Can't solve high idle

[Axlerod]

I've finally gotten my car to run without throwing codes. I haven't timed the car yet, so it still pops a bit and hesitates sometimes on rev, but other than that it idles very stably.

My problem is that I can only get the car to idle at one speed. Whether it's hot or cold, it won't change speeds. If anything, the car idles higher when it's warm than when it's cold.

I've searched here and followed the FSM proceedure (unplugging TPS and AAC and setting the idle when warm via the AAC valve adjuster) to no avail.

I can sucessfully set the idle speed to anywhere between 800 and 2000rpm, but it will never change by itself. If I set it to 800, that's where it idles when it's cold, if I set it to 1500, it never goes lower when it warms up.

I've checked the AICV, in that I know it is open when cold, and when warm it still shows some vac, but when I put my finger over it it doesn't change the idle speed at all.

What am I missing?

[89'ClubK's]

Are you using a SAFC-II?

[Axlerod]

Nope, everything's stock.

For anyone confused, when I said AICV, I meant the Air Regulator (don't ask me why I called it that)