gdinerio

First I just want to start of by saying this site has been a great resource to me and thank everyone who post as it really helps diagnose possible problems before they arise so a big thanks to everyone for that.

Vehicle: 2006 E350 4Matic 65k miles (Oil just changed at 64k)

The past two morning I have been in a rush and have noticed that when starting the car and just just driving off after about a minute or so of "warm up" when I stop at say a traffic light and the car sits for like 2 to 3 minutes the idle gets shaky (almost along the lines of a misfire shake), once I begin to accelerate the car will make a rough change into the next gear. Now I normally let the car heat up as I live in New Jersey and the past few morning have been 25 to 28 degrees, so my question is should I chalk this up as cold start, car needs to warm up, as after it does get warm its smooth sailing again. Or could this be a sign of something going wrong, as I am not seeing any check engine lights or anything but am concerned and would rather head this off than wait for it to be a full blown problem. Any help you guys can provide would be greatly appreciated. Thanks in advance.

lkchris

Shouldn't be happening.

SZMB

My guess is that the idle control valve and the throttle body need cleaning. The throttle may not open all the way (or sticky) at cold. Rough idle at cold is a common problem to many old or high mileage cars.

nstanford99

my 04 500 with 58k does this sometimes to whenever i wait in traffic in the morning, but i start my car and get in it 10 mins later, but it doesnt happen that often.

AmazinglySmooth

Is this easy to do?

SZMB

Not that easy on the E or C class. The throttle body & ICV are mounted on the back of the engine, after the mass air sensor. There's not much room to work with. I haven't done this on the E class, but did it on the 1999 C280. It took me about 2 hrs to remove the throttle body and then cleaned it with carbureator cleaner. I couldn't find a good angle where you can just spray the carbureator to the throttle body and ICV, that's why I had to removed them to get a good cleaning.
However, this job is super easy on the BMW 3 or 5 series, where the throttle body and ICV are mounted on the side and you don't have to remove them from the engine. It's a 30min job on the bimmer.

gdinerio

SZMB, I had the throttle body thoroughly cleaned and I could immediately tell the difference when I turned the key. The car started up very smoothly, and gear changes have been just as smooth. The true test will be on a cold start again, but so far this seems to have done the trick.

AmazinglySmooth

Would an "engine cleaner" help with this?