98 E320 52000 miles. While in idle tapping sound appears to be coming from power steering pump. Turning the wheels in either direction at idle increases the sound. Above 1000 RPM the sound is not present. All other indications normal, no leaks, runs well.
Do these pumps have a history of failure? Thanks

 

have seen a few go bad not many especially at 52k. are you sure its not the belt tensioner pully?