Hi guys 1998 C200 Classic Auto. VIDEO0001.3gp‏ - YouTube Check this out for a clearer explaination. Here's the problem I'm having. The Tensioner and pulley have been replaced, the older tensioner replaced with the newer one along with the damper, which isn't usually fitted to the 4 pots. So Tensioner, Belt, Damper and Pulley the goes on the tensioner all brand new. Febi parts and the belt is Motaquip. Yet under load, the tensioner is still struggling to keep the brand new belt tight, it wobbles back and forth and makes a terrible noise at idle particularly when the A/C is on or Drive is selected, it settles down in neutral or with the A/C turned off, the belt noticably slips in Drive when the power steering is moved and you can feel the power steering pump almost miss as the wheel is turned.