I'm bringing in my 2011 Aveo into the dealership tomorrow morning for the same thing. I have no acceleration at times around 30 mph and consistent "bucking" at 45 mph. It's pretty scary experiencing this on the highway
. The first time I took it in was around 60,000 miles. Replace my plugs, and cleaned my throttle body for maintenance purposes. No codes at all. Everything seemed great at first, then it all came back again. I'm asking them to check my cat converter and
O2 Sensor while I'm still in my Emissions Warranty. Hopefully this will do the trick! I'll be sure to keep everyone updated!