newtonlaw

I am getting a very weird "ei ei ei ei ei ei" noise that never goes away from the engine at idle to about 2000rpm. At higher rpm the "ei" noise repeat faster than at idle. it sounde like a 10yr old car. sounds like somthing with the belt?

Diesel Benz

Did you search this forum for similar posts? I tend to remember someone having something similar, from the serpentine belt or tensioner.

shag

Must be MB's new feature - FONZIE-TRONIC

C300Sport

Is that a 2009 feature...gotta have it!!

Furuso

It seems to come from the left front next to driver's door. the noise goes away when I turn off the A/C so I think it has something to do with the A/C.

C300Sport

If it only occurs when the AC compressor is running, does it sound more like a pressure leak or a belt squeak? Since NewtonLaw's squeak never goes away, it may be the AC compressor clutch(if these are the same sounds)

Diesel Benz

But there should be no AC clutch, I don't think MB has used a clutch type compressor for years, these run continuously (but compression can be switched off by control valves).

I also noticed an old document about noise from the compressor area, but I would assume this concerning older W204 cars.