One problem related to engine clicking and tapping noises has been reported for the 2006 BMW 750. The most recently reported issues are listed below.
When I was in park put car in reverse and car would not go in reverse went back into neutral on its own , so I put car back in park and retried and put it reverse several times and when the transmission kicked into reverse there was a large clank sound and a jerk that felt like I had been hit from behind , when stopped at red light to take off same thing the car jerked again . Then transmission fault light came on stated drive moderately, and another warning came on stating certain gears were not working correctly . Parked in garage and after several attempts the car did the same thing , vehicle was taken to local dealership for inspection and diagnostic testing to detect problems .