[CJFusco]

Pulling into my driveway today in the Cayman S, I heard a weird metallic "pinging" sound coming from the front passenger side of the car; it sounded a little like two metal coat-hangers clacking together.

A visual inspection showed no problems. Since the sound coincided with the car moving, I decided to jack up the passenger side and rotate the tires by hand to see if I could replicate the sound.

Sure enough, I got it on the first try: turns out that there's something INSIDE THE TIRE rattling around in there. I'm guessing that when I'm driving at speed, the centrifugal force is enough to keep the little bugger pinned to the outside wall of the tire, but at low speeds it's just bouncing around against the tire and the rim.

Who knows what it is or how it got in there; my guess is that it's one of the TPMS sensors that came loose (I deactivated the system long ago), but I suppose it could be a wheel weight? If there are internal weights in these rims, the recent increase in heat or humidity might have caused the adhesive to come loose, I suppose.

Has this ever happened to any of you? Needless to say, I'm swinging by the local tire place to have them remove this object (and re-balance the wheel, if need be) tomorrow.