Hi to all, I have problem with my W212 facelift 200cdi 100kw engine 651.925
If is engine warm on operating temperature there is noise sounds like "dry bearing" or scratching on iddle speed
check attachment video please.
serpentine belt was removed bud noise is still there so this is in the engine.
Vacuum pump? Timing chain? Crank or camshaft bearing?
cold start is perfect, no chain rattle, no noise etc
Thank you very much for reply