1990 300E driving me up the wall

[aus124]

I just bought a 300E 124 1990 model with 103000kms on the clock, its a very nice car only thing is that on idle it vibrates the whole car (meduim vibration).

I tried everything that i read on the forums:

-adjusting the EHA screw (it seemed ok when i first put everything together but after that 2 minutes later it went back to the usual vibration)

- Adjusting the Mixture tried doing that in conjuction with the EHA adjustment but still no go ( did unitl i got around the 4V between pin 2 and 3).

- check all the vacuum lines everything seems ok.

- I tried taking off the ICV and cleaned it with carb cleaner it looked clean but ithought what the hell (might as well).

THe engine mounts seems ok.

[DieselGuy]

I would give those engine mounts a second look. I would also check to make sure the mounting bolts for them are tight. I have a W124 400E and the bottom bolt of one of the mounts came loose and vibrated a lot at idle especially when turning the steering wheel. Tightening the bolt smoothened it, but replacing both mounts made the engine idle imperceptible.

[Greg in Oz]

Originally Posted by aus124

THe engine mounts seems ok.

You need to be absolutely sure the engine mounts are OK. Those who have experienced the effects of bad mounts on W124s and similar models always stress just how much effect mounts have.

With KE injection you also need to be sure of good injectors. Many argue that new injectors (not that expensive) are well worth the expenditure and effort.

Fortunately I have not had rough idle problems to deal with, but these issues stick in my mind from many posts I have read. If and when I have any such problems they will be areas I will investigate.

[aus124]

the reason why i think its not the mounts cause upon acceleration or reviing the engine the vibration goes away.

The rough idle feels like there is a bit of a miss or something but i cant find the culprit

[aus124]

also after i cleaned the ICV, I started the engine without the icv being connected, while the engine was running i connected the ICV and the engine stalled.

after all is connected sometimes the idle will hunt, whilst being rough.

[aus124]

One more thing, when i first got the car the car was stalling so the mechanic replaced one of the 2 fuel pumps, I'm thinking maybe the other pump is on the way or faulty

[MrCjames]

Check your engine mounts for adequate clearance: the distance between the vehicles frame and the aluminum exterior of the mount ideally is 10mm or greater. Any lower than 10mm you will feel the engine running.

[Bruno_300TE]

Originally Posted by aus124

the reason why i think its not the mounts cause upon acceleration or reviing the engine the vibration goes away.

I do not think that this is a valid conclusion. It could still be the mounts IMO. Mounts are assessed by the clearance between chassis and mounts: the older they are, the more they collapse, the less clearance there is.
Good luck, Bruno