stutter / shudder, holding back, popping sound
 

My problem, and I will try to be as specific as possible, but maybe i do not use the right words because my technical English is not that good.....

2 months ago I bought a new 2018 Camaro 2.0 Turbo (6th gen.). After a few weeks the engine started to stutter and did not accellerate. It also made a "popping" sound during acceleration. I drive away slowly to the end of the street (a hundred meters, more or less, in about 20 seconds) and accelerate. Then the engine starts to stutter, does not accelerate further and makes a "popping" sound. After 3 or 4 seconds everything is mormal and the problem is gone and does not occur again. It does not matter if it is rainy or the sun is shining, hot or cold weather conditions, it always occurs. And it does not matter or i drive in manual or automatic. It is fully stock, no modifications. The engine warning light never turned on and they can not find error codes in the motor management computer. Tries several brands of petrol and filled the fuel tank with Euro 95 and Euro 98 but this had no effect at all. The Camaro dealer doesn't think it is a fuel issue.

The official Camaro dealer where i bought my Camaro, updated the software first, replaced the spark plugs and the cables, replced the coil pack (bobine), replaced the injectors and replaced the computer for motor management but the problem is still there. My Camaro dealer is an official distributor and they looked in the database of Chevrolet but my problem is unknown and they do not know how to help me :-(

Because my Camaro dealer doesn't know what's wrong and GM can't tell them anything, i have been experimenting by myself.
The results:
- The problem occurs in tour and sport and in manual and automatic and weather conditions do not matter.
- driving away "fast" instead of slow, largely solves the problem but it is not very neat to drive away "fast" in a residential area in the morning.
- driving away in manual, in second gear, also largely solves the problem.
- starting the engine and hitting the pedal till about 4000 rpm once or twice makes the problem less but it is not totaly gone. But hitting the pedal once or twice in the morning is also not very neat to do in a residential area.
I would like to add an MP3 file but i think it is not possible to upload a "sound file".

I hope someone has an idea or a suggestion because it's driving me crazy.

Are there maybe persons active from GM at one of these forums who can also look at my problem?

Are there any sensors in the car which adjust the fuel mixture, making it possibly too rich (or maybe to lean)? The "popping" sound i hear looks like fuel igniting in the exhaust or a misfire.

Thank you in advance.

Only thing I can think of is have your dealer check Document ID: 2836149
It addresses a shudder on acceleration at low speed.
The driveline center bearing splined shaft angle may be excessive or incorrectly set, audible binding has been noted, and may be heard.



Would fit your description, and also would not have any DTC's set or SEL set.

Almost sounds like a MAF sensor going bad or a possible wiring issue to it. Has the car ever had any work done or been in an accident where it was repaired?

Sounds like a bit of coops and a bit of the infamous A8 shudder.

Thanks, i will communicate this with my Camaro dealer.
More advice is welkom because they already tried a lot of things.

@Evil-Bee-NH,
My technical English is not that good, so please can you explain what you mean with "coops" and the "infamous A8 shudder". Thanks you.

@Nsxmatt,
I bought the car new, so i asume it did not have an accident ;-)

Part of what your describing sounds a lot like A8 Transmission Shudder it happens at both low and high gears on light throttle where transmission line pressure goes to low. It can damage your torque converter their are several GM band-aid fixes out but tje only real concrete fix is to zero out slip% tables in your TCM. Which will void your warranty unless your dealer is extra polite.

I went to my Camaro dealer but none of the above causes the problem they say :-(
So, if someone has other / more ideas.......: i welcome your advice.

Try a brake torque if popping sound is there it's got to be a missfire.

Did you ever figure out what was going on with your car? I worry I have the same issue as you. Sometimes when I am leaving home the car pops and shudders. The transmission also acts really weird sometimes and holds gears a long time.

Hello Ray-J,
No, sorry, the Camro dealer does not know what the problem is, they are out of options.
Do you also have a 4 cilinder turbo? And is it a new one?
Meanwhile i have driven about 3500 kilometres and a few times (on a quit road) i accelerated a few times as fast as my Camaro could. I think the problem is a bit less as before.
The only thing which work is if you drave away "fast". I do not mean with spinning wheels but faster than you probably would or should do in a residential area. Or driving away in second gear.
Maybe do you know if there is a possibility to contact GM directly as a consumer? Probably not....

Not from belgium prolly not. It's likely your A8 shudder has damaged your torque converter.

Hey there just saw your post. Not sure what version of the 4 I have but I purchased it in early July and it is a 2018. Mine doesn't do it often but it does do it. I do what you do and that is gas it a little to get it to go away. Also sometimes my RPMs are way to high so I shift it over into manumatic then back and it goes back to normal. I am so mad that I did not just go manual.

Yesterday the MAF sensor has been replaced.......... No results :-(
The car is driving me crazy with this problem........ :-(

The Camaro dealer told me that the 2018 model has an other computer for the motor management then the 2017 model. Mine is a 2018 model, so i am wondering if the computer for the motor management has an other program on it because my Camaro dealer says that they have no problem with the 2017 model but that they have 2 2018 models with "my" problem (and one of it is mine....).

Yea this suck. It did it to me the last two days that I have been leaving home in the morning. When putting it into drive the car hardly moves. I apply more gas and then it pops and sputters. Takes about 15 to 20 seconds to go away. Seems like something we have to live with until someone finds a fix.