230TE variable idle speeds

[MartinCB]

Hi all

I am new to Mercedes and have just bought a '93 230TE. Really love the car...111K and good service history.

I have noticed that the idle speed seems to vary. On starting it can be as low as 500-600rpm but when the car has been running it soon seems to settle on about 1100 in Drive but jumps to 2000 in Neutral. Clearly this is not ideal. If I blip the throttle whilst in Neutral it settles down to about 1000. This variability seems to occur when driving as well as sometimes the throttle response seems more rapid than at other times. It suggests that something is sticking (AFM perhaps)

I would really appreciate any suggestions as to where to start looking to resolve this problem

Thanks all
Martin

 

[andy_k]

clean out the throttle body, change the spark plugs, check it's not running too rich, check the little electronic valve on the side of the throttle body is working properly - I believe it limits the revs at idle

good thread here

http://mbclub.co.uk/forums/showthread.php?t=1870

Andy

 

[MartinCB]

Thanks Andy
I'll give these suggestions a go
Cheers
Martin