Get the codes.
I still believe its electronic and the ECU is putting the car in limp home mode. Yours is AWD, so it could be a tranny safem mode...
Guessing isn't helpful, get the codes.
So to recap, the car always loses power when you turn into corners and never at any other time?
Did I mention to get the codes?
Need an s54 MZ3 coupe...will trade...