I have a 94 k1500 thats idling to low (below 400 rpms) I was sitting at a red light and thought it was dead until I tapped the gas. When the engine is cold it does just fine but when its warm it drops pretty low. When I give it a little gas it tries to stall but if I give it alot of gas it revs fine but then when I let off it and the idle starts to get back below 1000 rpms it tries to stall again but doesnt. I dont know if this has anything to do with it but it was pretty low on gas when this was going on. The motor that used to be in the truck did the same thing, and the only thing that came off of it is the throttle body.