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.

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.

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.

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107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.

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

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.

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

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

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1992 300TE 160 kmiles

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.

Do this: Put the car in neutral or park and note if the "rough" idle or chassis vibration is there. I'm guessing it's not. Now, put the car in D with your foot on the brake. Is the vibration very evident now? I'm guessing it is. If so, change the mount on the passenger side. It has collapsed due to the direction of torque and because it is near the hot exhaust manifold. Just get one off Fastlane or eBay and swap it out. You'll be shocked.

As for the hunting idle, just clean the throttle position sensor. I think Duke gave me the suggestion about a year ago when I experienced the same thing. Spray some carb cleaner on it, then some WD40 and it will go away like magic.

These problems are common on the 300E. A few bucks for a motor mount or two (depending which side of the debate you're on) along with a few shots of carb cleaner and WD40 can practically give you a new car.

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280

Oh, one more thing. Use the search feature on this forum. There are countless posts regarding these issues.

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280

have you checked for a miss in the engine? after plugs and wires check compression if you find a miss. suspect the injector last.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

thanks for that, I'll lift the car up and and have a look at the mounts and see.

I've tried doing that earlier, but the vibration is there if its in neutrel, park or drive.

I'll try the the TPS cleaning when i get home and update you.

I've checked the plugs, and leads, i havent checked the compression. I'll try a few things first then consider the injectors.

Is there anyway i can check the injectors?

Had same problem. Vibration in idle. No vibration when accelerating. Changed 1 mount first and vibration went away. Then changed 2nd mount when I removed intake manifold. Even less vibration.
Change motor mounts

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1999 ML430 Silver 135k ml
Smoked LED taillights, Alpine in-dash DVD player, 12" sub, Pioneer components, 2 amps, 4200k HIDs, ML55 headlights, 20" rims, mirror LED blinkers

SOLD. 1996 E320 145k ml. Burgundy

SOLD but miss it everyday 1992 500sel Black
Chime buzzer mod,Alpine CD/MP3 player with stock amp,Euro headlights,S600 grill,20" rims, BEST CAR EVER!

SOLD. 1990 300E White
187k ml,smoked tails,Euro headlights,17rims,Intake,12" sub in first aid kit,alarm/autostart,buzzer mod