One problem related to engine exhaust system has been reported for the 2013 Audi A8. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2013 Audi A8 based on all problems reported for the 2013 A8.
While driving on I-20 in texas the epc light came on, engine power decreased noticeably. Limped off I-20 to an exit. When I stopped at the stoplight at end of ramp, engine quit. I tried several times to restart. Nothing but sputtering. Fortunately, I found that slight pressure on the accelerator while cranking would start engine. Engine would not run below 1000 rpm. Very dangerous having to keep engine running while navigating city streets. This engine has had a series of recalls, including an oil separator failure. Audi TSB, attached, finds an oil sieve responsible for starving the turbochargers causing my vehicle to fail without warning on the freeway at 62,000 miles. I have kept the failed parts including both turbochargers, one wobbling and the other completely separated on the exhaust side. This is a clear danger to vehicle and occupants. This very expensive repair warrants a NHTSA recall.