96 328i I'm gonna suggest taking a look at your rear trailing arm bushings (aka RTABS). My car made a knocking noise over bumps until I replaced those. Now she's golden.
dab of oppo anyone?
Replace coolant temp sensor
Brake and Power Steering Fluid Flush
Front Control Arms, Bushings, and Tie Rods
Replace Passenger Lock Actuator
Reglue Peeling Hedliner