1984 380SE 126 Idle Control Valve
 

The idle on this car is 1100 then after giving it some gas it the idle races. Putitn git in gear is a bit scary because of the idle speed.

The Idle control box looks really clean inside and appears to have no corrosion on the connectors. If I disconnect the connector from the valve nothing happens and there is no change in the idle.


I was not able to soak the valve overnight but alot of carbon came out of it when I hosed it down with carb cleaner.

It appears as if it is stuck open as I could see the slot from the side opening was not closed but I am assuming that it should be if there is no power being applied to the valve. Is this correct?

I know this subject has been talked about alot but I didn't see anything that explained how this unit operates.

The one my 190 uses is open when de-energized. I verified the mechanism was working correctly by bench testing it.

Steve

Pull the connector part way off the valve, connect a DMM to each pin and measure the voltage. I suspect you will see 0, which indicates a faulty idle control unit. Meaning that no voltage is allowing the valve to sit wide open thus max idle.

gmask,

The idle speed control module will look completely normal even if it is bad. I'm a computer engineer, and I couldn't see the bad solder joints. The cheapest fix for you is to get a radio shack soldering iron and some fine solder and get each dot of solder melted on the board with just a little fresh solder. Make sure your solder has a rosin core, as this will help it clean out the corrosion. I did a complete description on the board a while back. You might try searching for it with "solder idle speed control".

What is a DMM?

As per the previous post the valve appears to be stuck open or is it normally open when no power is applied?

Digital Multi-Meter (but analog is OK). No power is wide open, I think.