87 ranger wont rev past2 rpm after motor swap

i took a 2.9l bronco motor and replaced my truck motor with it. i'm pretty sure the timming is exact and that distributor cap and rotor are good wires are on correctly. but heres what is happening it starts up fine and idles descent put wont rev past 2 1/2 rpm and seems like one of the wires is shot or backwards but that isn't the case. also after it heats up a little bit it stalls out. basically it seems like one of the wires are wrong, but they aren't. also the oil light is on. what could it be.PLEASE HELP

i took a 2.9l bronco motor and replaced my truck motor with it. i'm pretty sure the timming is exact and that distributor cap and rotor are good wires are on correctly. but heres what is happening it starts up fine and idles descent put wont rev past 2 1/2 rpm and seems like one of the wires is shot or backwards but that isn't the case. also after it heats up a little bit it stalls out. basically it seems like one of the wires are wrong, but they aren't. also the oil light is on. what could it be.PLEASE HELP

Wow, that could be a whole host of problems. I think you may have a damaged main wiring harness, but I am not sure. The oil light is not low pressure, but actual low oil in the pan. Check the wiring and the level of the oil. The sender is located on the side of the oil pan itself.

Could the SPOUT have been removed and not replaced? This will cause the timing not advance or retard.

First thing I do before I even attempt to start an engine I've rebuilt or replaced is to check the computer for KOEO codes.
http://www.troublecodes.net/Ford

Is the engine getting unusually hot? IAC sometimes causes symptoms as you describe, but I would run the codes first if I were you. :)

Sounds like the timing needs advanced, or it's running too lean (check plugs), or there's not enough fuel pressure, or the ECC is not advancing/retarding the spark correctly. Usually running the codes is a good first place to start :).

Good Luck,
Pete