[turbo23dog]

I had same problem. Never did find what or where it was coming from but one day on a hard turn it sounded like it left the car...( I know, sounds weird). I assumed it was some kind of debris that got hung up in the undercarrige, maybe on top of one of the plastic undertrays.

After first few times hearing the sound, I searched the door pocket as well as under the pass side seat where I did find a 1/4 full water bottle and a small screwdriver which I think were left from previous owner. You can imagine my disappointment and fustration a week later I heard the sound again.

At one point I did jack the car up and crawl under for a look-see but never got to the point of dissassembling the undertrays...