So i got a chance to tinker with my friends 2.3l CGT. It has an idle problem that when its been warmed up, after you let off the gas it will want to stall and then the idle will smooth out. So i pulled the ISV out and cleaned it, the valve was moving freely. Then I turned the ignition on with the ISV pluged in and I got nothing. Correct me if im wrong, but isint the valve supposed to be opening and closeing? The one on my 4kq does. Then I plugged the air hoses back in to the ISV and started the car. I then proceded to unplug the electrical connectors, figgureing that it would cause the car to idle incorectly or even stall comepletely, and nothing happened. I am assumeing that the ISV is bad. Am I wrong? Could it be anything else? There are no vac leaks that i could find. Any BTDT on a 2.3l like this? Thanks!!!!

I think you can find the details on 20v.org.

i have the same problem on my dads car,93 audi 90 (500e in south african terms),we eventually started the car isolated throttle body,isv,water temp,fuel distriburor idle ,connectors.set the engine to run 2000 rpm
static tuned it with timing light to 15°,and done fuel air mix. revvs wet to 1200 connected every thing back except isv. now she idles +-1000
rpm no stalling..tested if ecu was in limp home mode. not in limp home..i think there is a problem with these isv & ecu`s reaction time for isv..