Well, I guess we could have elaborated on "how" the truck will run without an IAC and not so much "will" it. Sure, it'll start and choke, but the component that regulates the air passing by the close off throttle body is not allowing the proper amount to go through thus, choking the engine. Idles will go up and down and be erratic until you open up the throttle, then all is fine....but let the throttle close and you'll choke off the motor and start the idle jump again.
You can try to spray brake cleaner in the IAC to free up the spring that is most likely gunked up with carbon. This may give you some more time until you get the new part, but may not work if the spring is jammed up too badly.
2004 Ford Ranger 4x4 XLT.....4.0 V6....4.10 rear
2" torsion key crank
235/85/16 Goodyear Duratracs
Gibson exhaust (POR20 coated)