Quote Originally Posted by annihilatorg View Post
I have a similar issue with my 2009 aveo lt, and I just passed 60k (I purchased mine used just 3 months ago at 56k)

I find that the 'bucking' will happen right AT 2000 rpm according to the tachometer. If, for instance, I am riding at 40-45mph (1500-1700rpm) and need to rev-up just a bit to go uphill or to accelerate the car will start bucking and the tachometer won't move above 2000rpm ON THE DOT (not sure on the gear, it's an automatic, probably 3rd). I almost think it's a firmware/computer issue where the car wants to down-shift, but the revs aren't high enough to allow it, so it just vacillates back and forth. Sorry, I'm a computer guy so I always blame software, even if it's not the issue... but a hard stop at a specific, exact RPM screams software edge case.

Oddly, the issue is brought on more frequently (to me) when the tires have low pressure... When I recently checked the pressure to be 28psi and inflated back to 33, the issue would happen much less frequently.

Anywho, I need to take it in for 60k anyway... so we'll see if the transmission is just being weird and needs some TLC or something else along those lines.
Hello Annihilatorg,

Sorry to hear you're having these issues also. Hopefully the dealer will be able to diagnose what's going on. Was the car having this issue 3 months ago or did it just recently start happening?

Vanessa
GM Customer Service