I recently bot a 1993 190E 2.6 w/85K mi.
It idles at 2,000 rpm. Several techs looked at it and have different opinionsabout the computer, possible vacuum leak, idle control valve, etc. I think I have eliminated those possibilities by subbing parts from others cars geeting the same results.
Yesterday I unplugged the electrical connector to the idle control valve while the engine was running, thus breaking the circuit, then reconnecting. It then idles and runs perfectly until shut off and restarted. When restarted, it goes back to idling at 2000 rpm and maintains that state until briefly unplugging the idle control valve again.
Is this a problem that can only be traced to the Overload Protection Relay or perhaps the computer?
Any other thoughts? Thanks.