I have taken my car for service several times for the same problem. What was happening was the car engine would race, but the car would not go. I have actually put the gas pedal to the floor, and go no where. I was told it was the gas I was using. The other day it was so bad, all service light came on. I had the car towed to Riverside Audi Service. After 2 days of the car sitting there, I was told the matt was getting stuck. How stupid. I took the car home only to return it the next day. Now I was told it is the chip in the gas pedal and after replacing the chip, the car needs to be driven at least 50 miles before they can return it to me. So for 1 week now, I have no car. BTW, they don't offer loaner cars either. DO BRING YOUR CAR TO RIVERSIDE AUDI SERVICE. I will be looking into the Lemon Law.