560 SEC Idle Adjustment Screw - Where?

[CalicoCat]

I can't find the Idle Adjustment Screw on my 1988 MBZ 560 SEC; All the
throttle bars are properly adjusted and not pulling the throttle open.
Where is the adjustment for idle speed? Thank you in advance to any
postings!

[M. Davis]

There is no adjustment for idle speed - it is controled by a small
analog computer (control unit) through an idle speed air valve. You
can adjust the mixture by way of a (iirc) 3mm hex wrench in the top of
the fuel distributor.

These affect idle speed:
- Leaks in the intake side - manifold gaskets, vacuum hoses,
diaphrams, seals, etc.
- Coolant temperature sensor
- Bad wiring, especially bad grounds
- Sticking idle control valve
- Bad news - most common problem is the expensive control unit, but
there are people who rebuild these for reasonable cost - search this
group for sources.

Diagnose first - you will run out of money before they run out of
parts. The shop manual will give you diagnostic steps. Good luck.

Mike - '82 380 SL

[CalicoCat]

Mike,

Thank you for taking the time to spell out all the great advice!

Very much appreciated,

John

[kingking]

When i try to adjust the ifle of my sel 560 ok for a few seconds and i stop it and start again totlly not starting pls help me thank you

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