mikev7

I have a prob with high idleat Cold startup. I've been reading about Benzes that idle high at startup and im getting mixed results as to the cause and fix. My car not only does it at sold start but it also does it sometimes when I park and put it in neutral. The rpm will run high then slowly decrease to normal idle. It can't be a old cat causing this if the car is at operating temp. How can I fix this?

mikev7

Bump.

mgiannetto

How high is the idle? How long does is stay high and does it drop after 30 seconds or so. More color/specificity would help.

mikev7

Here's a video.
http://www.youtube.com/watch?v=ojclBJrztVM&sns=em

03MBC32

I get the occassional high idle after running the car fully warmed up and putting it in neutral. This has been happening for years. Seem to happen more if I've had a few aggressive throttle inputs within a minute of putting the car in neutral/park. No codes set. I don't know the cause for this, but I'm not concerned and strike it up as a quirk of German engineering.

mgiannetto

That looks totally normal to me.

Mine (a C55) behaves very similarly. It's done that since new.

mikev7

it does it when fully warmed up also. sometimes ill pull up in my driveway after a drive, put it in park and...

mikev7

Bump.

Ausmbtech

For a cold start that looks perfectly normal, If it's doing it when hot and going back to P or N then you may have an issue.

I would be cleaning the throttle body and checking the crankcase breather hoses for leaks. The C32 doesn't have a air mass meter so air leaks dont show up easily but would give you symptoms like that.

JonMBZ

I had my idle lowered by a friend because of the vibration, but during a cold stat up it's perfectly normal.

pbSalvadorl

That looks totally normal to me.

Apox

Mine idles high sometimes as well. Never figured out what the deal was.