# Noise at 15 mph



## Craigels (Jan 7, 2012)

I have noticed on BOTH cars (so I assume it's normal) at 15 mph, after initial startup and takeoff, a weird noise that can be heard inside the car. You can feel it in the accelerator pedal as well. It sounds like what you hear from an ABS module on a hard stop, like a purging sound. It's under acceleration only. Just curious as to what it is. Thanks


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## bubby2411 (Sep 3, 2011)

I have always noticed it but for me it only does it during cold start ups I have just ignored it and not let it bother me


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## sciphi (Aug 26, 2011)

It's the ABS/stability control doing its self-check. Mine does it too. It's normal.


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## ShawnsCruze (Jan 18, 2012)

mine does it also on cold starts, and only when the car is shifting into second. little strange but havent done anything about it yet


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## Craigels (Jan 7, 2012)

I figured it was normal since both our cars did it. Not worried, just curious! Thanks!


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## Mick (Dec 31, 2011)

Good I was just going to post about this cause it is a bit annoying. Shouldn't be "normal" though, or this would be apopular subject.


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## Smurfenstein (Nov 16, 2011)

What does the sound ... sound like?


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## josheco12 (Feb 5, 2012)

Sounds halfway between the doors locking loudly and a clunk.
Mine does this also.


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## rbtec (Feb 3, 2012)

ShawnsCruze said:


> mine does it also on cold starts, and only when the car is shifting into second. little strange but havent done anything about it yet


Mine does this exact same thing also. Thought I was imagining it, guess not. Must be normal.


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## 7STW (Mar 30, 2011)

Yes, it "seems" to happen on the 1/2 shift and is most noticeable under slow acceleration, like gliding along in a parking lot.Right about 13 to 14 mph on my buggy.I'd describe it as between a clunk and a clank.


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## Mick (Dec 31, 2011)

I'd say a combination of: sounds like doors locking (if the lock was in the engine compartment) and something scrapping because the vibration in the pedal was more noticeable with the music where I keep it. 

If it's the abs, does that mean ours are faulty?


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## Chevy Customer Care (Oct 29, 2011)

Craigels said:


> I have noticed on BOTH cars (so I assume it's normal) at 15 mph, after initial startup and takeoff, a weird noise that can be heard inside the car. You can feel it in the accelerator pedal as well. It sounds like what you hear from an ABS module on a hard stop, like a purging sound. It's under acceleration only. Just curious as to what it is. Thanks



Craigels,
When the engine is started and the vehicle begins to drive away, ABS checks itself. A momentary motor or clicking noise might be heard while this test is going on, and it might even be noticed that the brake pedal moves a little. This is normal. If you feel that this is not the issue I would suggest that you contact your local dealership and have the service center look at your vehicle for you. If you have any further questions please feel free to message me.
Thank you,
Stacy Chevrolet Customer Service


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## NickD (Dec 10, 2011)

ABS check has been a GM trademark for years, switching on the ignition switch does a static check. My 2012 2LT had a manual transmission, but just hear a quick buzz at about 6-8 mph for the dynamic check. About that same speed, the auto door locks engage. Ha, tell my wife, getting old now, we are safe. So those are two noises that are normal, but the ABS check only happens once when you first start off and keep the engine running. Have to hit the manual door locks to drop off a passenger, but when I take off again, the doors lock again.

Now if getting a third noise with an automatic transmission, I only test drove one. Was in late November, car was outside and cold, but recall it was smooth. Dealer tried to talk my wife and I into buying it, but we both wanted a stick. From all the slippage and other AT problems reported here, wondering if they topped these things off with fluid. Has to be up on level rack, and the top side filler plug has to be removed with fluid dripping down to be full.


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## elegant (Jan 6, 2011)

Could it be the automatic door-locking system?


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## Craigels (Jan 7, 2012)

Thanks for all the replies! Seems like we're all on the same page.

Thanks Stacy, Chevy Customer Service, for the "official" word. I figured it was nothing to worry about.


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## rwgoet (Feb 20, 2012)

I have a 2012 Cruze LT1 manual and I hear the same clunk/clank on cold starts. It is usually when in 2nd gear but have heard it when staying longer than usualin 1st. I thought it might be something with the turbo, but it also sound slike a flap closing(?) Based on the comments in this thread I'll consider the ABS as a cause. I'll also shut the car off as soon as it happens, restart and see if I hear it again. 

My car has 3000 miles and I've heard the sound since I first got it (wish I noticed it on th etest drive). I plan to take to the dealer in the next coupl eof weeks. Overall I'm happy with the car as I'm averaging 38 mpg, mostly highway and I'm driving very conservatively making a game out of stretching out mpg.

Good luck to all dealing with this noise


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## Chevy Customer Care (Oct 29, 2011)

rwgoet said:


> I have a 2012 Cruze LT1 manual and I hear the same clunk/clank on cold starts. It is usually when in 2nd gear but have heard it when staying longer than usualin 1st. I thought it might be something with the turbo, but it also sound slike a flap closing(?) Based on the comments in this thread I'll consider the ABS as a cause. I'll also shut the car off as soon as it happens, restart and see if I hear it again.
> 
> My car has 3000 miles and I've heard the sound since I first got it (wish I noticed it on th etest drive). I plan to take to the dealer in the next coupl eof weeks. Overall I'm happy with the car as I'm averaging 38 mpg, mostly highway and I'm driving very conservatively making a game out of stretching out mpg.
> 
> Good luck to all dealing with this noise




rwgoet,
I would suggest that you take your vehicle into the dealership if you feel that you are experiencing something other than the ABS self check. Your dealership is in the best position to diagnose your vehicle for you. Please keep me posted on the outcome of your visit to the dealership. If you have any further questions please feel free to message me.
Thank you,
Stacy Chevrolet Customer Service


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## SkullCruzeRS (Nov 3, 2011)

Have the same noise at about 12mph only when first starting up glad to know it's just the ABS.


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## obermd (Mar 3, 2012)

As others have stated, this is the ABS and all GM cars with ABS do it. What's actually occurring is the ABS system is actually pulsing the brakes without engaging them, which is why you can feel this in the brake pedal. This is the only way to verify the ABS system will actually be able to pulse your brakes when it needs to do so. It's documented to occur at 20 KPH (12.6 MPH), which is unfortunately right at where most of us with sticks shift from 1st to 2nd. You can verify it's not the shift simply by staying in 1st longer or shifting to 2nd much earlier.


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## AkotaHsky (Feb 11, 2012)

Glad I had time to check the forums. I was about to have to run up in the dealer very unhappy.

I get this at 2600RPMs normally in 1st gear (I been testin everyday), or I guess around that same 10-15MPH mark. Its a click/clunk. Almost sounds like something gets stuck and releases. You feel it in the gas pedal, break pedal, and sometimes the clutch. The light also dim for a split second.


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## AkotaHsky (Feb 11, 2012)

AkotaHsky said:


> Glad I had time to check the forums. I was about to have to run up in the dealer very unhappy.
> 
> I get this at 2600RPMs normally in 1st gear (I been testin everyday), or I guess around that same 10-15MPH mark. Its a click/clunk. Almost sounds like something gets stuck and releases. You feel it in the gas pedal, break pedal, and sometimes the clutch. The light also dim for a split second.



Granted - Why am I just now noticing this almost a year into the car......... Hrm......


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## obermd (Mar 3, 2012)

Your lights shouldn't dim during the ABS pulse testing. This indicates to me either your battery is weak or your alternator isn't working properly.


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## AkotaHsky (Feb 11, 2012)

obermd said:


> Your lights shouldn't dim during the ABS pulse testing. This indicates to me either your battery is weak or your alternator isn't working properly.


\

I noticed this the last time I drive. It also could have just been me sleeking out of my community trying not to graze my bumper on the ground and a bad shift. 


Still, never noticed it till a few weeks ago.


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