I hope people don't avoid the thread because it's an Evo, there isn't much difference at all between the 2.5 16V you got in the US and the Evo 1. The internals are slightly different, shorter stroke etc and the thing has a different FI map but the controls are basically the same. It has a lamda sensor which I don't think the early 2.3's had - at least over here in Europe. AFAIK
the 2.3 and 2.5 are so closely related most of the issues should cross. Anyway, to my update!
I removed the idle regulator and vacumn connectors and cleaned everything out. Applied 12V to the idle regulator and she opens and closes. Now holds a decent idle (950) but stayed up high on decelleration - about 2000rpm and still stalled occasionally. I put the microswitch from my 190E onto the Evo and the car returns to idle ok. It also starts first go on the key now. But I still have a high idle condition.
It now likes to sit up around 1200 rpm, occasionally fall and still stall out. Now, the car just simply refuses to go above 75 deg. So does it sound like a rich mixture and a faulty ECT sensor? Or a busted thermostat? The fans seems to run all the time with the engine which is weird. I don't know these 16V's, is that normal? Permanently engine driven? The 190e is clutch driven yeah - ?
Anyway would appreciate any input. Tomorrow I am going to check the Lamda and try and check the EHA output. But I think the temp situation may be messing up the whole works.
Finally where the heck is the OVP? Is that the seperate fuse box all on it's own in front of the main clear plastic fuse box, or is it a relay in the clear fuse box?