E300D: High idle on cold mornings problem - PeachParts Mercedes-Benz Forum

bhehmann · #1 11-02-2010, 09:52 AM

Good morning all.

I recently moved from Florida to Texas where it becomes a lot colder than what my Benz is used to.

When I start up in the mornings, it idles at 1200 - 1500 rpm and it won't come down until it's reached normal temp (80), and that takes about 20 minutes. The outside temperature has been in the 50's, hardly cold, what's going to happen when winter sets in?

How do I resolve this problem?

Thanks in advance,

michakaveli · #2 11-02-2010, 10:39 AM

Subscribed. Interesting quandry....

freesoul · #3 11-02-2010, 10:44 AM

I know my Ford diesel does this to prevent the injectors from clogging. Never noticed it on my E300d

Olivier · #4 11-02-2010, 11:15 AM

Would that not be the accelerator cable too tight or the regulator that is not working properly?

jubjub · #5 11-02-2010, 11:24 AM

I seem to remember having this problem on our 95'. If I recall correctly, it was a stuck linkage near the injection pump. I'd pop off all the ball joints and lube them up

bhehmann · #6 11-02-2010, 11:29 AM

Quote:

Originally Posted by jubjub

I seem to remember having this problem on our 95'. If I recall correctly, it was a stuck linkage near the injection pump. I'd pop off all the ball joints and lube them up

I'll look at those, but the problem is evident only when the car is still cold.

jubjub · #7 11-02-2010, 05:50 PM

yep, same problem I had. I think it was the linkage that went straight down beside the IP. I guess when the engine warmed up, it freed up enough to move back to the normal position. May not be your problem, but it worth a check

iceman805 · #8 11-02-2010, 06:33 PM

Add another vote for the linkage...same thing happened on my 95 E300D.

markinsta · #9 11-04-2010, 02:38 PM

1995 E300D

This was a problem I have had for last 5 years. Slowly has gotten worse each winter-and I live in Florida. It got so bad last year that the idle would be stuck on 3000 or more! And warming up you have to be there as it can be 1500 and then race up high on its own.

Was told it was a sensor all the way up to drilling two holes on the metal throttle on top and attaching a spring to keep the throttle pulled tight. This does not work as it reeks havoc with the temperature gauge. Another Mercedes Expert told me to buy a block heater. "I didn't need one before" gives no answer...

I have come to think it is the arm that goes down below the manifold behind and beside the IP. I think this goes down about 8 inches and there is a spring down there I see with a flash light.

This spring pulls the arm up which decreases the throttle on top.

I went to Mercedes dealer and purchased a new spring (L/051138v991207). I will replace when I can get in there as I see if this bar pushes up tighter would solve the problem.

I have no way to take the manifold off myself

which I think is required to clean down there properly?

I have to solve this before cold weather comes...

All in all this car is great. Bullet proof!

iceman805 · #10 11-04-2010, 05:05 PM

Quote:

Originally Posted by markinsta

1995 E300D
I have no way to take the manifold off myself

which I think is required to clean down there properly?

The first thing I did when I got my E300D was to take the manifold off give it a hot bath at the local machine shop.

See this thread if you are interested...unfortunately some links are bad now.
http://tinyurl.com/2epohpa

JimmyL · #11 11-04-2010, 08:40 PM

I've had this problem with my '95 and it has been two different linkages.
First, the one that goes down to the IP as stated above was one, and the one on top of valve cover that goes to the EGR flapper {Which has now been removed since EGR is bypassed and flapper is secured open}.
Mine idles fine but won't accelerate when cold, but that is another thread completely.....

markinsta · #12 11-04-2010, 09:43 PM

What product to use to lube and clean?

Maybe I take to machine shop to get manifold cleaned and while that is done I can clean linkage and replace the spring.

Can I do this without removing the manifold?

1995 E300D

Thanks to all

alphadeltaromeo · #13 11-05-2010, 12:56 PM

Quote:

Originally Posted by jubjub

I seem to remember having this problem on our 95'. If I recall correctly, it was a stuck linkage near the injection pump. I'd pop off all the ball joints and lube them up

Exact same solution...and mine was specifically the linkage to the cruise control unit. ATF on the linkage and you're golden