There is no idle adjustment. The screws on the throttle body are what's called "throttle plate stops" and are there to stop the movement of the throttle plate so that it doesn't wear out the ridge it fits against in the throttle body. If you mess with those, that's a mistake. If it fixes anything- the problem is the idle air control valve not the throttle stop position.
I would first remove your IAC and clean it. It's not too hard to get to on this engine. What is hard to get to is the PCV and it's vacuum line- a few people have had problems with that- but very few. It is located between the intake manifold and the engine just above the oil filter bracket. For low idle, the hose would be collapsed at idle.
Are you noticing anything electrical being reset when the engine turns off? Radio presets- etc?
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Originally Posted by the user formerly known as ZX3_Chick
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