There is an ilde mod that has been done to many of the Mercedes that I have worked on. I do know that it was printed, but I don't know if it was a TSB or an internal repair for the dealers.
The mod will allow for the idle to remain at 750 when the engine is in gear. Now it drops by 100 when in gear.
1992 500E (very soon I hope
1981 280GE SWB
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