560 SEC Idle Adjustment Screw - Where?

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!
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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
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Mike,
Thank you for taking the time to spell out all the great advice!
Very much appreciated,
John
M. Davis wrote:

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