[Templar]

Just had this happen to me this week. Washed the car on Sunday, had the noise on Tuesday. It went away and then happened again yesterday afternoon. I called BMW in Midlothian here in VA and asked them if I could bring it by for them to hear it, but of course by the time I got there it had stopped. They told me to take a log of when it tends to happen and if it keeps happening to bring my log to them and schedule an appointment.

I figured I would let the car sit for a few hours at home, cool off, and then try it again at night. I tried it and no sound, so I figured I'd wait more to see if it did it this morning. Bam, did it again this morning pulling out of the same spot it was left in all night. Drove it to work and it seemed to stop. I'll try it again at lunch and see if it does it again, but in MY case it seems it might be the e-brake and not a rock. It's the same pinging, hollow, empty tin can sound coming from the rear driver side wheel area.

I did the same thing, freaked out and went underneath the car to see what was hanging from it, but found nothing. Nothing was loose or anything when I pushed it with my screwdriver. No issues when driving on the highways (the sound only occurs when pulling out of a parking space going at low speeds).

Tomorrow when I have time I am going to take the thing apart and see if I can either find a rock or adjust the ebrake spring and see how this pans out. Will post an update here. If it still doesn't go away I'll take it to the dealer and let them figure it out...