So I started hearing a clicking noise coming from the engine, usually in the morning when I first start the engine, and mostly right when I put the car in reverse to pull out of the garage. The noise is intermittent and is not proportionate to the engine RPM. It's just random clicking. It lasts for a few seconds and then stops, even if the car is still in reverse. I have not been able to reproduce this problem when the engine is warm. I have also not noticed any problems in the car's performance.
Took the car to the dealership (after work) and of course we could not reproduce the problem. They kept the car for a few days and started it in the morning every day. On a couple of occasions, they DID hear the clicking. However, since it only lasted a few seconds, they could not locate the source. They involved BMW (PUMA I think) to no avail. They decided to give me the car back. I'm supposed to go back if the problem gets worse. BMW is "investigating".
Has anyone had a similar issue? Any ideas what the problem could be? I appreciate any help with this.