MBDriver

I had this problem come up a couple times, its happening all the time now. Whenever its cold, like in the morning or at night, and I go to start (and i haven't driven it yet that day) my car I get this whirling sound. This is in addition to the normal sound that it goes through with rpms going up and leveling off. The severity of the noise has varied being really noticeable and loud to kind of faint but still clearly there if you know how its suppose to sound. As I give it more gas it goes up with the rpms. Anybody have any idea what this is/caused by? I took it to the shop a while back when it was doing this before but they couldnt find anything wrong with it and the problem just went away. It seems its back this time for good.

ejsheltra

It was a common noise coming from the clutch fans on the older W124 models when they started to go bad. It may also come from the idler belt tensioner. Check your mileage and the tensioner setting and see if it is nearing the end of its life.