2004 Mercedes Benz C240 Base 12Cyl6.2L - Steering & Suspension
Solution Sought for Power Steering Noise at Idle only
Power steering pump will make a rattling (marbles in a can) moise at Idle speed, a bit worse in gear but ONLY when the A/C compressor is OFF. As soon as the A/C compressor is turned on - everything stops and sounds normal. Tensioners and idler pulley replaced. The sound can also be stopped by increasing idle about 50 RPM. System works well, oil not contaminated. Sounds like bad tentioner bearings when sound is heard. Definately coming from power steering pump. Does anyone have a solution?