Various bushings—located around the subframe, suspension, and steering—deteriorate with age. A clunking noise when driving over bumps, accelerating, or stopping may be a sign of worn bushings.Google+
Car Problem Reports
Audi S4 Bushings May Deteriorate With Age and Cause Noise
Audi S4 Problem
Average Mileage: 73,000 mi (36,000 mi - 110,000 mi)
Visitor, 1992 Audi S4, 36,000 mi
Clunking sound coming from driver front suspension when accelerating stoping or going over small bumps.
Clunk - starting/stopping hard or backing out with the wheels turned hard to one side