190e 2.3 superfast idle
 

The idle on my 1992 190e 2.3, suddenly, has started to run very
fast (2000 to 2500RPM). So far I have removed the power connector to idle control valve. Doing this had no effect. I also checked the voltage to the ICV and it was OK.

Any thoughts on what I should check next would be greatly
appreciated.

Thanks

Lee

The engine can't run without air. Properly, this should arrive via the throttle valve or the idle air valve, mainly. This way, it will also be metered via the fuel distributor, and the proper mixture will happen. If there is an air 'leak' elsewhere, metering will be incorrect, but the engine will usually still run, and faster. If the throttle is closing all the way and the idle air valve is not stuck open, then check the air hose plumbing.

Steve