Engine Grinding Noise problems of the 2013 Audi S6

Car suddenly had a "rough idle", I. E. Shaking 1-2inches back-and-forth while in idle, after driving for 20 minutes at normal conditions. Shutdown car. Attempted to restart car, but the engine would not turnover the first attempt. Tried again - engine started the second time. No check engine light appeared, so I assumed car was safe to drive. Drove car to dealer for service, and then I noted that the car started making a feint grinding noise when accelerating. Technician noted that both turbochargers had failed, likely due to inadequate oil flow. Car has 60k miles on it, so a catastrophic turbocharger failure this early-on was unexpected and potentially dangerous (car could have stalled due with engine being starved for air), and no check engine light appeared to indicate something was severely wrong with car. . Read more...