You can't imagine how many of these I have fixed and yet without them in my hands I don't remember the exact caricature of each.

If the v8 KE is like the 6cyl KE then you are getting the wrong idea here. Early v8s had two wire idle controls that would race at 1800+ rpm when disconnected. This was the first idle control system on MBs. In the interest of a better "limp home" situation ( hard to drive that 1800rpm plus engine around when the system goes dead) they built valves that go to an opening just greater than that which occurs on a warm idling motor in park with no assessories turned on.

I think this is the style kE idle control the v8 has as that is how the 6cyl works.

Now for how you get low idle. This is the tricky part and it confused me for a long time. I watched the idle valve current on a 300e that was periodically dieing at intersections. I had a long wire and multimeter in the car as I drove around. For most stops the idle current dropped to 6-700ma and the car did fine. But ocassionally the current would drop to 2-300ma and the engine would idle really slow and die. The problem was the OVP and what was happening was this: The system will default to a airvalve opening that sustains say 650rpm with no current. When there is current the valve moves to this same setting if there is say 650ma. If there is 850ma the idle runs unloaded to 850rpm and at 300ma it runs 300rpms. You might have to think about that a while I sure did. The hard part to grasp is that the zero current position is faster than the 300ma current and slower than the 750ma current setting.

This is how poor solder contacts cause the slow running condition on KE cars where the same problem will cause too high idle on the early K-jet w/lambda cars. The controller wants to give 650ma and the poor connection only allows 180 through. Could be other electronic ways for this to happen but 200ma will drive the valve closed on the KE cars (6's for sure, v8s I think)

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Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician