[W126 Coupe] Low Idle - VERY low idle

[Chet Hwilka]

Could be the idle control valve, idle control module or any of the inputs to
ICM.

If I recall, with the ICV unplugged, the engine idles below 500. 
Unplug it and see if idle changes.  If it goes lower to the point of
stalling, it tells you the ICV is doing something.
It could be dirty or gummed up.

Turning the A/C on should increase the idle a bit, again telling you ICV is
doing something.

ICM takes inputs from temp sensor, throttle closed switch, A/C compress, to
name a few and adjusted the idle accordingly.

The current through the ICV should be 700-1000 ma at idle.

Chet
 

_____________________________________________
From: mbcoupes-bounces at mbcoupes.com [mailto:mbcoupes-bounces at mbcoupes.com]
On Behalf Of Henry Viveiros
Sent: Wednesday, October 10, 2007 3:25 PM
To: Mbcoupes at Mbcoupes. Com
Subject: [W126 Coupe] Low Idle - VERY low idle

My 1991 560 SEC has always idled below 500 (as the indicator reads). Once in
a while the engine starts and immediately stops. If I hold the accelerator
down a little the engine will not stop and later runs OK even at traffic
lights, etc., but the idle stays low. I can't ever remember idle above 500
rpm.

Any ideas << File: ATT00082.txt >> 
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