I agree its probably the motor mounts, with 150K they are done. My daughters car did the same thing. The shift knob would make your hand go numb, I put new BMW motor mounts in and its smooth as glass now. I think it was about $200 in parts and about 2 hrs messing around in the garage. The motor sit quite a bit lower in the engine compartment before with the bad mounts and now with the new mounts it lifted it up about 1/2" and her air box lines up better.