on my dad's car, when they reinstalled the tire, they did not install the tire cover correctly and it had play in it. So whenever the wheel turned while driving the cover would make a tick-tick-tick sound in sync with the speed of the car.

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1996 E320
2000 C230 Kompressor
1988 190e 2.3 - 225K miles, owned for 7 years. I cannot say enough good things about this car. Very well built, even at 225 it ran like new.