grumbling

What might be the deep grumbling sort of compressor noise that I hear from my engine? It goes off periodically, doesn't seem to be connected with any particular thing that I do. Car is a 2004 E320CDI.

Been doing a bit of googling and got a bit confused. 2004 on a 53 plate R170 200 SLK Kompressor There seems to be a general impression that these superchargers engines can be a bit on the noisy side at tick over, especially when hot? Some people talk about a clutch mechanism that spins the...

Hi to everyone looking at my first post. I have a 2004 w211 e320cdi and have noticed an intermittent rumbling usually whilst towing that appears to eminate from the gearbox and on a couple of occassions with a surging of the vehicle. There is no loss of power associated with the noise but when...