# Cylinder #1 misfire, no loss of power.



## EricSmit (Dec 21, 2016)

Alright guys, I developed a misfire almost home from Lordstown. It only registers the misfire at idle, but below 2k RPMs in 4-6th gear it'll miss as well. 

It pulls WOT perfectly fine, and just as powerful as normal. 

No drivability problems besides the below 2k miss in 4-6th gear and at idle. 

It's only cylinder 1. Attached is a picture of the plug I pulled out of cylinder one. 

I swapped cylinder 1-2 plugs and the coils from 1 and 4. The misfire remained on cylinder 1. 

My mechanic friend has only seen it once before, years and years ago, but it was an injector issue. 

Anybody else want to brainstorm?


----------



## JRB'sOilburningCruze (Feb 25, 2015)

If you confirmed spark, it either has to be fuel or air. Easy thing to do first is put a compression gauge on it to rule out a burnt valve other mechanical issue. Once that is done go from there.


----------



## EricSmit (Dec 21, 2016)

JRB'sOilburningCruze said:


> If you confirmed spark, it either has to be fuel or air. Easy thing to do first is put a compression gauge on it to rule out a burnt valve other mechanical issue. Once that is done go from there.


Question; if it was a burnt valve or something, wouldn't I have an issue with a WOT pull from 0 mph in first to 80 in third?


----------



## obermd (Mar 3, 2012)

Take a look at the spring coil. We've seen corrosion on the coils in the past. Corrosion will cause the car to misfire at low RPM while allowing the more frequent electrical charges at higher RPM to get through to the plug.


----------



## EricSmit (Dec 21, 2016)

obermd said:


> Take a look at the spring coil. We've seen corrosion on the coils in the past. Corrosion will cause the car to misfire at low RPM while allowing the more frequent electrical charges at higher RPM to get through to the plug.


You're talking about the spring inside the boot?


----------



## Robby (Mar 1, 2013)

I'm not familiar with the new 1.4.......is it Direct Injection?
If it is, this most likely will be a injector issue......I'm thinking high resistance but a possibility of the injector being slightly obstructed at the pintle.

When at higher engine speeds (and load) the injector opens further, possibly (in this case) enough to overcome the lean condition (misfire).

Best wag I can come up with from a keyboard.

Rob


----------



## EricSmit (Dec 21, 2016)

Robby said:


> I'm not familiar with the new 1.4.......is it Direct Injection?
> If it is, this most likely will be a injector issue......I'm thinking high resistance but a possibility of the injector being slightly obstructed at the pintle.
> 
> When at higher engine speeds (and load) the injector opens further, possibly (in this case) enough to overcome the lean condition (misfire).
> ...


It is direct injected.


----------



## IndyDiesel (May 24, 2015)

It's under warranty and you work at a Chevy dealer, why not let them fix it rather than guessing what the problem is?


----------



## jblackburn (Apr 14, 2012)

Beyond the coil itself being bad, I can think of two possibilities - one that they're known for:

1) Valve isn't closing completely due to carbon build-up. Compression won't be zero, but it will be slightly low. Shouldn't yet be an issue with an engine with so few miles on it, and that would be terrible news for other LE2 owners.
2) Cracked piston. Two have had it happen on LE2's already on cyl #1 (and it happens all the time with LUJ/LUV engines), but I think they both ran 87 oct. And then there's the issues with the 1.5 which is almost mechanically identical to the 1.4.

I think my first diagnostic tool would be a simple compression test. If that checks out ok and is within the range of all of the other cylinders, then you could begin by switching coil packs between cylinders to see if that makes a difference, or looking into an injector issue, which would be a new one to me.


----------



## EricSmit (Dec 21, 2016)

jblackburn said:


> Beyond the coil itself being bad, I can think of two possibilities - one that they're known for:
> 
> 1) Valve isn't closing completely due to carbon build-up. Compression won't be zero, but it will be slightly low. Shouldn't yet be an issue with an engine with so few miles on it, and that would be terrible news for other LE2 owners.
> 2) Cracked piston. Two have had it happen on LE2's already on cyl #1 (and it happens all the time with LUJ/LUV engines), but I think they both ran 87 oct. And then there's the issues with the 1.5 which is almost mechanically identical to the 1.4.
> ...


I already swapped coils, misfire stayed on cylinder one. 

Misfire doesn't happen on a WOT pull. It pulls hard like normal all the way to redline. 

It's certainly a confusing one for me.


----------



## MyLonewolf25 (Dec 23, 2016)

My best guess is fuel at this point or something weird with ignition 

Bad ground that fixes itself at wot because it just powers through or it jimmies itself into a better position? Long shot but maybe 

I'd pretty much say fuel at this point try moving injectors around?


Sent from my iPhone using Tapatalk


----------



## EricSmit (Dec 21, 2016)

MyLonewolf25 said:


> My best guess is fuel at this point or something weird with ignition
> 
> Bad ground that fixes itself at wot because it just powers through or it jimmies itself into a better position? Long shot but maybe
> 
> ...


The problem with moving injectors that day was that I didn't want to risk pulling an injector and not having a crush washer to replace.


----------



## cvasquez636 (Mar 19, 2017)

Best bet is injector issue, I doubt it would be a ground issue because then the misfire would be sporadic throughout the rpm band.


Sent from my iPhone using Tapatalk


----------



## EricSmit (Dec 21, 2016)

I've had a couple people suggest cracked piston. I have it scheduled to go in to service on Thursday, because that's the first day a loaner vehicle will be available to me. I did mention my concerns and my issues, so either it'll be fine until Thursday and then be fine, or it'll explode and I'll not worry because they told me I could wait until Thursday.


----------



## JRB'sOilburningCruze (Feb 25, 2015)

I'm starting to sound like a cranky old man, eliminate the easy stuff first. Before messing with injectors, coil packs etc or guessing about other parts, pull a compression test. It is an easy diagnostic to complete. I will take less than an hour to complete. Once you know things are mechanically sound start going after fuel injectors, coil packs, or other electrical gremlins. If you have lower compression on #1, that will be the root of your misfire. 

My sons S10 with a 4.3 kept throwing a P300. A new distributor cured the P30, but promptly got a P304. The distributor drive gear was worn and would wobble on the cam gear causing a P300. But I kept getting the P304. New plugs, wires, fuel injector spider, etc. Kept getting P304. Drove me nuts. Would only come on when the A/C got turned on. If AC was off and drove very gently, no code. Finally after listening to other people, pulled a compression test and sure enough #4 was low. Burnt valve. Root cause was leaky intake manifold gaskets caused a lean condition. I had the heads rebuilt and it runs smooth as silk with 245K miles.


----------



## sparkman (Oct 15, 2015)

Are you tuned?


----------



## EricSmit (Dec 21, 2016)

JRB'sOilburningCruze said:


> I'm starting to sound like a cranky old man, eliminate the easy stuff first. Before messing with injectors, coil packs etc or guessing about other parts, pull a compression test. It is an easy diagnostic to complete. I will take less than an hour to complete. Once you know things are mechanically sound start going after fuel injectors, coil packs, or other electrical gremlins. If you have lower compression on #1, that will be the root of your misfire.
> 
> My sons S10 with a 4.3 kept throwing a P300. A new distributor cured the P30, but promptly got a P304. The distributor drive gear was worn and would wobble on the cam gear causing a P300. But I kept getting the P304. New plugs, wires, fuel injector spider, etc. Kept getting P304. Drove me nuts. Would only come on when the A/C got turned on. If AC was off and drove very gently, no code. Finally after listening to other people, pulled a compression test and sure enough #4 was low. Burnt valve. Root cause was leaky intake manifold gaskets caused a lean condition. I had the heads rebuilt and it runs smooth as silk with 245K miles.


I scheduled the service visit on sunday. I'll keep you posted. 

@sparkman yes.


----------



## EricSmit (Dec 21, 2016)

Cracked piston.


----------



## jblackburn (Apr 14, 2012)

EricSmit said:


> Cracked piston.


Dangit, GM.

Jerry said he runs his tunes fairly rich on these too.


----------



## EricSmit (Dec 21, 2016)

jblackburn said:


> Dangit, GM.
> 
> Jerry said he runs his tunes fairly rich on these too.


He does.


----------



## sparkman (Oct 15, 2015)

So, is it under warranty or is it out of your pocket because you had a tune?


----------



## sailurman (Sep 29, 2016)

Injector staying open. Misfires when low RPM but runs fine when under full load when it needs full flow. Stop driving it and get it in to get fixed under warranty before you F up a piston.


----------



## EricSmit (Dec 21, 2016)

sparkman said:


> So, is it under warranty or is it out of your pocket because you had a tune?


Warranty. Didn't even question it. It's a known issue.


----------



## EricSmit (Dec 21, 2016)

sailurman said:


> Injector staying open. Misfires when low RPM but runs fine when under full load when it needs full flow. Stop driving it and get it in to get fixed under warranty before you F up a piston.


Nope, cracked piston.


----------



## IndyDiesel (May 24, 2015)

That's pretty disappointing to have a cracked piston so soon. But does support my theory when having a problem while under warranty let dealer diagnose the issue. Yikes that would be expensive outside of warranty.


----------



## JRB'sOilburningCruze (Feb 25, 2015)

EricSmit said:


> Cracked piston.


Sorry to hear that. The good part is, it is under warranty. GM's problem and not yours....


----------



## EricSmit (Dec 21, 2016)

An update, because I'm never one to leave information unobtainable. Cracked would seem to be an understatement. Chunk of piston number one decided to be somewhere else. Warranty covered the entirety of the repairs.


----------



## jblackburn (Apr 14, 2012)

So is that suggesting a small air or vacuum leak could have cause it to run lean?


----------



## EricSmit (Dec 21, 2016)

jblackburn said:


> So is that suggesting a small air or vacuum leak could have cause it to run lean?


No, I think it's just saying that the unmetered air leak or vacuum leak could be a common conjunctive problem.


----------



## jsusanka (Jan 31, 2011)

thanks for the info and pictures. gm really needs to rethink their piston supplier.


----------



## carbon02 (Feb 25, 2011)

Thanks for the pictures, always fun to see things apart. I'm assuming the oil pan is off the bottom? How is the engine supported? As the entire airbox side of the engine is open. 

Is there an engine support on the GEN2 1.4L passenger side like the GEN1? I'm guessing the tech must have something under the bottom of it, but with having the oil pan off for access I'm guessing the support pad head must be fairly small. 

Wow the effort.. Does GM use some type of inserts with the head gasket bolts going into aluminum? The older GM northstar engines were notorious for stripped threads when reinstalling head bolts. Hopefully GM addressed that issue now that we're back to dealing with aluminum blocks.

Hopefully the threads are designed for multi use, and better than the earlier versions where Time-Serts were required when doing head gasket replacement.


----------



## EricSmit (Dec 21, 2016)

carbon02 said:


> Thanks for the pictures, always fun to see things apart. I'm assuming the oil pan is off the bottom? How is the engine supported? As the entire airbox side of the engine is open.
> 
> Is there an engine support on the GEN2 1.4L passenger side like the GEN1? I'm guessing the tech must have something under the bottom of it, but with having the oil pan off for access I'm guessing the support pad head must be fairly small.
> 
> ...


There is a mount on the passenger side. He didn't have anything under it. 

I am unsure about the head bolts.


----------



## EricSmit (Dec 21, 2016)

And just like that, we're back in business.


----------



## sparkman (Oct 15, 2015)

Sometimes I wonder if GM ever tests anything before releasing it....lol

Good to hear you got your car back.


----------



## MyLonewolf25 (Dec 23, 2016)

Dam, that sucks 

Glad it was covered


Sent from my iPhone using Tapatalk


----------



## Boostpatrol (Jul 30, 2013)

Interesting. My car has 3k on it and misfires like crazy at idle. Wonder if it too have unmetered air


Sent from AutoGuide.com Free App


----------



## EricSmit (Dec 21, 2016)

Boostpatrol said:


> Interesting. My car has 3k on it and misfires like crazy at idle. Wonder if it too have unmetered air
> 
> 
> Sent from AutoGuide.com Free App


Just take it directly to your dealership of choice. Do not pass go, do not collect $200.


----------



## ethangsmith (May 7, 2017)

Something of note- I see your VIN starts 3G. Mine starts 1G. This would indicate your car comes from Mexico, whereas mine is from Lordstown. I would be interested to know if this problem only plagues the Mexican built cars or all Cruzes. Until recently, I worked as a parts manager at a Kia dealership and often quality problems or defects were traced back to one plant only. Also, I thought all Cruzes were made in Lordstown? Glad I got an American made one. My Fiesta from Mexico was garbage.


----------



## EricSmit (Dec 21, 2016)

ethangsmith said:


> Something of note- I see your VIN starts 3G. Mine starts 1G. This would indicate your car comes from Mexico, whereas mine is from Lordstown. I would be interested to know if this problem only plagues the Mexican built cars or all Cruzes. Until recently, I worked as a parts manager at a Kia dealership and often quality problems or defects were traced back to one plant only. Also, I thought all Cruzes were made in Lordstown? Glad I got an American made one. My Fiesta from Mexico was garbage.


All the hatches are from Mexico. I didn't want a sedan, but I did buy my girlfriend one. But no, it's not only an issue with the hatches. All Cruzes are affected, but I imagine only the earlier build date.


----------



## ethangsmith (May 7, 2017)

Interesting. My Cruze sedan was built 2-17, so it's pretty fresh. Bought it in April, so it didn't sit long. I've also switched to 89 octane fuel. Seems to run smoother already.


----------



## 17Hatch6MT (Dec 28, 2015)

Boostpatrol said:


> Interesting. My car has 3k on it and misfires like crazy at idle. Wonder if it too have unmetered air
> 
> 
> Sent from AutoGuide.com Free App


Same here. Watching with interest. Hatch delivered to me late Nov. 2016. No mil/cel. Sometimes idles smoothly, sometimes not. Have always used regular 87. I don't think that 87 should impact idle performance...?


----------



## jblackburn (Apr 14, 2012)

Mine runs strangely on a cold start, especially the colder outside it is. Warm idle is fine.


----------



## ethangsmith (May 7, 2017)

Mine is the exact same way- it idles rough at cold start, but once it's warm, it idles nicely.


----------



## AuditorBill (Jan 6, 2017)

Geez, guess I'll start using 89 octane. Mine was built in Dec. '16. No idle issues, but the stop/start does do some funky things I think...like start back up with my foot still on the brake when the A/C is on--sometimes.

I know this is 'thread drift' but the A/C smells funny at times too. I didn't say anything but my daughter thought so too, commenting on it yesterday. It's not the typical musty/moldy A/C smell, but I really can't explain it.

When I heard about the Malibu turbos cracking pistons, I sent an email to my Service Manager. He told me no Cruze issues like that. Well, apparently GM is admitting it now. 

My '11 Malibu had some serious powertrain repairs required while under warranty, and I thought by now, with Mary "No More Crappy Cars" Barra in charge, that kind of thing would be in the past. Sadly, it appears not.

I would hope that Brian Sweeney is checking in here from time-to-time.


----------



## jblackburn (Apr 14, 2012)

> No idle issues, but the stop/start does do some funky things I think...like start back up with my foot still on the brake when the A/C is on--sometimes.


Normal. Once the evaporator warms back up, it restarts to maintain cabin temp. 'Eco A/C' mode (green A/C light) will change that start-up behavior slightly by allowing it to get a little warmer before it restarts.



> I know this is 'thread drift' but the A/C smells funny at times too. I didn't say anything but my daughter thought so too, commenting on it yesterday. It's not the typical musty/mold A/C smell, but I really can't explain it.


Changes during shut down and you start to feel/smell more humid air as the evaporator warms up. You'll probably get the same smell if you switch to fresh air and manually turn off the A/C while keeping the blower running.

The one weird thing I have had mine do - like 3 times ever - is that on a hot day, it will restart the motor, then there's a noticeable RPM dip where it about feels like the car is going to stall, then recovers. Happened once while sitting in traffic on a 95* day, once after just starting the car and coming to a stop with A/C off, and once in a drive-through with A/C running. I don't know if it was something EVAP-system related, something like vapor lock, the engine fan starting up, or just an engine management quirk. Couldn't get it to re-occur if I wanted to.


----------



## ChevyCanuck (Sep 27, 2016)

Hey folks,

Does this cylinder misfire make itself known through sound? Twice today I heard what I think is awful knocking or pinging. It happens when the car is in high gear, low rpms and i try to accelerate. I hear a crackling noise from the engine for a second or so. I let the gas go immediately for fear of causing engine damage. No CEL codes issued

FFIW I run Shell 91. 12000 KM on the odo. Anyone else experience this? It's happened 5 time or so now. Always when there's a high load (lugging) on the engine ; ie, acceleration or climbing a steep hill.


----------



## EricSmit (Dec 21, 2016)

ChevyCanuck said:


> Hey folks,
> 
> Does this cylinder misfire make itself known through sound? Twice today I heard what I think is awful knocking or pinging. It happens when the car is in high gear, low rpms and i try to accelerate. I hear a crackling noise from the engine for a second or so. I let the gas go immediately for fear of causing engine damage. No CEL codes issued
> 
> FFIW I run Shell 91. 12000 KM on the odo. Anyone else experience this? It's happened 5 time or so now. Always when there's a high load (lugging) on the engine ; ie, acceleration or climbing a steep hill.


Don't do that.

hahaha, but no, I was cruising on the freeway at 70 and when I got off the freeway and stopped at a light it was misfiring.


----------



## ChevyCanuck (Sep 27, 2016)

EricSmit said:


> Don't do that.
> 
> hahaha, but no, I was cruising on the freeway at 70 and when I got off the freeway and stopped at a light it was misfiring.


Ok thanks! Phew. I'll start another thread with regards to the noise if it gets too bad.

BTW I have the 6 speed Auto, it's the one that decides which gear I'm in lol  I'm not purposefully lugging the engine.

Cheers!


----------



## jblackburn (Apr 14, 2012)

My car hiccuped under moderate acceleration on 87 once. About 3500 rpm, I heard a weird cough from it and power cut out, then came back. 

I don't run 87 anymore, and it hasn't done it since. But even on 93, just like the first gen Cruze, sometimes in hot weather, low RPM power delivery can be a little jerky at times (2k or so, right when it should be hitting peak tq).


----------



## anthonysmith93 (Jul 15, 2015)

jblackburn said:


> My car hiccuped under moderate acceleration on 87 once. About 3500 rpm, I heard a weird cough from it and power cut out, then came back.
> 
> I don't run 87 anymore, and it hasn't done it since. But even on 93, just like the first gen Cruze, sometimes in hot weather, low RPM power delivery can be a little jerky at times (2k or so, right when it should be hitting peak tq).


I agree with this definitely, hot weather, AC on and my gen 1 feels like its chug-a-lug-n along haha


----------



## ethangsmith (May 7, 2017)

Yep my 17 jerks a bit when it's doing some heavier load low rpm running. I think that's just the nature of the beast and nothing to worry about. I've switched to 89 octane and it seems a bit more jerky, but overall better running.


----------



## ethangsmith (May 7, 2017)

In driving in hot weather today, I slowed to take a turn and upon acceleraton, the engine bogged down and you could hear the crackle of pinging in the engine. Maybe 89 octane isn't enough??? Should premium be used in these engines?


----------



## DavidGXP (Nov 26, 2016)

If it's a lean misfire. Premium won't fix this issue. It would be interesting to run some data logs that record engine load, ltft,s and spark advance/retard


----------



## jblackburn (Apr 14, 2012)

DavidGXP said:


> If it's a lean misfire. Premium won't fix this issue. It would be interesting to run some data logs that record engine load, ltft,s and spark advance/retard


Plausible for sure, considering that it has only happened on cyl #1.


----------



## Pipelineops (Jul 16, 2017)

34000 mi
Replaced #1 & 3


----------



## 17Cruzer (Apr 18, 2017)

DavidGXP said:


> If it's a lean misfire. Premium won't fix this issue. It would be interesting to run some data logs that record engine load, ltft,s and spark advance/retard


Engine load! Final gear ratio is high & elevated coolant temps. Down shifting a gear or so when accelerating may help. 

@OP...were all piston tops uniform in coloration?


----------



## JorgeMichigan84 (Feb 1, 2016)

Quick question... I think im having the same issue you had ( sometimes I floor it and it kinda hesitates to take off, mostly between 2k and 5k RPM's on 3rd or higher gear ) . I also have the AEM CAI installed as you, do I need to replace it with the stock box in order to take it to the dealership? I don't have a tune on my hatchback. Running 93 octane gas.


----------



## jstahliv (Apr 13, 2016)

I just had this happen a day ago. Service stabilitrak and engine code indicating misfire in cylender 1. Anyone fix their issues and figure out what it was. got 47k on 2012 1lt 1.4l Thinking about changing plugs just have new ones with grease on them. runing 93 octane only for months


----------



## ChevyCanuck (Sep 27, 2016)

Hey jstahliv this section of the forum is for Gen 2 Cruzes so 2016.5 or higher. Your 2012 has a different engine so it's likely a different issue.


----------

