Payson

Hi guys :

I wanted to ask you about a problem I have that is driving me crazy :
The other day I went to the Mechanic to change the belt tensioner, belt and belt suspension; & also I changed the engine mounts (silemblocks) of the engine and the one of the transmission.
I did this to try and fix the rough idling I had in my car that was literally moving my body at idle. The problem is we have changed all this parts and idling is high more confortable, but you still notice frequent vibrations in your seat and the RPM needle varies a bit if you look closely.
I would appreciate a lot your help with this problem if anybody could help.

Thanks a lot
Payson

Parshman

might be a fuel problem, or air MAS problem

MediumKahuna

Check your EGR system (valve, pipe) and check for vacuum leaks in general. Lots about it in here. Search

Bigpete123

the mercedesshop forums also has tons of info on this problem.

Unfortunately, this issue plagues all w124's at some point and there are many many potential causes. I've had mechanics trying to track the source of this problem down for me for years with no success.

neanderthal

shoulda done the water pump while you had all that stuff out. especially if you dont know its history.

anyway, the vibrations can be caused by so many things that its hard to pinpoint exactly where to look next without knowing what has been done.

if its really bothering you, id say get the transmission mount changed too, get a tuneup, get your tranny oil and filter changed.

NorCal124

Are you sure you have proper plugs in the car. If you've installed platinum plugs that can cause rough idling. MBs (unless they're the newer ones) require standard copper plugs.