I have a 2022 C8. Just after the 500 mile limit was off I have a stutter at light throttle around 1500 rpm. I took it to the dealer and the Corvette tec said I may have bad gas or transmission learn mode! What? I have ran another tank of gas through and it still does it. In manual mode one gear it still does it. It feels like transmission momentary slip and catch. It throws no codes and if you hammer it does not do it. anyone hear of this?

 

Did you ever get this resolved and if so what was the issue? I have just over 8k miles and car has been flawless and I've modded it slightly. 2M cats, Atak blue filter, Lingenfelter intake manifold and throttle body....the car has run perfect! About a month ago it started stumbling and hesitating when driving and accelerating, but only after a few miles of driving and all fluids getting to up over 170 degrees. Runs fine prior to that and idles fine. Strange thing its run fine w/ all these mods for close to a year, just started doing this out of nowhere, almost feels like a vacuum leak but it wont do it for a few miles after starting, everything has to be warmed up but no cel coming on.

Taking it in monday to have dealer run some tests/scans, almost seems its some sort of sensor since it doesn't do it till its fully warmed up. Curious if anyone has any ideas and if OP found a resolution.

 

Never have. Dealer said just drive it. Only have 900 miles on it. It is better but not cured.

 

Have you checked through the spark plugs?

 

My symptoms are similar, interestingly I had a Pedal Commander on and it masked the problem to some degree. I took it off just to see if it was the issue and the problem seemed worse, almost like the PC was allowing more air to pass by or something along those lines. The car doesnt do it when cold and before all fluids hit about 170 degrees either. Will be interesting to see if its a sensor of some sort with mine, going into dealer this am. Will report back once I know, well really hoping they can find the issue as there is no cel and OPs post worries me a bit.

 

Please report back this could be helpful for others. As I have not noticed this on mine I have heard others mention it and recall something about the cyld 4 spare plug / coil. But this was more of a skip misfire maybe similar to a stutter?

 

car still at the dealer, been 3 days and they cant find the problem. All tests and scans come back ok and car is showing its symptoms. They put in a help ticket to gm and they are stumped as well. Going to do more testing today and try to reset some things but all fuel trim levels are good and no vacuum leaks. Has me worried they cannot find anything wrong, will report back when I know more.

 

Wow this is sounding interesting but not in a good way but maybe something to open the eyes of new trouble shooting for similar issues experiences.

Hope it isnt really anything and comes out ok. Keep us informed.

 

Yeah, its tough hearing daily they cant find the source of it. Being turned over to shop foreman today and if he cant find anything, next step is have a GM engineer come down to look at it. I do have an aftermarket (Lingenfelter) intake manifold and throttle body on it, those parts have been on for 4k troublefree miles but I know if an engineer gets involved they may not like that. Doesnt seem thats a cause of the issue but then again nothing is throwing a cel so hard to narrow this down and all their tests come back normal. They have run a vacuum (smoke) test and doesn't appear to be any leaks but that is what the car feels like symptom wise. We will see....

 

Been a couple months since I last posted but thought I would update it incase this happens to anyone else. I pulled off all my performance parts except my high flow cats so GM could get stock readings and an engineer was going to come out to see my car. First time in the dealer still no CEL and they reset the throttle body per GM and they thought it fixed it. It felt like it but 2 days later the stutter was back. Only at partial throttle, the car runs fine at full throttle and still pulls a 2.8 0-60 on the timer so performance is not being affected.

Took it back in and left it for a week, got escalated to a higher GM engineer, they thought it might be the trans but ruled it out after a couple of tests. They now think its the cam magnets and Im off 1-2 degrees on the test they did and will be pulling the engine this week to get under the timing chain cover to do the replacement. Hopefully this is it since Im tired of this issue and the car not running right although as OCD as I am the thought of pulling the engine causes a bit of anxiety lol.

If this doesn't do it, I will pursue a buy back and get a different car but really want this to work out and just have it working right. The dealer has done 3 engine pulls on C8's so at least this tech has some experience at it. Will report back in 10 days or so.

 

Damn!!
Hopefully all goes well, since I will have same mods shortly, definitely keep us posted.
Thanks

 

Any updates??

 

still waiting for all the parts they need to come in, thinking it will go in Tuesday he said yesterday. Keep you posted!

 

Wow all I have to say! I feel you though on that OCD and the thought of engine getting pulled! My thoughts are with ya and looking forward to the updates!

 

Well, the verdict is in.....after all this time and having the dealer diagnose my car w/ no codes thrown, me having to get stock parts and pull my mods off, have dealer do more tests etc, its finally fixed and was a bad (dirty)cam phaser or cam magnets that tell the timing what to do. The entire engine and trans, exhaust and subframe was dropped out of the car, oil, freon, brake fluid and coolant were all drained out. It was a 4 day job but it runs perfectly now. I am told its happening on other GM engines too, not just limited to the Corvette. What's interesting is I don't drive my car in any sort of weather, I don't spray the engine off, its never seen rain and I keep the car and engine spotless and in 9k miles have changed the oil twice yet I'm the one w/ dirt inside the timing chain cover? Service advisor said no rhyme or reason for it.

My hope is if anyone reads this and has similar symptoms, its an easier path to navigate than what I had to try to figure out. Im not the one who started this thread so maybe the OP will read it and it could help. Very happy w/ the job the dealer did overall, car is filthy and fingerprinted up worse than a FBI crime lab but w/ everything that had to come apart, I'm impressed. Even after watching the PDR footage which I admit gave me sweaty palms LOL. Now, I think Im gonna put my engine mods back on now....

 

Thank you so much for sharing this and hope it does help someone else out having similar problem. Your last statement was so funny but true. I guess its worth it now having a car that runs sooo much better. Seems like it was dirty in there during the building of engine.

 

What dealer did you go with to get all this done? Im still researching dealers for service here in AZ and most of the input is not good..seems like yours knows what they are doing.

 

I live in the west valley and have always used Gateway Chevrolet by 101 and I10. Service advisor is Zack.

Are they perfect? No, but overall im happy. Have a buddy who likes Van Chevrolet in Surprise but ive never been there.

 

Bumping this old thread....I have been having similar issues as MikeinAZ with my 2022. Seems like it only happens when the fluids get warm to hot, and under light acceleration from maybe 1500 to 3000 rpm. But the car "stutters" or "bucks". It feels like a miss or something.

I actually went ahead and had a local dealership do the DCT filter change since I have a little over 6000 miles on the car and it did it again on the way home. I have some PDR video that I'll show them that captures the rpm fluctuation.

So thanks for posting your resolution Mike. I'll post here hopefully in a few weeks with my update.

 

Hope you get it resolved, bring it up to them so they csn look up that particular issue and resolution. Glad you were able to read and remember my issue lol. Keep us posted partner.