150shot

Did a search but nothing solid...I have a humming type noise that is constant while at idle, I just noticed this weekend. NOt very loud but is noticeable and I dont think it was constant before..

Humming gets a bit louder as I raise RPM's, I'm thinking it has something to do with the SC?

JOLYPG

I have a buzzing sound at idle, when I have ran it for about 30 mins....it seems to be a pump or something from the rear of the car....it is usually buzzes on and off at idle and a bit more when I start to move, then it seems to dissapear until I get back to idle at a stop sign.....is this the same as you are experiencing?

Cheers

Paul

GermanCars

Mercedes has issued a TSB with a description a a humming or vibration that reaches it's peak at about 1400 RPM. They recommend replacement of a damper in the ABC hydraulic system. On at least the early versions of R230's it is mounted on a valve block just behind the left front wheel behind the inner fender. You can confirm this with your local tech. The part isn't huge money but then there is labor......it would be a good idea to flush the system and change the filter to the latest version at the same time.

If you are convinced it is coming from the supercharger just take the belt off and see if it goes away.