91 s10 stalls at idle

I have a 91 s10 4.3l 4x4 that will not run at idle speed. When I first start it(cold) it will run fine for about 1 minute then stall at that point. Once she's warm, it will stall right away unless I keep my foot on the gas. It does fine driving at a cruising speed but as soon as I hit the clutch, if I don't keep my foot on the gas, it stalls. I have replaced the following:
-PCV valve
-Spark plugs and wires
-Distributor cap and rotor
-fuel filter
-IAC valve
After all of this, it does run better, just not at idle.
If I do unplug the IAC valve, the idle is bumped up to about 2000 rpm's but she won't stall. Wrong signal being sent to the valve?
Any help would be GREATLY appreciated. Thanks.

are you unplugging it via electrical or vaccum. when you undo vaccum hose it will rev, but then you have a vaccum leak on good for rest of components that run on vaccum.
have you tested coil or fuel pressure?

timming would be a good thing to check as well.

Check timing and the EGR valve.

It will cause an idle stall.

sounds like the throttle posistion sensor

sounds like the throttle posistion sensor

How so?