1996 W202 C280 hunting

[Will]

Hi,

A friend of mine has a low mileage (59K) but regularly used C280 automatic.

It's a 1996 pre-facelift car, straight six with the 4-speed auto box.

Idle speed is pretty low, especially from cold and it seems to hunt slightly when under load at tickover (ie, when put into forward or reverse).

Engine runs beautifully otherwise, no misfiring, smooth and clean running all the time.

Basically seems that the idle speed is a little low - where as most cars idle at say 1000RPM or so when warming up, this is ticking over at maybe 500/600 from cold.

I haven't looked at it yet (he may just take it somewhere) but I'm guessing something like the temperature sensor for cold start maybe? Maybe something like that.

Anyone got any suggestions?

Cheers,

Will

 

[gchild]

I got a 97 280 v6. My idle drops to around 500rpm after a couple of minutes. Never had a problem.

 

[reflexboy]

Same here-Mine is a pre-facelift C280, 4 Speed etc and she idles beautifully when warm at about 550 rpm, when cold slightly higher,but never as high as 1000 rpm, usually 650-850 when cold.

 

[Will]

That's roughly what I'm getting at - it doesn't idle fast enough when cold. 650-850 sounds ok to me, this is struggling around 500 in gear (forward or reverse when manouvering when cold). Causes the engine to hunt and makes it slightly jerky.

Will