When leaving work (low speeds for several minutes) I noticed a very loud scraping sound coming from the rear. I had a co-worker join me to determine the exact origin of the noise; the driver's side rear wheel well. The scraping occurs at very low speeds and is noticible when the car is not in gear. It sounds like the brakes are scraping, but the caliper face and brakes appear to be fine and the noise sounds like it is coming from "behind" the wheel. Called a Porsche Mechanic aquaintance and he suggested that the E-brake may be sticking somewhat. Got the go ahead to drive home (19 miles all interstate). The noise went away once I got up to speed (45mph+) and didnt return, even when I slowed down. I dont want to pay for a mechanic visit that doesnt find anything wrong and I am going to have the wheel off soon to do a brake pad replacement. Has anyone experienced this before? Any thoughts on a cause?
I have a '99 with 111k miles.
Should only take ya a minute to pull the wheel and have a look-see in there. It's likely either foreign debris between the rotor and shield, or whatever debris impacted the shield bent it such that it's contacting the rotor. If you find something worse, then it may be time for you to call your shop back.
I've had the same thing happen a couple of times, rotor guard was contacting rotor slightly and made that noise. Once because I tweaked it slightly during a wheel mounting, and the other when a rock got in there during a drive.