Purchased vehicle on 9/6/2012 used with 27,479 miles. On 9/19/2012 with 27,960 miles, I was accelerating on an onramp getting on a highway and two messages appeared on my dash: "reduced engine power" and "service traction control as well as the check engine light. Experience rough and hesitant shifting between gears and could not go faster than 35mph. Was able to safely navigate home on side roads. I took it to the dealer I purchased it from for service and was told it was reading code P2138 and the throttle pedal assembly needed to be replaced. The service was covered under the dealer's warranty and I was set to go. Flash forward to 10/24/2012 with 29,355 miles, I was driving on a side road and the same messages came up. I called on star and they performed a diagnostic which resulted in the computer reading codes P2138 and C0242. Experienced out of control wheel spinning and sensitive braking. Took it to a dealer in the area I was currently in traveling for business and they could not diagnose with any issue. All codes and lights were not engaged. I still did not feel safe driving my vehicle due to problem with accelerator and had towed to the purchasing dealer near my home. They also could not diagnose with any issue as they could not duplicate the error. This is a serious safety concern and a problem (especially on the highway) with a popular model. I have also filed a complaint with GM on this issue and am hoping to have it resolved immediately.

- Portland, ME, USA

I was turning left into a driveway going no more than 7 miles an hour, because I was following a car, when I heard a large grind then pop. I parked my car and knew immediately the transmission failed by the fluid trail and part left behind. I took it to a dealer and luckily it was covered under the power train warranty. A week after receiving my vehicle back the alignment was off, driver-side headlight socket caught fire, I have labored start up, have stalled on the freeway! and have stabilitrak, airbag, and reduced engine power error codes that randomly appear.

- Whittier, CA, USA

Car stalled on the interstate. Merged car to break down lane without being hit. Traction control light illuminated. Car would not restart for about 20 minutes. Car then restarted and warning light was off. Previous electrical issues with this vehicle including rear windows that will not roll down and defective air bag sensor.

- So. Strafford, VT, USA

The contact owns a 2009 Chevrolet Impala. The contact stated he had experienced brake failure since the date of purchase. When the brakes were applied, the pedal would pulsate abnormally. The brakes would also make an abnormal noise similar to scraping metal when applied. The dealer replaced the rear rotors and brake pads three times but to no avail. In addition, the contact also stated when the gear shifter was placed in park; the vehicle was able to drift forward and backwards. The vehicle was not diagnosed for the failure and there were no further repairs made to the vehicle. The failure mileage was 8,143 and the current mileage was 17,009.

- Beaver Falls, PA, USA