One problem related to engine stall has been reported for the 2015 Audi A8. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2015 Audi A8 based on all problems reported for the 2015 A8.
Engine stalled in traffic and car would not restart. Car was operating normally, pulled up to a red light to turn left on to busy 2-lane highway. Engine began sputtering and car lurched forward. Light turned green, was able to turn left on to the road. I got 1/3 mile down the road and the engine stalled completely and would not restart on multiple attempts. Car was disabled and stuck in traffic. Car towed to dealer. Dealer diagnosed failed turbochargers. Car had 68,800 miles on it at time of turbocharger failure. Car was serviced at Audi dealer for every service interval per manufacturer recommended mileage-based intervals. Car/engine has not been modified in any way with aftermarket parts.