One problem related to engine failure has been reported for the 2011 Audi A4. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2011 Audi A4 based on all problems reported for the 2011 A4.
This past Sunday, my Audi self-accelerated in busy traffic. Only because I drive a manual was I able to prevent an accident. I had the car towed from sacramento CA to Audi oakland. They diagnosed it saying the piston blew threw the engine, depressurizing the engine. They claim the don't know why and have failed to contact me since. I had to contact Audi USA which hasn't been responsive. This was a catastrophic engine failure while I was driving three boys. Nonetheless, Audi oakland--and I had to call them!--just told me its my problem and I need to pay $16k for a new engine. They told me this is an odd occurrence and since there's no warranty, its not their problem.