My brick is an 86 740 and these were OEM solid motor mounts that were put on about 2 years ago along with the tranny mount (by th dealer). These mounts should not be the problem as when the car is under 2900 there is no noise/vibration. I will rule out the knock sensor or see if that is the problem. Maybe it isn't adjusting the timing as the throttle is depressed--causing excess engine vibration. The only other thing that it could be is the flywheel (maybe out of balance)???

Also, when depressing the accelerator pedal (to what I think is the floor) and it doesn't accelerate as quickly as I think it should, all of a sudden, there is more pedal to depress. Almost like it gives way. Is there something that stops the throttle pedal until extra pressure is put on it to depress further? When I get this excess pedal travel, it seems as if the engine rpms jump from 2900 to 3500 instantaneously and the excess vibration/ noise is very noticeable. The car then accelerates appropriately. Is there a throttle pedal stop? This is just a very wierd condition that I don't think I've heard of happening before.

Thanks,