I continue to have poor low end performance on my 89 760 (104K miles). From time to time, the car pulls strong off the line, so I know it can perform. It seems to be performing like the spark is being retarded (turbo ramps up slowly and sits at full boost with minimal increase in accelleration) I know I'm in need of new motor mounts and am wondering if the knock sensor could be interpreting the engine vibration as knocking. I've also been getting poor gas mileage (16 miles/gal)which also directs me to a timing concern. Does this sound familiar to anyone?

Thanks for the time

Steve