Yes, the throttle does close. And I hear the switch. Even if I move the throttle linkage a tiny bit and hear it click there is no change.

As for looking for leaks, I found a number of minor ones and repaired them. Even they did not affect the idle much.

What is most odd to me is that the idle only goes to 1500 - 2000 as soon as the engine hits operating temp.

The idle increase at temp is odd indeed.

When you did the head gasket did you have coolant in the combustion chamber? There is a posibility that burnt coolant has coated your primary O2 sensor, and it may be reading lean and thus over fueling. If this was the case, You might notice some oscillating in idle once at temp.

Still, leaning towards a vac leak, possibly the icv is plumbed backwards??

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Stable Mates:
1987 300TD 310K mi (Hans)
2008 Jeep Grand Cherokee OM642 165k mi (Benzrokee)

That's the "micro switch", which has to do with fuel shut off on overrun. There's also a switch on the rear side of the throttle valve shaft below the fuel distributor. It's connected to both the EZL and ECU via a three pin connector that is under the air cleaner on top of the inlet manifold and easy to access. One is ground and the other two are system voltage for the EZL and ECU.

I had a similar high idle problem and checking continuity at the connector showed that the switch was not working. It appears to be very difficult to remove due to its location, so my first "fix" was to thoroughly douse it with electrical cleaner. That got it working again and idle control has been normal for many years.

Duke