2013 Audi A6 engine problems

I was entering my garage and the car kept accelerating. I slammed into any front wall doing lots of damage to the structures in and out as well as to my body. My car was totaled. My first accident ever and the scariest moment of my life. I have had prior acceleration/deceleration issues with this car. On at least 6 occasions, I was going downhill approaching a stop sign and the car seemed to stop responding (steering, braking, engine) and yet the rpm's were gong higher and the engine was racing.

Vehicle began shaking, driving very rough and check engine light came and epc lights came on the dash. Car was not drivable. This happened less than two months after I had the water pump replaced for leakage and failure (which has now been recalled). I believe the two are connected, but audi charged me a to replace the engine. I feel that the engine failure was a direct link to the issue with the pump.