23, 2012)

Do all models have the AMP? Oh, you mean it may be the security system.


----------



## silverram323 (Mar 16, 2012)

factory stereo speaker sucked so we added mtx speakers and a amp.

I also noticed if you just open a door, then close it, at 14 seconds the tone goes off. it has to have something to do with the security system


my 2011 has a tone and for my 2012 has a buzz definitely a different sound between the two.

Sent from my DROID X2 using AutoGuide.Com Free App


----------



## Toblin (Mar 28, 2012)

_To verify what I heard, I turned the key to "Run" with engine off and started pressing the buttons. Yep, same sound!_

Nope.

Did what you said and there was a brief but unsimilar sound, but not what the rest of us are referring too. Which is louder, longer, higher pitched and emanating from the engine compartment. 

Too many notices of such from too many owners to be an aberration. 

GM engineers?


----------



## CruzeTech (Mar 23, 2012)

Toblin said:


> _To verify what I heard, I turned the key to "Run" with engine off and started pressing the buttons. Yep, same sound!_
> 
> Nope.
> 
> ...


I answered the engine bay noise in my last post on the previous page. You can hear it right by the turbo.


----------



## SeanM402 (Aug 8, 2011)

I think the noise in the video has to do with the turbo. I have never heard this noise with my car. I am actually hearing a different noise not the buzz sound in the video but more of a "tone" sound. I think it might have something to do with the security system. I have heard it even when the car hasn't been ran for several hours and I just walk past it.


----------



## XtremeAaron (Jan 22, 2012)

Is this the sound some of you are describing ? 

https://www.youtube.com/watch?v=mTIEA2EgMiU&feature=youtube_gdata_player

Sent from my HTC Incredible 2.


----------



## mmdj808 (Apr 11, 2012)

I have noticed this same buzzing noise after my car was off for an hour, the day it happened I never drove over 45 MPH. It has only happened once and not as long as the one in the video posted here, mine was in short bursts and much more quiet but the same sound. Now instead of us asking everyone online we all need to get together and call corperate. I did so yesterday and of course they know nothing about this issue. I think this is a serious issue especially since there are a few cases of the Cruze catching on fire. If there are enough complaints about this maybe they will look into it faster. It seems lots of us have this issue and it does not seem normal to me. 800-222-1020, this is to corperate and tell them you want to report an issue with a buzzing sound when the car is off. It sounds to me like a horn that is muffled from the turbo area... thats how I described it to them. I have to go to a dealer today, but what good is it if it doesn't make that sound there. I will update this weekend with what is said to me on the follow up with corperate. But please, all of you need to call them as well so they know this is an issue.


----------



## tworightshoes (Apr 29, 2012)

I am going to agree with CruzeTech on this right now. I have less than 100 miles on mine, when I got home for the evening I heard the noise. At first I thought it was coming from someone's house....but, I have good hearing and knew it was coming from right in front of me. Stuck my head by the wheelwell and heard it pretty clearly. Opened the hood and REALLY heard it coming from the turbo area. It seemed to get louder for a few moments and then died out completely, like it was cooling itself. I'm not a mechanic by any means but I personally thought it was something to do with the turbo cooling as well. Until someone comes up with something else I will go with this assessment since it hasn't harmed anything....yet.


----------



## Dale_K (Jul 16, 2011)

I've got a theory that it's crankcase vacuum that sucks air past an oil seal. My car is a non-turbo so I can't test it myself but if I'm right you might get to stop (or actually not start) by unscrewing the oil fill cap at engine shut down. If that turns out to be right it could be a bad sign because it would mean one of the oil seals is weak.

This is totally guesswork on my part.


----------



## Eiolon (Feb 29, 2012)

I have the same noise. Had it since the test drive. I thought it was for the fan. When I go in to get my wind noise problem looked at I will ask them.


----------



## StoneCrab (Sep 14, 2011)

I think it is the fuel system pressurizing the injectors (or maybe depressurizing, hmm). Only happens after the engine is shut down, immediately after shut down. 

Odd thing is my wife's direct injected normally aspirated GM Equinox makes the exact same tone, only louder and much more consistently. It will even make the tone if you open a door on the car with the engine off, which leads me to believe it is the fuel system pressurizing itself readying to start.


----------



## Chevy Customer Care (Oct 29, 2011)

Eiolon said:


> I have the same noise. Had it since the test drive. I thought it was for the fan. When I go in to get my wind noise problem looked at I will ask them.




Eiolon,
I would like to you to keep me posted on the progress with your dealer. If you have any questions, comments or concerns please feel free to contact me.
Thank you,
Stacy Chevrolet Customer Service


----------



## Johnny M. (Feb 24, 2012)

Sounds like compression leaking down. i noticed the buzzing quite as the ticking slowed from compression releasing...


----------



## gt_cristian (Apr 7, 2012)

Could this be related to this post? 
http://www.cruzetalk.com/forum/34-1...noise-comming-daskboard-vents-engine-off.html

I hear a hissing/scraping noise comming from the daskboard vents with the engine off after driving the car for a few minutes. Since I turn on the engine and until I shut it off, the fan is on "OFF" and the temperature setting doesn't seem to matter. If I put the fan ON + cold setting for a sec and turn it off, the noise goes away.

I think is has to do with the AC beeing somehow on even though is doesn't show as on; when I turn on the fan the AC might go off for real and the noise dissapears.

Maybe is is related to this PI: PI0673..........Noisy A/C compressor when not "on" (not operating).


----------



## gt_cristian (Apr 7, 2012)

A similar post here:
http://www.cruzetalk.com/forum/25-s...cal-service-bulletins-tsb-lite-version-3.html

"







Originally Posted by *70AARCUDA*  ...new *GM Techlink *bulletin worth reading: *#PI0673*: *2011-2012 Cruze - A/C compressor noisy when not operating*.



I have that problem also. sitting inside the car sounds like slow metal to metal grinding,Turn on ac and its gone.​"


----------



## TwelveCruze (Nov 24, 2011)

CruzeTech said:


> Im starting to like this car more and more everyday. Ive had my Eco a few weeks now and almost daily, I find something that someone thought of while designing this car. Some things completely amaze me and others are just plain cool. If this is in fact an electric pump to cool the turbo after shut down, someone is a genius. Ive owned a dozen or more forced indution cars and this would be the best thing to come out of the factory, that ive ever seen.
> 
> Anyone else notice that turning the ignition key with the car running, the starter does nothing, unlike every other car Ive ever owned that was a key start, they grind to remind you that youre a dumb ass and the car is running. The Cruze does nothing turning the key with the engine running. pretty cool.



I feel the exact same way. I keep discovering things.

One more thing, my car made this exact noise just this week for the first time. I did have the AC on. I just assumed it was one of those things that I was discovering about the car. I am not worried about it, but I am surprised Stacy could not tell us what it is. My curiosity is piqued.


----------



## tworightshoes (Apr 29, 2012)

I haven't heard the noise since that first time so I'm not worried about it. And in reply to CruzeTech about the starter grinding noise - fortunately, my salesman told me about it while he was giving me the walk-through before driving it home. He said you can turn the key all you want while driving and it will not grind....cool stuff. I like this car a lot.


----------



## signals_91 (Nov 19, 2011)

I have heard this noise on 3 occasions that I have noticed since owning my 2012 1.4L MT Cruse LT since November. In all 3 times, the AC was never on. Upon turning the key to 'on' or accessory than back off, the noise is gone. Not sure I buy the story about some pump circulating oil to the turbo, because if the CPU is monitoring turbo temp and it's still hot, then it shouldn't go away (after turning the key on-off. The noise sounds like a digital high frequency square wave to me. I'm not worried about it, but it would be nice to know why it happens from time to time..


----------



## Beaker (Mar 21, 2012)

I've only heard it when I was running the AC and parked the car in my garage, turning the car off with the AC on. If I turn off the AC before I pull into my driveway, I never hear it. I'm one who always turns off his AC before shutting the car off though.


----------



## AkotaHsky (Feb 11, 2012)

This is actually the issue I have heard too. I always have my AC on (Welcome to Florida). I heard it twice in 3000 miles. I have tried to run the car rough, then park and turn it off and just being nice. I cannot replicate the issue. This leaves me to believe its not a cool down. My car is currently at the dealership. I will bring the audio clip to them when I pick it up. I have yet to hear from the dealership today


----------



## Pilsner73 (Apr 17, 2012)

My GF's new 2012 Eco is doing the same thing. Heard the same noise in the video posted a few pages ago right after the car was parked and turned off, let the car sit five minutes, took it around the block, parked and turned off, heard the same noise. Very annoying noise and at most it happened once before. 

Going to ask the dealer since it's a new noise and it doesn't sound right to my ears. If this was an expected noise I would think it would be mentioned in the manual just like the ABS check.


----------



## rbtec (Feb 3, 2012)

Whatever it is, it is normal. Seems that everybody has the same noise.


Sent from my Autoguide iPhone app


----------



## AkotaHsky (Feb 11, 2012)

I tried to have the tech listen to the noise and he blew it off.

He says the fans can turn on for up to 5 minutes after the car shuts down, but that is not a fan.


----------



## Pilsner73 (Apr 17, 2012)

rbtec said:


> Whatever it is, it is normal. Seems that everybody has the same noise.
> 
> 
> Sent from my Autoguide iPhone app


You may be right but just because a lot of people are having the same noise does not automatically make it normal. A lot of people are having noises that are actual issues (ac compressor, front suspension, steering wheel squeak) that are not normal and signs of an issue.
My take - this noise is very odd and loud enough that I would think GM would mention it in the manual just like they did the ABS self check if it was normal.


----------



## Pilsner73 (Apr 17, 2012)

AkotaHsky said:


> I tried to have the tech listen to the noise and he blew it off.
> 
> He says the fans can turn on for up to 5 minutes after the car shuts down, but that is not a fan.


If it's a fan I wonder if it's a fan motor going bad/locked up but still trying to turn. I would let Stacy know which dealer you went to and that they blew it off.


----------



## AkotaHsky (Feb 11, 2012)

Pilsner73 said:


> If it's a fan I wonder if it's a fan motor going bad/locked up but still trying to turn. I would let Stacy know which dealer you went to and that they blew it off.



Oh trust me.. Stacy can't help me anymore. I'm dealing with a District Rep from GM now. Check out my thread on the current battle:

http://www.cruzetalk.com/forum/9-ch...cussion-forum/6716-update-service-issues.html

Unless they can replicate it, theres not much to do. Then again, I dealt with a tech who was not to speak to customers cause of how much of an ass he is.


----------



## Pilsner73 (Apr 17, 2012)

AkotaHsky said:


> Oh trust me.. Stacy can't help me anymore. I'm dealing with a District Rep from GM now. Check out my thread on the current battle:
> 
> http://www.cruzetalk.com/forum/9-ch...cussion-forum/6716-update-service-issues.html
> 
> Unless they can replicate it, theres not much to do. Then again, I dealt with a tech who was not to speak to customers cause of how much of an ass he is.


Are there any other dealerships in the area for you? I had problems years ago and GM suggested a different dealership for warranty repairs, this solved a lot of my issues with the service experience. Hopefully you can get answers on the grinding shift noise and also the loud hum.


----------



## AkotaHsky (Feb 11, 2012)

Pilsner73 said:


> Are there any other dealerships in the area for you? I had problems years ago and GM suggested a different dealership for warranty repairs, this solved a lot of my issues with the service experience. Hopefully you can get answers on the grinding shift noise and also the loud hum.


Well, the Service Manager has offered to personally assist me and cut out the "Repair Tech" and "Repair Consultant".

The District Rep from GM is going to call me next week and see if I wanna bring it to a new Service Center. I am waiting till I fill my tank up to see if its still giving me problems.


----------



## dabluesman (Apr 22, 2012)

Beaker said:


> Update. Got the noise for a second time. Again was a warmer day, AC was on (turned off before shutting off car), car not driven hard.
> 
> Managed to get the phone out and record some video with audio of the noise. I'm not stating this is in fact a problem. It sounds from others that it is normal. But I just wanted to record it so Stacy can hear what we're talking about, take the video to GM, and we can find out exactly what this is.



My new 1LT has been doing this lately! I also would like to know what it is and if I should be concerned about it.


----------



## CruzeTech (Mar 23, 2012)

It's the coolant pump running coolant through the turbo after shutdown. The noise in the video is very distinct and I can listen to that noise on 20 different cars, and anyone would tell you that it's the sound of an electric pump. And since this car runs coolant through the turbo "after engine shutdown" there is no other explanation. Even if thats not what it was, the noise sounds nothing like there is anything wrong with the car.


----------



## gt_cristian (Apr 7, 2012)

This is a little different from what I hear. Inside the car I can hear a noise that sounds like hot water flowing through a pipe. It comes through the top middle vents only. With the fan off, if I change the temperature setting from cold to warm, the noise gets a little fainth, so I assume it must come from the AC.

And once I turn the fan on, with the AC on or off, the noise goes away.

I started hearing it after this winter. Last year I did not have this issue.


----------



## Pilsner73 (Apr 17, 2012)

CruzeTech said:


> It's the coolant pump running coolant through the turbo after shutdown. The noise in the video is very distinct and I can listen to that noise on 20 different cars, and anyone would tell you that it's the sound of an electric pump. And since this car runs coolant through the turbo "after engine shutdown" there is no other explanation. Even if thats not what it was, the noise sounds nothing like there is anything wrong with the car.


A question - Are you saying it's normal for turbo cars or all cars? The reason I ask is I have never heard that particular noise especially at the volume level on any other vehicles after they are shutdown but then again none have been turbocharged. I was standing eight-ten feet away from the vehicle when I first heard it and that was with the car outside with normal background noise. 

Now I am not saying the noise is not normal just that it's distinct and loud enough that it definitely catches one attention.


----------



## chevycruze2011 (May 25, 2012)

my car makes this noise too and i have the 1.8L. i think it may be a system check of some kind because it makes the noise after you turn it off and when you pop the hood. just my thoughts. i dont think its a fan or pump.


----------



## gt_cristian (Apr 7, 2012)

I have the same issue. I hear this scrapping or hissing sound with the engine on and stopped at a light. Also, when I brake and engine RPM goes up the sound get a little louder. 

I dont know where it comes from, but I know when it goes away. If I turn the A/C on, it goes away. So, while the AC is working the sound is not there at all. When I turn off the A/C, sometimes it comes back right away, sometime next time I drive the car.


----------



## Devilz (May 16, 2012)

CruzeTech said:


> It's the coolant pump running coolant through the turbo after shutdown. The noise in the video is very distinct and I can listen to that noise on 20 different cars, and anyone would tell you that it's the sound of an electric pump. And since this car runs coolant through the turbo "after engine shutdown" there is no other explanation. Even if thats not what it was, the noise sounds nothing like there is anything wrong with the car.


+1

This sound/noise is normal on cars with turbo.


----------



## dsevenem2 (May 29, 2012)

I think some of you guys arn't hearing the same sound as us turbo guys lol... its a little electric pump. Its a very distinct sound that I've only ever heard come from an electric pump. It's just pumping coolant or oil through the turbo.. it's like a simpler, factory turbo timer..... so it doesn't prematurely wear itself out.. And I'm sure it's got its own temp settings that tells it when it needs it and when it doesn't so its probably everytime or sometimes depending on driving conditions...

Now the door buzzing a/c sound or whatever other people are talking about idk what that crap is lol.... id get that looked at haha


----------



## RBC1300 (Jul 12, 2012)

Just bought new 2012 Black ECO Saturday. Sunday, I came back from a short errand and heard this noise. Thought it was house window fan or pool filter pump until I realized that it was under the hood. Turned key on to see if there was a notification but nothing. It went away after I turned the key off. Brought car in Monday to have it detailed and mentioned it to salesperson and service writer. They said it was probably the fan running after shutdown . I said that it did not sound like a fan but still felt foolish that I hadn't considered that. Next day, heard it again. Popped hood , made sure fan wasn't on and even gave it a spin to see that it moved freely.
Your video is exctly what I heard and where I heard it. How can I link it to send to my salesperson?. It sounds like some sort of warning or alarm buzzer. I want to know what it is so I know if I should be concerned or not.

Thank you.


----------



## rbtec (Feb 3, 2012)

RBC1300 said:


> Just bought new 2012 Black ECO Saturday. Sunday, I came back from a short errand and heard this noise. Thought it was house window fan or pool filter pump until I realized that it was under the hood. Turned key on to see if there was a notification but nothing. It went away after I turned the key off. Brought car in Monday to have it detailed and mentioned it to salesperson and service writer. They said it was probably the fan running after shutdown . I said that it did not sound like a fan but still felt foolish that I hadn't considered that. Next day, heard it again. Popped hood , made sure fan wasn't on and even gave it a spin to see that it moved freely.
> Your video is exctly what I heard and where I heard it. How can I link it to send to my salesperson?. It sounds like some sort of warning or alarm buzzer. I want to know what it is so I know if I should be concerned or not.
> 
> Thank you.


What ever this noise is it must be completely normal based on the number people that hear it, myself included. Personally I think it is some electric pump for the coolant to keep flowing to the turbo.....I am amazed that no service department has been able to identify this.


----------



## mrbuford (Jul 31, 2012)

*buzzing sound*



iKermit said:


> LOL you guys are hilarious. An engineer is not going to look at a youtube video and pin point what it is. There are lot's of components that make up the electrical system/whole engine that can make a "noise", hence you having to take it to the dealer. Common sense guys, don't be so harsh on GM for EVERYTHING.


>>>>kermit dont you think the guys at gm have ran these cars and tested them??
this is not the only person with a problem there many not to happy owners out here
all the stupid answers on this noise is a joke why the dealers dont know what it is they sell the car the tech line sayds they never heard of it give me a break they know what it is and also dont want to spend the money to fix this problem they rather we never buy their cars again I guess 
if stacey cant find the problem it must be normal ,,,hahahahahahahahahahaha
ok I believe you,, watch this and rember old man owns and drives this one
chevrolet cruze buyer beware - YouTube


----------



## spacedout (Dec 7, 2010)

mrbuford said:


> chevrolet cruze buyer beware - YouTube



Since GM has been so quiet as to the actual cause of this noise, could someone that has this happen try & pinpoint the exact location of the sound? It has been mentioned this could be an electric pump circulating coolant through the turbo if the temps are too high on shutdown, this makes allot of sense but if that's the case why wouldn't GM just verify that's what people are hearing. 

Also if that was the case it would seem the pump would be a replaceable part & not integrated with the turbo/exhaust so there would be part numbers involved.


----------



## mrbuford (Jul 31, 2012)

What ever this noise is it must be completely normal based on the number people that hear it
, 
Ok then if it is normal why doesent the mechanics at dealer know that
when they call tech assistance they say they never heard of it?????????????????????

myself included. Personally I think it is some electric pump for the coolant to keep flowing to the turbo...
ok everyone can think ,,,,,,,ok we want answers as to the noise


..I am amazed that no service department has been able to identify this
well its easy somone is telling someone to keep it hush hush.


----------



## jlove (May 16, 2012)

Mine does the same thing. It's not the fan. I took it to the dealer; they heard the noise and put in some sort of expansion valve, however the noise is still there. Apparently this poltergiest has been documented by the Chevy folks. The mechanic said that he contacted the tech folks (whoever they are) and they are the ones who said that the fix is the expansion valve. But--it isn't and my dealer wants me to bring it in again so they can troubleshoot it.


----------



## jlove (May 16, 2012)

I noticed that too! Now try this: Turn the key and let go immediately. You'll notice that the starter keeps turning anyway until the car starts. I'm not sure I like this, because if I release the key before the engine starts, it's probably because I saw some reason that I don't want the car to start. However, I'm with you on everything else. I really like some of the details that they've paid attention to and really enjoy driving it.


----------



## CruzeTech (Mar 23, 2012)

I already posted this earlier in the thread. Sorry Pilsner, I didn't see your reply to me. But here it is again for those that didn't read it earlier. 

"The Honeywell supplied turbo itself is integrated into the exhaust manifold to minimize energy loss and lag, which helps with the engine's responsiveness. Coolant flow is maintained through the turbo bearing area after engine shutdown to prevent the oil from cooking and prematurely destroying the turbo."

AOL autos review


----------



## jlove (May 16, 2012)

CruzeTech said:


> I already posted this earlier in the thread. Sorry Pilsner, I didn't see your reply to me. But here it is again for those that didn't read it earlier.
> 
> "The Honeywell supplied turbo itself is integrated into the exhaust manifold to minimize energy loss and lag, which helps with the engine's responsiveness. Coolant flow is maintained through the turbo bearing area after engine shutdown to prevent the oil from cooking and prematurely destroying the turbo."
> 
> AOL autos review


I could buy this as an explanation if the folks at my chevy dealer had said this, but they didn't. They said "We don't know." I also don't think it explains why it "fades out" instead of "shutting off." It it was a pump that was moving the coolant, wouldn't we hear the noise at the same volume until the pump shut off?


----------



## CruzeTech (Mar 23, 2012)

Does it matter why it fades off or just shuts down? It still accomplishes the same thing. When you fill a glass under a faucet do you fill it at full speed, then slow it down when it's almost full? There really is no explanation for it. 

And 95% of dealer mechanics don't drive what they work on. It's a job for most of them. Same reason I go to Best Buy the same day a new MacBook Pro comes out. And neither the guy spending $2,200 on a laptop nor the Apple kid selling the thing have any idea a new one was just announced an hour ago. Why? Because they don't care. 


Sent from my Autoguide iPhone app


----------



## Subic (May 6, 2012)

jlove said:


> I could buy this as an explanation if the folks at my chevy dealer had said this, but they didn't. They said "We don't know." I also don't think it explains why it "fades out" instead of "shutting off." It it was a pump that was moving the coolant, wouldn't we hear the noise at the same volume until the pump shut off?


Last two sentences. 
Not necessarily.
It could be a variable speed motor controlled by temperature. As temperature decreases motor RPM would also. Would sound like "fades out".


----------



## RBC1300 (Jul 12, 2012)

Bought the car last month. Heard the noise the 2nd day. Sent a link to Beaker's video to the service manager because it showed exactly what I heard and where it is coming from. She said that she checked for a service bulletin on it but found nothing and to bring the car in. I'm not ready for that wild goose chase yet. It has done it about three more times. We were in a parking garage last time so I popped the hood and my wife listened to it too. We have both worked around a lot of machinery and both agree that it sounds like an audible warning buzzer. I turned the key on, then off and it stopped. I know that it is not the fan and I am having trouble with the coolant pump theory because it doesn't sound like a pump and it is too random. I've shut down the car on 95 degree + days when you think it would be calling for cooling. And the dealer should be familiar with it if it is a normal function. I'm really surprised it hasn't been identified yet.


----------



## CruzeTech (Mar 23, 2012)

95 degree days don't really have anything to do with how hot the oil inside the engine is getting. It's using a coolant pump to flow coolant through the turbo to cool the oil on the impeller shaft and prevent oil "coking" it's a built in turbo timer.


----------



## Christrit (Jun 23, 2012)

It has happened on my Cruze two times since I've owned it (2 months)... If this is the case, then why has it only happened twice. Shouldn't it happen every time I park it?


----------



## jdubb11 (Mar 14, 2012)

Joining the electric buzzing sound club. Heard it twice today after shut down for about a min and a half till it faded away. I have video on my phone i can post when i get home. Like others id like to have dealer verification of what and why the sound


----------



## jstoner22 (Aug 21, 2012)

so has there any been confirmation from *GM *or a *dealership* as to what this is?

noticed it from day one on my 2012 ECO. I thought it was something to do with the electric grill shutters at first, but really have no idea.


----------



## jdubb11 (Mar 14, 2012)

i showed them a video on my phone of this sound and i got the "never heard that before, bring it in when it does it again". mine only seems to do it on hot days(over 90) and use of the air. so i prob wont hear this till june or july next yr.


----------



## Tjax (Sep 14, 2012)

http://youtu.be/oYEKZPR-uTw

Wow thought I would post my unique sound tithe forum and saw quite the extensive thread already on it. Luckily I also grabbed a vid of mine. My original thought was it sounded like pressure leaking out and it would almost seem like it was because the sound slowly faded away after a few min. BUT normally if it was pressure leaking out the tone would get deeper as the pressure became less an that was not the case for me. Totally baffled by this. If I experience it again I will pinpoint it for everyone.


----------



## Tjax (Sep 14, 2012)

Also the noise seemed to be coming from the Passenger Side of the Engine Compartment and it was in fact quite loud. I'll ask a few guys at work who know more about the turbo motors if its something they recognize. I have only used the AC once in the last 7 days I've owned the car but I am pretty sure it was that night. IF this is the case I may be able to replicate this by getting my car up to operating temperature, stopping an shutting the engine off for about 5 min an then getting back in, firing it up with the A/C ON and driving a SHORT distance like a .5 mile or so, shutting the vehicle off and checking for the noise. If I recall correctly the ambient air temp that night was about 70°f.


----------



## Dale_K (Jul 16, 2011)

gt_cristian said:


> I have the same issue. I hear this scrapping or hissing sound with the engine on and stopped at a light. Also, when I brake and engine RPM goes up the sound get a little louder.
> 
> I dont know where it comes from, but I know when it goes away. If I turn the A/C on, it goes away. So, while the AC is working the sound is not there at all. When I turn off the A/C, sometimes it comes back right away, sometime next time I drive the car.


That is a known issue with the Cruze A/C compressor. My dealer has replaced mine under warranty for the same problem. He said they've done several.


----------



## jblackburn (Apr 14, 2012)

Since my dealer replaced the expansion valve in my Cruze, I haven't heard this noise since.

Expansion valves can makes weird noises...my old Jeep made a slurping sound when it turns off if the AC had been running. I could see where it might be causing that noise in the Cruze too.


----------



## oMAHONEYo (Mar 23, 2012)

I feel like this doesn't really have anything to do with the turbo, mostly because my LS makes the same sound... and as much as I'd love to pretend... I don't have a turbo!


----------



## Tjax (Sep 14, 2012)

oMAHONEYo said:


> I feel like this doesn't really have anything to do with the turbo, mostly because my LS makes the same sound... and as much as I'd love to pretend... I don't have a turbo!


Lol. So are you saying your car makes the same high pitched noise that mine does in the vid i posted a few posts back(post #104)? If so that very helpful.


----------



## jdubb11 (Mar 14, 2012)

yup, thats the sound, and its comes from the passenger side of the car. the morning i brought my car in to have this looked at it was 55-60 outside. i used the air(and froze my but off) all the way to the dealer(10 miles) and when i got there of course it didnt make the noise. i used the air alot this summer as you cant get cool air to blow in from outside using the vent even when its 60-70 outside. i only heard it on the hottest days (90+). kinda ticked me off that even with the video they wouldnt look at it since it wasnt doing anything that day. if it is that expansion valve, i wonder if it is doing any harm to the car driving it with it operating like that at times.


----------



## Chevy Customer Care (Oct 29, 2011)

jstoner22 said:


> so has there any been confirmation from *GM *or a *dealership* as to what this is?
> 
> noticed it from day one on my 2012 ECO. I thought it was something to do with the electric grill shutters at first, but really have no idea.



jstoner22, 
I see that you're from Canada and wanted to let you know that should you wish to contact Customer Service for your region, GM of Canada can be reached at 800-263-3777 (Hours: M-F 7:30am - 11:30pm, Sat 7:30am - 6:00 EST). 
Sarah (Assisting Stacy), Chevrolet Customer Service


----------



## Chevy Customer Care (Oct 29, 2011)

All, 
We are certainly available to anybody who is working through getting this concern checked out with their dealership. Please contact us via private message with more information and we will look into your situation further (include your name, contact information, the last 8 digits of your VIN and mileage, and the name of your dealership). 

Sarah (Assisting Stacy), Chevrolet Customer Service


----------



## oMAHONEYo (Mar 23, 2012)

Tjax said:


> Lol. So are you saying your car makes the same high pitched noise that mine does in the vid i posted a few posts back(post #104)? If so that very helpful.


Yep! My dad was in the garage the other night and was a little concerned... told him it was 'normal' haha. Mine's a 2012 LS, so.. we can at least eliminate that it's due to the turbo.


----------



## rmass09 (Apr 17, 2011)

Mine seemed to be making the same noise today, not as loud as in the video though, all I had done was move the car 50 feet into the garage, didn't last long though.


----------



## RPHenry250 (Dec 8, 2011)

My 2012 LS makes that noise, also.


----------



## obermd (Mar 3, 2012)

I heard this from my ECO yesterday. It's definitely not the turbo as the sound was coming from the front of the engine bay and the turbo is in the back of the bay. It sounded like an electric motor so I wonder if there's a cooling system pump at the front of the car. My Montana also did this and is was the engine coolant system circulating coolant to eliminate any hotspots.


----------



## jblackburn (Apr 14, 2012)

obermd said:


> I heard this from my ECO yesterday. It's definitely not the turbo as the sound was coming from the front of the engine bay and the turbo is in the back of the bay. It sounded like an electric motor so I wonder if there's a cooling system pump at the front of the car. My Montana also did this and is was the engine coolant system circulating coolant to eliminate any hotspots.


The turbo is at the front, right under the heat shield.

The Cruze's engine is flipped around (like a Honda) with the exhaust at the front. I'm not sure why, but it makes access easier. The turbo was a real PITA to get to on my Volvo.

I kinda wonder if it's the same thing though. I'm guessing you weren't running the AC (unless you were using defrost, were you)?


----------



## Dale_K (Jul 16, 2011)

My LS doesn't do this but my theory is it's some kind of crankcase pressure issue and the sound is air sucking in (or blowing out) at a seal. If I'm right it ought to stop instantly if you pull the dipstick or remove the oil fill cap.


----------



## herchevycruze (Aug 7, 2011)

My Eco has also done this since I first got it, it now has 32k on it. I have noticed it all year around and the noise lasts for about a minute after engine off and key out and is obviously coming from engine compartment. I never took it to the dealer because it's an intermittant issue and I figured they would never be able to duplicate it.


----------



## obermd (Mar 3, 2012)

I had the defrost on so the A/C condensor was most likely running. 

If the turbo's in the front, what is that softball sized item on the exhaust tubing in the back of the engine bay?


----------



## jblackburn (Apr 14, 2012)

obermd said:


> I had the defrost on so the A/C condensor was most likely running.
> 
> If the turbo's in the front, what is that softball sized item on the exhaust tubing in the back of the engine bay?


That may be evidence to support my hypothesis that it's the expansion valve. I've only heard it myself a few times though. 

Electronic Throttle body? Plastic intake manifold is in the back of the engine, and the turbo and wastegate actuator are here

.









Sent from my iPhone using Autoguide.com App


----------



## Beaker (Mar 21, 2012)

jblackburn said:


> The Cruze's engine is flipped around (like a Honda) with the exhaust at the front. I'm not sure why, but it makes access easier. The turbo was a real PITA to get to on my Volvo.


I don't think I've ever seen a horizontally opposed 4 cylinder with the exhaust at the rear of the motor. I believe it largely has to do with the direction the motor torques when revved.


----------



## jblackburn (Apr 14, 2012)

Beaker said:


> I don't think I've ever seen a horizontally opposed 4 cylinder with the exhaust at the rear of the motor. I believe it largely has to do with the direction the motor torques when revved.


Horizontally opposed like a beetle? 

Inline-4, here you go though


----------



## Beaker (Mar 21, 2012)

Sorry. Wrong term. I just meant any inline-4 that is horizontal to the car as opposed to straight in line with it.


----------



## Chevy Customer Care (Oct 29, 2011)

herchevycruze said:


> My Eco has also done this since I first got it, it now has 32k on it. I have noticed it all year around and the noise lasts for about a minute after engine off and key out and is obviously coming from engine compartment. I never took it to the dealer because it's an intermittant issue and I figured they would never be able to duplicate it.


Hello herchevycruze, 

We certainly understand your thinking about not getting this checked out with your dealership as you state it's intermittent. If you do decide to go in before your warranty comes up (or after), be sure to let us know as we're available to do any necessary follow up with your dealership. 

Sarah, GM Customer Service


----------



## Formula001 (Dec 31, 2012)

I have bad this buzzing since I bought in August (2012 Eco) it has been lasting longer and longer after I turn the car off. Today I parked the car after work came back out side 10 minutes later to empty some things out and I heard it. Came back out 2 HOURS later and it's still making the buzz in a softer tone. Has anyone had any luck finding out what this is? It just seems like this has to be taking power from the battery. I don't understand, and of course when I brought it to the dealer when I had my first oil change it didn't make the sound.


----------



## Chevy Customer Care (Oct 29, 2011)

Formula001 said:


> I have bad this buzzing since I bought in August (2012 Eco) it has been lasting longer and longer after I turn the car off. Today I parked the car after work came back out side 10 minutes later to empty some things out and I heard it. Came back out 2 HOURS later and it's still making the buzz in a softer tone. Has anyone had any luck finding out what this is? It just seems like this has to be taking power from the battery. I don't understand, and of course when I brought it to the dealer when I had my first oil change it didn't make the sound.




Formula001,
I would like to apologize for the issues that you have experienced with your Cruze. I do understand your concerns with this. I would be happy to look into this further for you. If you would like me to look into this please send me a PM with your VIN. Either way, please keep me posted on this and if you have any questions please feel free to contact me anytime.
Thank you,
Stacy Chevrolet Customer Service


----------



## ts27330 (Jan 22, 2013)

I purchased my 2012 LT2 Cruze this past Wednesday. Parked in my attached (insulated} quiet garage. Heard the same weird noise (near the engine) the next morning before going to work. Could not locate the source. Car had been sitting overnight, unlocked. Next morning, no noise. Will try to pinpoint the souirce if it occurs again. I only noticed the noise when the hood was open. Noise was not constant. Sounded like a buzzing, solenoid connection type noise, ...short period of noise....stopped...then ...noise again... Had to go to work and could not fully investigate.


----------



## rmass09 (Apr 17, 2011)

I wouldn't be worried about it since so many people have heard it(heard it multiple times myself) and hadn't had an issue. Many theories behind it but no one has completely figured it out to my knowledge.


----------



## Chevy Customer Care (Oct 29, 2011)

ts27330, 
Keep us updated on what you find if the noise comes back! We're available to work with you and your dealership if you like. 
Sarah (Assisting Stacy), Chevrolet Customer Service


----------



## Aussie SRi-V (Aug 25, 2012)

Well after going through the 13 or so pages, I'll add in my conclusion after a little fault finding and research.
This sound has also plagued my Holden SRi-V 1.4T 6 Speed(Auto)
I have been able to set off the sound in the engine bay when accessing the door or boot (trunk). Don’t ask me why we call it a boot. Now off track.

Using the wife’s stethoscope(with permission), I was able to pin point the location of the high pitch noise.The sound emanates from my HYDRA-MATIC 6T40 (MH8) auto Transmission Control Module (TCM). The TCM and Electronic Hydraulic Control Module are located on the forward face of the transmission (Black plastic housing under the leading edge of the battery).

There are several solenoids contained within thishousing.


Shift pattern:
Variable Flow Solenoids
Shift quality:
Variable Flow Solenoids
Torque converter clutch: 
Variable Bleed Solenoid


For whatever reason the Body Control Module on its own, or Via the ECM is applying power to one or more of these solenoids. From what I have researched, it has to do with the fact that after you shut the vehicle off, there is still power to the transmission among many other modules in the vehicle. Transmission power application also occurs when I re-power the BCM. What you are hearing are the solenoids inside the TCM that are driven at a high frequency. When the modules "powerdown", usually a few seconds, the noise goes away.

I’m not a transmission expert so any one that can give me a better answer please feel free, I’m all ears. 

This is what I have discovered for the Auto in the Sri-V, I’m unsure how the transmission is set up for the manual 6 speed. 

I know its location, the technical reason why these solenoids are being powered when they are is still a mystery to me. 
My 2 cents worth.


----------



## Invierno (Nov 23, 2012)

Add me to this ongoing list of confused Cruze owners about this noise. For anyone who hasn't seen a video on it, here is mine. It just started doing it today:


----------



## Aussie SRi-V (Aug 25, 2012)

Invierno
I'd be interested to know if you placed a long common(blade) screw driver withthe blade tip on the TCM black housing and put your ear against the handle end,to see if you could actually pinpoint the noise to the TCM. 
If it is located within the TCM housing you will hear it very clearly throughthe handle of the screw driver.

Mark


----------



## Invierno (Nov 23, 2012)

Aussie SRi-V said:


> Invierno
> I'd be interested to know if you placed a long common(blade) screw driver withthe blade tip on the TCM black housing and put your ear against the handle end,to see if you could actually pinpoint the noise to the TCM.
> If it is located within the TCM housing you will hear it very clearly throughthe handle of the screw driver.
> 
> Mark


I'll try that tomorrow. Rain tonight...


----------



## K_lando5000 (Mar 26, 2013)

Just got my Cruze LT under a month ago and this sound is one of the first things I noticed about it. Always after I come home in the afternoon and park in the garage and the car is shut off. Once or twice I would get back in the car, put the key in the first position and then turn it off again and the sound went away. On other occasions, I would try unlocking and locking the doors to see if that affected anything and would notice that buzzing volume would fluctuate when I did. Very weird.

I'm not too concerned because it seems common and not really a 'problem'... but I'm also amazed that this thread is about a year old and still no one has really found a solid explanation for it...


----------



## jdubb11 (Mar 14, 2012)

mine only does it in very hot conditions after using the air conditioning. living in mpls, i may never hear the noise again lol. showed dealer the vid i made as well but told me to bring it in when its doing it. like im suppossed to know what its going to do everytime i shut the car off....


----------



## Action Hank (Jan 9, 2013)

jdubb11 said:


> mine only does it in very hot conditions after using the air conditioning. living in mpls, i may never hear the noise again lol. showed dealer the vid i made as well but told me to bring it in when its doing it. like im suppossed to know what its going to do everytime i shut the car off....


Same here, lots of heat + A/C = buzzing noise. It's happened to me a couple of times. Darn you Florida!!


----------



## jblackburn (Apr 14, 2012)

I think it's the AC expansion valve.

It happens on manual transmission cars after the AC has run. There's no solenoids or transmission computer.


----------



## caughron01 (Mar 25, 2013)

I have a 2013 1.4 Auto and have not heard this noise, although haven't really listened for it. I will listen now to see. Have any other 2013 Auto owners had this noise?


----------



## Robby (Mar 1, 2013)

I'm with jblackburn on this one......high side A/C pressure is in the 200psi range, low side in the 30psi range and the pressures will equalize after shutoff......takes about a minute or two.

They use a tiny diameter oriface instead of a expansion valve.....those disappeared from cars in the eighties......same concept though.

Rob


----------



## MD5335 (Oct 16, 2012)

Noticed the buzz today for the first time after 12k miles. Car is a stick, a/c was not on at all today, temps in the 60's. It lasted less than a minute but hard to ignore in my garage. For now, I will consider it a "feature" sort of like my steering "stiction" which has disappeared at least temporarily.


----------



## Deadstick (Mar 18, 2013)

Don't know why this would be confusing to anybody. The auxiliary water pump is mounted right up by the head to the left of the turbo, as you look at the engine. It is the black thing that the radiator hose is connected to. It runs for whatever amoount of time to keep the turbo from coking oil in the bearings. Not a big deal unless, later on down the line we find that it is a problem. I had one on a Dodge durango for aft heating that let loose. But lets face it: It was a dodge. (Really does not matter, I am sure it was a vendor supplied part, much like this one probably is)


----------



## obermd (Mar 3, 2012)

MD5335 said:


> Noticed the buzz today for the first time after 12k miles. Car is a stick, a/c was not on at all today, temps in the 60's. It lasted less than a minute but hard to ignore in my garage. For now, I will consider it a "feature" sort of like my steering "stiction" which has disappeared at least temporarily.


fftopic: So I'm not the only person who's noticed the steering "stiction" has lessoned over time. Mine's still there but not nearly as much.


----------



## CruznRpm13 (Apr 4, 2013)

Mine has made this noise two maybe three times. Twice I know for sure. I have a 2013 eco manual. Haven't really looked into it until I saw this thread. Now I feel like I have to know what it is. Haha


----------



## Invierno (Nov 23, 2012)

I've had the sound come back every now and then. After much research on this thread and others, I have concluded it's just a normal thing lol probably cycling coolant or oil to our turbo to cool it down. Who knows. It sounds weird, but a ton of us are experiencing it so it must be normal at this point lol


----------



## spacedout (Dec 7, 2010)

obermd said:


> fftopic: So I'm not the only person who's noticed the steering "stiction" has lessened over time. Mine's still there but not nearly as much.


I noticed the same thing as well. Mine was super bad(first time I noticed it) in Illinois on the beginning of a trip from Wisconsin to Texas and back. even after 3hours it was much more subtle. Never did it the rest of the trip. I have felt it from time to time a brief second but not the constant twitching I felt that day. Its been about 7,000miles since.


----------



## obermd (Mar 3, 2012)

I was looking through the owner's manual for my wife's Solara and it mentions a buzzing sound. I wonder if we have the same thing - fuel system evaporative leak test that's performed after the car is shut off.


----------



## jblackburn (Apr 14, 2012)

I've heard the Cruze make the evap system test before and it's from the middle/rear of the car. 

Want another weird noise? With the ignition on but engine not running, pump the brakes several times. You'll hear a vacuum pump for the brake booster run. 


Sent from AutoGuide.com App


----------



## chevycruze2012 (Nov 13, 2012)

Spiffster said:


> After a trip in the Cruze today I heard a buzzing sound coming from the Cruze, sounded like it was coming from under the hood so I lifted the hood and sure enough thats where it was coming from... could not tell where it was coming from exactly, just knew it was some component in or around the engine. Anybody else experience this?
> 
> Should probably mention I have the 1.4 turbo (ECO) and the noise died out after about a minute. Perhaps it was a fan but certainly didnt sound like one.


It is doing a self test for your ABS system. It wont do it all the time...however it should do it frequently.


----------



## jblackburn (Apr 14, 2012)

ABS test only happens when you start the engine and hit 12 mph the first time. It's a noticeable "clunk" from the front wheels. 


Sent from AutoGuide.com App


----------



## chevycruze2012 (Nov 13, 2012)

According to my dealership and a good friend of mine thats what they said it was...becaause i called about it like a month ago and noticed it from when i left the store. Im sticking to what they say since they are the certified mechanics.


----------



## jblackburn (Apr 14, 2012)

Ok. But we're talking about different noises. So it's not that. 


Sent from AutoGuide.com App


----------



## chevycruze2012 (Nov 13, 2012)

well the question i have is, is it a sound that is heard when you tap on the brakes? I want to make sure we are all thinking the same thing here


----------



## jblackburn (Apr 14, 2012)

No. You can hear that pump running after shutting the car off too and it's definitely a different noise than we are talking about here. 

Link to (that) noise: http://www.youtube.com/watch?v=pJZNwTpipuU


Sent from AutoGuide.com App


----------



## chevycruze2012 (Nov 13, 2012)

Oh okay. Yeah im not sure about that sound then. All I know is the one that goes off when you apply the brake, and it does that ABS check or whatever it was that my dealers told me. How does this sound sound exactly?


----------



## millscruze (May 21, 2013)

I ended up in this forum after seeking an answer for just this issue. I've had my 2013 Cruze LS 6 spd manual trans for not quite 3 months and I've noticed this buzzing noise twice. The first time I don't recall the outside temps being very hot and I'd been driving for less than 20 minutes. The second time was this past weekend and it was in the 80's outside and we'd been driving for maybe 45 minutes when we shut the engine off. I heard it and asked my husband to come listen - his thought was a fan of some type. At any rate, both times I put the key in the ignition and turned it forward (not fully to start the engine) and then back and the noise stopped.


----------



## dco (Sep 10, 2012)

I am having this same issue with my 2012 cruze 1.4T. I don't believe it has anything to do with the turbo since I heard the noise after just backing into the garage from my driveway. Car ran for less than a minute. I do however think it may have something to do with the a/c system since the defrost was on when I heard it. I can also hear the noise when the car is running. If you listen closely you can hear it with the car running and the hood down. Can't believe GM hasn't addressed this issue yet.


----------



## Robby (Mar 1, 2013)

^^^^^^^^
May not be an issue at all.......since most have heard it (me too) and it doesn't seem to cause any problem, I'm inclined to leave it at.....one of those things.
It would be nice if Chevrolet could give it a definition though......then I could say to myself ' Oh, it's just the 'X' doing its thing.
Kinda along the lines of the ABS self test or the power brake booster playing its little tune in the A.M.

I've wrenched for over 45 years.....over time, you stop fretting over these things.....as long as I can be satisfied there will be no problem down the road.

Rob


----------



## jdubb11 (Mar 14, 2012)

i wonder if flicking the key on and off to stop the sound is a good or bad thing.


----------



## obermd (Mar 3, 2012)

I really think it's something running that helps cool the car. My Montana did this and my wife's Toyota has a notice about this very issue in the owners manual.


----------



## HakeCruze (May 10, 2013)

The noise you are all hearing is the security system arming. You can test this by sitting in your car after you have parked and removed the key from the ignition. Once parked, open and close your driver's door while remaining in the car. Using the key fob, lock all doors. At this point if you open a door from the inside prior to the buzzing, the alarm will not sound. Open the door after the buzzing, the alarm will sound. Definitely nothing to do with the turbo as I have an LS and hear this sound all the time.


----------



## paulverisor (May 23, 2013)

I have heard this on my 2012 Cruze as well and like some of you I have cycled the key and it has gone away but not always. A time or two I've had to start it to make it go away. Either way, I would buy the theory of the A/C system to be the most likely. I would say the A/C system is equalizing after being shut off which is completely normal, but some component in these systems on these cars has an inherent noise when pressure is moving "backwards" so to speak as it equalizes, as it would when the system is shut down. The two components that come to mind that might make such a noise would be the expansion valve, as mentioned in other posts, and the compressor or variable displacement control valve on the compressor, as these compressors are of that variable displacement design and could make this noise anomaly as intermittent as everyone and myself have experience since it takes just the right conditions.


----------



## Gh0st (Oct 17, 2012)

Deadstick said:


> Don't know why this would be confusing to anybody. The auxiliary water pump is mounted right up by the head to the left of the turbo, as you look at the engine. It is the black thing that the radiator hose is connected to. It runs for whatever amoount of time to keep the turbo from coking oil in the bearings. Not a big deal unless, later on down the line we find that it is a problem. I had one on a Dodge durango for aft heating that let loose. But lets face it: It was a dodge. (Really does not matter, I am sure it was a vendor supplied part, much like this one probably is)


Pretty confident you are right on this. That's exactly where the noise was coming from the one time I heard it. Oddly, it was after my wife drove the car and I've never heard it do that when I drive it(every day).


----------



## Ltron (Dec 30, 2012)

I too have heard the noise on my 13 ECO MT. I have noticed that I can hear the noise with the engine running if the AC is on low. When the AC system starts you can hear the same buzzing as in the video. When you turn off the AC with the AC control, the noise goes away. On occasion the noise does not go away when the engine is shut off with the AC on.

To my ear as an EE, it sounds like a coil being pulsed at the frequency of the noise. I suspect that something in the AC system is being modulated by the AC controller and on occasion it does not shut down with the engine as you would expect.

It does seem to be comming from the area of the compressor but I have not isolated it to anything specific. 

I did notice that if I turn off the AC prior to shutting off the engine it goes away. It may or may not be an issue. I could think of scenerios either way. 

I have not tried the various possible combinations very much. It may well be that other interesting things are possible. I'll probably just try to turn off the AC before I stop the engine.


----------



## jdubb11 (Mar 14, 2012)

HakeCruze said:


> The noise you are all hearing is the security system arming. You can test this by sitting in your car after you have parked and removed the key from the ignition. Once parked, open and close your driver's door while remaining in the car. Using the key fob, lock all doors. At this point if you open a door from the inside prior to the buzzing, the alarm will not sound. Open the door after the buzzing, the alarm will sound. Definitely nothing to do with the turbo as I have an LS and hear this sound all the time.


so why has my security system only armed 4 times on hot days with my ac on?


----------



## jblackburn (Apr 14, 2012)

Ltron said:


> I too have heard the noise on my 13 ECO MT. I have noticed that I can hear the noise with the engine running if the AC is on low. When the AC system starts you can hear the same buzzing as in the video. When you turn off the AC with the AC control, the noise goes away. On occasion the noise does not go away when the engine is shut off with the AC on.
> 
> To my ear as an EE, it sounds like a coil being pulsed at the frequency of the noise. I suspect that something in the AC system is being modulated by the AC controller and on occasion it does not shut down with the engine as you would expect.
> 
> ...


Exactly. It's absolutely something in the AC system, and only happens when it has been running.

I'm thinking expansion valve - it's from the right area, but I could be wrong.


----------



## Ltron (Dec 30, 2012)

OK so I asked my Chevy dealer today what that buzzing noise is. They told me that it is the AC compressor. The AC compressor on this car is of the variable displacement type that is electrically controlled.

When the Evaporator gets too cold, the compressor displacement is reduced electronically. This is done instead of cycling the AC clutch. The car still has an AC clutch that is disengaged if the AC is off but it is not used for control.

I find it's most notable with the AC set to cold and the fan speed at minimum. If I increase the fan speed the noise goes away after a few seconds. The noise does fade in and out as you change the fan speed. I believe that the AC control is using PWM control like a FI to adjust the compressor displacement.

As for why the sound continues after turning the car off, they had no comment and I could not get it to do it. My car does do this on occasion but so far I have not figured out any sequence of events to cause it. I would not doubt that just about anything might cause it to stop if it did continue. This might include arming the anti theft system.

Basically they claim it's normal. Bring it back if it gets louder.

I guess I'll monitor the situation


----------



## JayZee (Jan 17, 2013)

My '13 LT 6spd manual has done this three times. First time I turned the car off with the A/C on. Did what others did and turned key to ON to check idiot lights, saw nothing, then turned the car OFF, and it stopped.

Second time it happened, I was at my hackerspace. Rushed in and grabbed a friend that was there who might be able to pinpoint the location. Couldn't, as the sound slowly faded away.

The third time it happened, I had driven about 45 minutes, but only had the air on about 20 minutes into the trip and turned it off about 10 minutes before arriving. (I only had the air on while driving on the expressway). When I arrived at my destination with the air turned off, the car made the noise. I did the key trick to turn it off. Not sure if that's bad or not.

To the person in post #68 (too lazy to find it and quote it), the reason why it doesn't stay on due to the key turning to position ON then OFF, I'm guessing based on my BS in computer engineering, is that the way they designed the system (if this is normal), is that the ECU looks for a value that is greater (or less than) another, and then turns this solenoid, motor, etc ON for X amount of time (perhaps based on the initial read value). When you turn your key ON then OFF (interrupting the current operation), the ECU reads again, but at this point, the data value it's checking is within the safe threshold, so the solenoid, motor, etc. does not kick back on or stay on. Just my two cents.
The way to prove me wrong is to be able to never get it to come back on after you go back ON to back OFF once you turn your car off, immediately after hearing the sound.

The turbo lube idea was pretty good. But since people with LS Cruzes are saying they hear it to (granted they're hearing the same issue), then it leads me to also believe it is the A/C unit. I have never heard it through the winter, even with defrost on. Only on hot days (I rarely use A/C).


----------



## Gh0st (Oct 17, 2012)

Ltron said:


> OK so I asked my Chevy dealer today what that buzzing noise is. They told me that it is the AC compressor. The AC compressor on this car is of the variable displacement type that is electrically controlled.
> 
> When the Evaporator gets too cold, the compressor displacement is reduced electronically. This is done instead of cycling the AC clutch. The car still has an AC clutch that is disengaged if the AC is off but it is not used for control.
> 
> ...


Yeah, I was definitely incorrect in my assumption. I never use the AC and the one day I did I heard the noise too.


----------



## Rauen (Apr 27, 2013)

If you have the 1.4 the sound is most likely, in English, the car cooling the turbo down. It has an internal system that keeps it from overheating and it makes a high pitched buzz.


----------



## Chevy Customer Care (Oct 29, 2011)

Hello all, 

I am sorry to hear you guys are experiencing this concern. You can always private message us your name, VIN, mileage, phone number, and address, so we can look further into your concerns. Look forward to hearing from you.

Erica Tiffany
Chevrolet Customer Service


----------



## CruzeTech (Mar 23, 2012)

It's not even a concern. From what we've seen in this thread alone, it happens to every Cruze, so there isn't really anything to look into. Nothing is wrong with the car, it's some sort of pump that runs after the car turns off. I've even heard mine with the car running.


----------



## ChevyMgr (Oct 27, 2010)

The fix for the buzz after turning the vehicle off will be a re-program and it will be out soon. I will post when it comes out and give the PI or bulletin number so you can give to your dealer.


----------



## AVCruze12 (Feb 27, 2013)

dacruze said:


> Gfxdave99, you're correct, but in this case, i'm not so sure that he was wrong. I've heard mine do it too, and it definately doesn't sound like the fan!!! what i'm hearing sounds like a hgher pitch noise than the hummm of the fan. but what is it????? - Dan


Video of my cruze doing this, seems like the thermostat to me Cruze noise - YouTube



Sent from my iPhone


----------



## ChevyMgr (Oct 27, 2010)

AVCruze12 said:


> Video of my cruze doing this, seems like the thermostat to me Cruze noise - YouTube
> 
> 
> 
> Sent from my iPhone


It is the A/C compressor. Only happens under the right conditions at engine shut off. Stay tuned.


----------



## jdubb11 (Mar 14, 2012)

ChevyMgr said:


> It is the A/C compressor. Only happens under the right conditions at engine shut off. Stay tuned.


do we know what exactly what with the a/c we are hearing or what the perfect conditions are. mine has only done it about 4 times and the one time i made an appointment of course it didnt make the noise. thanks for your help on this matter!!


----------



## dco (Sep 10, 2012)

It does not only happen at engine shut off. I have heard mine while the engine was idling.


----------



## ChevyMgr (Oct 27, 2010)

jdubb11 said:


> do we know what exactly what with the a/c we are hearing or what the perfect conditions are. mine has only done it about 4 times and the one time i made an appointment of course it didnt make the noise. thanks for your help on this matter!!


I was told that if the blower is turned off and the key is turned off within 10 seconds and the pulse width of the solenoid inside of the a/c compressor is between 45-58%, it can cause a buzz like a reed for 10 seconds to 10 minutes. Ponder that one. :wacko:


----------



## rscruze (Apr 11, 2012)

jblackburn said:


> No. You can hear that pump running after shutting the car off too and it's definitely a different noise than we are talking about here.
> 
> Link to (that) noise: http://www.youtube.com/watch?v=pJZNwTpipuU


Hi all,

Since yesterday morning my 2013 ECO 6MT with 4500miles has been making a buzzing noise as well. I knew I had read something about this on the forum here and so checked it out this morning. 

For background, I have never heard any buzzing noises before. I only started hearing this since yesterday. It is certainly not the same as the metallic buzz most people report on here and seen in the videos. However, mine matches exactly what jblackburn shows in the video in this post. 

I hear it first thing in the morning (cool car in the garage) when I turn the key to ACC. I popped the hood and I could hear it from somewhere near the passenger side engine bay (near the turbo). I don't hear it after turning on the car (possibly because engine is louder). I do hear it though after a drive and switching the car off. I need to go and check again now after the car has cooled down from the drive. 

jblackburn or anybody else have any idea about this particular sound that you show in this video? 

I am concerned as I have only just started hearing this sound. 

Thanks.


----------



## jblackburn (Apr 14, 2012)

That noise is a booster pump that builds up vacuum pressure for the brake booster assist when the engine is off or not providing enough vacuum (e.g. turbo under boost or at idle on a cold morning when the valve overlap allows for very little vacuum).

It's normal for me to hear it when coasting to a stop in a parking lot with the engine idling, or putting my foot on the brake sometimes before starting the engine. 

If you hear it pretty often, perhaps you have a bad check valve near the brake booster leaking vacuum pressure and/or a vacuum leak in a hose somewhere. If you ever experience problems with braking in the morning with a cold engine or in reverse, take your car in immediately. Otherwise, I wouldn't worry about hearing the noise too much.


----------



## rscruze (Apr 11, 2012)

jblackburn said:


> That noise is a booster pump that builds up vacuum pressure for the brake booster assist when the engine is off
> ...
> 
> If you hear it pretty often, perhaps you have a bad check valve near the brake booster leaking vacuum pressure and/or a vacuum leak in a hose somewhere. If you ever experience problems with braking in the morning with a cold engine or in reverse, take your car in immediately. Otherwise, I wouldn't worry about hearing the noise too much.


Awesome! Thanks for the quick reply jblackburn. Now I am a bit concerned after reading your reply. Mainly because I didn't use to hear it before. I can understand the booster assist providing more vacuum, but if it keeps on doing that till I start the car, I don't think that is expected. I need to check the brake test as you mentioned. The last couple weeks has been in mid three digits here (105 to 112F) but since yesterday we got some heavy rains and temp dropped to high 79F. I wonder if that would affect this any. 

I will do some more data collection on this from today and report back. I sure hope nothing is wrong with my brake system. Gulp! I have wife and two little kiddos with me most long drives everyday.

Thanks again jblackburn!


----------



## jblackburn (Apr 14, 2012)

> I can understand the booster assist providing more vacuum, but if it keeps on doing that till I start the car, I don't think that is expected.


It normally runs for 3-5 seconds and then cuts off. If you hear it running for 10-15 when you just flip the key on, something isn't holding vacuum pressure. Temperature has no effect.


----------



## rscruze (Apr 11, 2012)

jblackburn said:


> It normally runs for 3-5 seconds and then cuts off. If you hear it running for 10-15 when you just flip the key on, something isn't holding vacuum pressure. Temperature has no effect.


Got it! I surely am hearing it much longer since I got out of the car went and opened the hood and looked under. Still heard the sound. Came back and sat in my to start it and at that point I could still hear it till starting the car. 

I will be talking to my dealership shortly, but I am afraid they will not hear the sound and send me off with the "everything's normal" :- (
I'll let you know what I find out and what happens. 

Thanks.


----------



## rscruze (Apr 11, 2012)

I checked out my car over lunch and definitely the sound stays on for a long time--i.e. till I started the car. Also I noticed that it is different from the brake vacuum sound in jblackburn's video. Mine seems more of a fast whirring noise. 

I tested out the brakes and they seem fine. 

I took a video of the sound from my car. Hope you all can see it and somebody can figure out what it is. Note that this is with the ignition key in ACC and engine not running. As you can see in the video the radiator fan is also not turning, so the sound is something else.


----------



## jblackburn (Apr 14, 2012)

Please make your video viewable to us sir (it's currently listed as private).


----------



## rscruze (Apr 11, 2012)

jblackburn said:


> Please make your video viewable to us sir (it's currently listed as private).


oops! sorry! Fixed! Can you please take a look again.


----------



## jblackburn (Apr 14, 2012)

That sounds like it is coming from somewhere around the AC compressor area (it's to the left of the turbo there).

My car pretty much sits at home, so I won't be able to try this theory out until later. Go inside the car and turn off the AC button and turn the fan speed off as well. See if it still makes the noise. Yours may be a slightly different noise of what GMTech was describing a few pages back in the thread.

I don't know where that vacuum pump is running under the hood, but I would guess it's somewhere near the back or left side of the engine bay and NOT in that area. Your noise sounds different anyway.


----------



## rscruze (Apr 11, 2012)

jblackburn, while this sound is going on, the AC is switched off and the fan is OFF as well. Interestingly the radio is also OFF. The ignition is in ACC and so the dash is lit up and so are the perimeter lights.


----------



## Chevy Customer Care (Oct 29, 2011)

Hi rscruze

Please let me know when you decide to take your Cruze to the dealer. I can set up a service request for you and assist you in getting the issue diagnosed and repaired. 

Jackie
Chevrolet Customer Care


----------



## rscruze (Apr 11, 2012)

Chevy Customer Service said:


> Hi rscruze
> 
> Please let me know when you decide to take your Cruze to the dealer. I can set up a service request for you and assist you in getting the issue diagnosed and repaired.
> 
> ...


Hi Jackie,
Thank you for your offer to help out. Unfortunately I did not see your post until today. Sorry about that. Also strange thing is that this morning I did not hear the sound. I will be listening carefully the next few days and report back if I hear it again. 

That is too bad though, since I am most worried about issues like this that come out of nowhere, nobody has an answer and then disappear just like that without doing anything 

Thanks.


----------



## Chevy Customer Care (Oct 29, 2011)

Hi rscruze

In the future please don't hesitate to contact me if you need any assistance. You can send me an inbox message. Please keep me posted.

Jackie
Chevrolet Customer Care


----------



## rscruze (Apr 11, 2012)

Chevy Customer Service said:


> Hi rscruze
> 
> In the future please don't hesitate to contact me if you need any assistance. You can send me an inbox message. Please keep me posted.
> 
> ...


Will do Jackie. 

Thank you.


----------



## Woodyw (Jul 22, 2013)

AVCruze12 said:


> Video of my cruze doing this, seems like the thermostat to me Cruze noise - YouTube
> 
> 
> 
> Sent from my iPhone


I have attempted to chase down the source of this same sound several times from my '13 2LT 1.4L w/manual trans. To me it sounds like a pressure equalization since it fades out as opposed to an abrupt end such as if it were an electric device turning off. My theory was turbo related until reading the 20 pages of mostly similar comments including the non-turbo LS 1.8L owners w/similar complaints. That leads me to suspect A/C pressure as mentioned by others previously. In response to those who said that the noise stops with a key on/off (i haven't tested)...perhaps there is a compression bypass that activates on key-on to facilitate starting and releases any pressure. Just guessing on that.

I believe this is still unresolved since I haven't seen resolution or acknowledgement of issue from GM. Pls let me know otherwise.


----------



## obermd (Mar 3, 2012)

I have it and don't worry about it. My Pontiac Montana and Transport had it. The owner's manual for the Montana actually stated that you would hear the engine fans running after shutdown. It is part of the car's built in cool down process and is the result of various pumps and fans running to properly cool the engine. Other than curiosity about exactly what is generating this noise, this really isn't an issue.

Also, when I had the mold and mildew cleaned out of my A/C, the HVAC after-blow was turned on. After-blow is loud and can be heard from several yards away.


----------



## phugoff (Oct 4, 2013)

Has anyone been able to nail the cause of this down? I have a '13 cruze LS manual and i hear the same noise.


----------



## Chevy Customer Care (Oct 29, 2011)

Hi phugoff

Have you been to the dealership yet? Your Cruze should sill be under warranty. If the sound concerns you I would suggest you bring this to the attention of your Service Adviser. If you want my assistance with this at all just send me a private message.

Jackie
Chevrolet Customer Care


----------



## Bonaventure (Dec 28, 2012)

Hey guys,

I hate to add to an already drawn out thread but I had this happen to me as well today. I had just done a short trip to pick up pizza for the work buddies and after I got out I heard it. When I pressed the lock button on my key fob the noise got quieter and then went back to the same noise as the videos that have been posted which says to me that this is electrical and probably not some pressure bleed off. 

I did not use the AC today, and haven't in weeks since it has been cold out so I doubt it was the AC compressor. I was a little harder on the car with the suburban Redmond driving around microsoft. Electric related/hard driving in 60 degree temps with no AC? Maybe it is that turbo cooler motor? Sure is a loud little thing!

Figured this would help us all zero in on that square wave sounding issue.


----------



## obermd (Mar 3, 2012)

It's not the A/C system. This sound is nothing more than the various pumps in the engine running coolant around to help cool down the engine at a consistent rate.


----------



## brian v (Dec 25, 2011)

FAQ this one .....................................................


----------



## DELCO666 (Nov 9, 2013)

Could you be hearing the brake booster vacuum pump? Ignition on/engine off pump the brakes a couple times and the vacuum pump will cycle. New recall on the micro switch that controls the pump. Can cause an intermittent hard pedal


Sent from AutoGuide.com Free App


----------



## Merc6 (Jun 8, 2013)

DELCO666 said:


> Could you be hearing the brake booster vacuum pump? Ignition on/engine off pump the brakes a couple times and the vacuum pump will cycle. New recall on the micro switch that controls the pump. Can cause an intermittent hard pedal
> 
> 
> Sent from AutoGuide.com Free App


 Recall is on auto trans and us manuals have this as sound as well. 31*F is too cold for a/c compressor to kick on so it's not that either. It's cooling


----------



## minsik (Oct 24, 2013)

that sounds like my new my14 jh sri-v car turbo 1.6L.

I believe if its the turbo its the cooling making sure the turbo does not overheat and damage. It may go on and off over a while until the whole intercooler and turbo have cooled down. its a little pump circulating coolant. 

remember the timers that trucks/cars had to run the engine and cool down before the engine could be stopped to stop overheating. I rechon its the same thing, just quieter. 

MInsik


----------



## mc2crazy (Oct 25, 2013)

My 1LT did not make this buzzing noise.
My new 2014 diesel Cruze clearly makes this buzzing.
The car was sitting in the garage cooled off and we were opening the doors and trunk when we noticed it. It seems to me to be something in the alarm system... seems to be coming from an electrical box on top of the battery.

OK, I can duplicate it by opening a door, closing the hood or anything tied into the electrical system. It runs for 20-40 seconds depending on what trips it. It shuts off with a "click." 
Using an old mechanic's trick I used a stick placed up to my ear touching the other end to various parts under the hood. There's a black box on top of the battery with electrical stuff in it. I'm not an electrical engineer and don't know what all of those things are in that box. I'm guessing it's the retained power or the alarm system. It also may be something else that's in contact with the battery.

Hmmmmmmmmmmmmmmmmmmmmmmmmmmmmm..... 20-40 seconds or so... "click"... then it's off.

Someone with a service manual might be able to see what's in this box that might be causing it... or something transferring the sound to this box.


----------



## Johnny M. (Feb 24, 2012)

mc2crazy said:


> My 1LT did not make this buzzing noise.
> My new 2014 diesel Cruze clearly makes this buzzing.
> The car was sitting in the garage cooled off and we were opening the doors and trunk when we noticed it. It seems to me to be something in the alarm system... seems to be coming from an electrical box on top of the battery.
> 
> ...


It is the vacuum pump for the PB booster if you have an auto trans.

Sent from my S3


----------



## Merc6 (Jun 8, 2013)

Johnny M. said:


> It is the vacuum pump for the PB booster if you have an auto trans.
> 
> Sent from my S3


Maybe this is a different sound then. Since my last post I had the sound come back then started the car up and it never left. I had just overtaken a car aggressively before parking it a minute later.


----------



## jblackburn (Apr 14, 2012)

Johnny M. said:


> It is the vacuum pump for the PB booster if you have an auto trans.
> 
> Sent from my S3


Nope, different sound than what everyone's describing and it runs for 5-10 seconds at most.


----------



## Johnny M. (Feb 24, 2012)

jblackburn said:


> Nope, different sound than what everyone's describing and it runs for 5-10 seconds at most.


Maybe I'll have to start unplugging relays/fuses until it quits....

Sent from my S3


----------



## DELCO666 (Nov 9, 2013)

Just because it makes a noise dosent make it broken. If you start unplugging unknown components your just going to screw things up. How is a technician supposed to diagnose a car that has owner induced dtc,s set in it. Drive it and enjoy. If it truly is broken you will get a warning lamp and it will be easy to diagnose and repair. 


Sent from AutoGuide.com Free App


----------



## topchop (Sep 3, 2014)

Hoping that this thread is still alive and monitored, have a question on the "buzzing" sound (see vid in post #174).
Exactly the same sound that I have in my 2012 LS 1.8L 6 speed manual. Service Department Advisor could not hear, therefor not having any idea. "Bring it back and leave it for a few days".
Question: Since so many people have it, wether they know it's a problem or not, will it do any damage ignoring it?


----------



## Ger8mm (Mar 13, 2014)

I know the problem, you officially have the only cruze in the world with air suspension. So congratulations because we are all jealous of you lol:eusa_clap:


----------



## jdubb11 (Mar 14, 2012)

Im not sure if this has already been said but you can turn your key on and off and the sound will stop. Definitely something with the air conditioning. U can here this sound with car running and air conditioning on. Sometimes when you shut the car off the sound will remain on. Turning the key to the on position and back to off will make the sound stop


----------



## Chevy Customer Care (Oct 29, 2011)

Hi topchop,

I'm sorry to hear of the buzzing noise that your experience in your Cruze and I can only imagine how frustrating this might be. I understand that you have taken your vehicle to your dealership and they were unable to duplicate the noise. I am unable to provide technical advice, but if any extra assistance is needed with your concern we can certainly contact your dealership on your behalf and discuss this further. Please private message us your VIN, mileage and contact information if we can look further into this matter for you. 

Kristen A.
Chevrolet Customer Care


----------



## GeoHawk (Jan 24, 2014)

There is a GM service document for this: *#PI1267: High Pitched Whine or Buzz Noise from Engine Compartment After Engine is Turned Off - (Jul 8, 2014)

*The fix is a software update for the HVAC module to correct this issue. I had it done to mine a couple of months ago. Never saw this thread before now.


----------



## gyrfalcon (Dec 27, 2013)

GeoHawk said:


> There is a GM service document for this: *#PI1267: High Pitched Whine or Buzz Noise from Engine Compartment After Engine is Turned Off - (Jul 8, 2014)
> 
> *The fix is a software update for the HVAC module to correct this issue. I had it done to mine a couple of months ago. Never saw this thread before now.


Does it sound like this? I only was able to tape a few seconds of it.


----------



## GeoHawk (Jan 24, 2014)

gyrfalcon said:


> Does it sound like this? I only was able to tape a few seconds of it.


Yes, it sounded exactly like that.


----------



## Koybuc (Aug 28, 2015)

How much would it cost to get a software update without any warranty?


----------



## 2015cruzer (Dec 13, 2015)

Hey guys, I work as a mechanic for GM and possibly have a solution for this. I found a PI on my service info page which helps techs out for fixing cars. Does this describe your condition?????

"Some customers may comment on a buzz type noise after the vehicle has been shut off. The noise may be noticed with the A/C on and may last up to 10 minutes after the vehicle is shut off and most often is intermittent. The noise is similar to the sound of a reed valve emitting a fairly constant tone.

The air conditioning refrigerant solenoid valve is not consistently powered down at key off due to variation in drive cycle and emissions monitoring. When the solenoid is operating at a 50 to 60 PWM range and certain conditions are met at key off, it will continue to emit this buzz type noise until the system powers it down."


If so, go to your dealer and see if you can get the HVAC control module updated with the latest software.


----------



## stowbilly (Apr 24, 2013)

Koybuc said:


> How much would it cost to get a software update without any warranty?


I would like to know this, too. I`ve had my Cruze in multiple times over the last 3 years on this issue and have never gotten a fix.
My Cruze has this buzzing sound at different times regardless of weather, AC on or off, and when the car is running or just shut off.
Now, the warranty is up.


----------



## GuliblGuy (Dec 6, 2017)

Just got a 2012 1.4 Cruze...heard this issue happening on mine too


----------



## Lazer (Feb 14, 2016)

Deadstick said:


> Don't know why this would be confusing to anybody. *The auxiliary water pump *is mounted right up by the head to the left of the turbo, as you look at the engine. It is the black thing that the radiator hose is connected to. It runs for whatever amoount of time to keep the turbo from coking oil in the bearings. Not a big deal unless, later on down the line we find that it is a problem. I had one on a Dodge durango for aft heating that let loose. But lets face it: It was a dodge. (Really does not matter, I am sure it was a vendor supplied part, much like this one probably is)


There is no extra water pump.


----------



## JoBivins30 (Jan 12, 2020)

My 2012 Chevy Cruze LT is making this noise, but I have never heard it before until after we had the turbocharger replaced. I hope this normal. It kept making the noise even after we took the battery cables off.


----------



## radio_davio (Dec 28, 2018)

I had this after having the engine replaced. I found a Chevy service bulletin saying it was the HVAC relay being in an unknown state when the engine is shut off. The bulletin required having the computer being reprogrammed. One dealer wanted a full service hour to do this, and another was willing to do it for 1/2 service hour. Obviously I got it done for 1/2 hour!

It fixed the buzzing - AND - my outside temp. display is accurate, which it never has been before - AND - the car can retrieve my phone's contact list, which it never has been able to do.


----------

