Violently Jerking When trying to Accelerate when already moving

[studio3k]

2010 Camaro 2SS RS Automatic 400HP
The car is bulletproof nine days out of 10 and I love it overall...BUT a major deal breaker had I found this out on a test drive (bought it sight unseen w/o a test drive and this happened first on the way home from the dealer)....when I go to accelerate usually coming out of a turn the whole car violently jerks 2, 3, 4 times and will not accelerate unless I take my foot off the gas and go again....if it starts to jerk and I put the pedal to the floor (tried it once) the car jerks more and the tires actually start to squeal like its trying to go but something is stopping it....happens on wet or dry pavement, traction control both on and off, engine warm or cold....happens usually coming out of turns but have also noticed on straight stretches. Will happen from a dead stop but I notice it more from rolling stops...never noticed it on extreme acceleration (where you might expect the car to loose traction) only gradual or moderate acceleration attempts. Main concern: I pull out onto a 55 mph road everyday and my car shakes, I can't accelerate and someone hits me from behind at 55+....that could put me in a body bag pretty quick....I was relatively close once but I was able to pull over and let the guy pass me...I SHOULD NOT have to do that in a 400HP vehicle and I had ample time for a normal car anyway.

I've had my car to the dealer 3 times (soon to be 4) but they've already written it off as a normal characteristic of the vehicle...I was able to duplicate the shaking in a brand new Camaro off the lot within 200 yards of the test drive...so they call it normal...but i don't want to die so I'm not letting that convince me....somebody help!!! I need an unbiased perspective what could this be. "

[Ivas]

Is the engine missfiring?

[ZED SLED]

Probably something to do with the AFM (going from 4 banger to 8) and maybe being on the crappy low octane table. Do a fuse pull.

[studio3k]

I wish I knew more about cars, but how would you tell if it's misfiring? It's been to the dealership and they claim that this is just normal?

[SlingShot]

Hmmmm ... Dealer ?

[Ivas]

The more I think on it, the more it sounds like you're losing timing when you punch it in the midrange. Does the same thing happen if you just roll into the throttle?

[OUR72GTO]

So take one of the idiots from the dealership with you and put it thru the same road.

[2010 SSRS]

Originally Posted by OUR72GTO

So take one of the idiots from the dealership with you and put it thru the same road.

[VTXrider]

I think they all do this to some degree when cold, maybe the first 2 minutes after a cold start. Other than this, no this is not normal! Find a new dealer!

[studio3k]

It can't be the cold, this happened after running the car for 20 minutes. But honestly I live in SWFL where the temperature was 70 degrees out.

[Russell James]

Is it in 4 cyl mode when this happens? I've driven a few automatics that hesitate a bit when slow coasting in 4 cyl then easing back into the throttle.

Especially if low octane fuel has ever been used in the car. The L99 has a problem of the ECM getting stuck on the low octane table. Look up the L99 fuse pull info, do that, then make sure to use premium fuel. Also check on the dash if it's in 4 cyl or 8 cyl mode when this is happening.

I'm also leaning towards it's AFM and possibly the fuse pull thing related.

The car has self diagnostics for misfires. If it ever actually misfires it will set a code and turn on the check engine light.

[warrior18]

My car does this also. Usually when I turn into the parking lot where I work.
This is after about a 15 mile drive that takes about 25 minutes with both city and freeway driving included.

[VTXrider]

This is definately not right. I would keep taking it to different dealers until you find one that doesn't have their head up their ass!

[jtzako]

I've had this happen now and then but I dont think it is the car, it is my foot that is doing it. I push the gas when rolling slowly such as for a turn and hit it harder than expected and reflexively back off a bit and it bounces the throttle.

If there is something weird the car is doing to cause this I cant figure out what it would be. It just feels like the accelerator is being pushed down then lifted a few times.