On 8/27/2012 I drove off the car lot with 7 miles on my new car. I noticed a little bit of rough shifting as the day passed. On 8/28 the car started bucking and jerking during acceleration. There was little power on inclines. The problem progressively got worse through the day. I set up an appointment to drop off for service the next day. Took in for service on 8/29 and was told that the throttle body needed to be replaced. The car had 187 miles on it. On 8/30 I was told the car was fixed and I picked up my car. Within a few miles the problem was back, but worse this time. I had some slight noise coming from the engine when the car was bucking and jerking. It almost stalled on a busy highway in rush hour traffic on my way back to the dealer. It was struggling. The car is back in service with 220 miles on it. Now they want to keep it for at least 3-4 days. I'm totally scared to get back in this car ever again.

This vehicle is a bad example of how to do throttle by wire. There is a significant lag between the moment you step or release the gas pedal to the ECU supplying or cutting off fuel to the engine. This is fairly noticeable in two occasions:

1) with a manual transmission, when shifting fast, the engine overshoots about 500 to 1000 RPM right after releasing gas and stepping on the clutch.

2) when cruising in a parking lot there is always the need to accelerate and slow down, but when I remove the foot from the gas, it takes about a second for the car to react, all the while keeping the same engine power for that second. In emergency situations I often found that the brakes had to fight the engine still accelerating.

The problem that I have with this is that in an emergency situation, a second of full throttle could mean that my vehicle will stop a few feet ahead of where it would if the ECU cut power at the time I released the gas pedal.