1990 4.0 will start and stalls after about 20 sec.

as the title says, and I have replaced the fuel pump, map sensor, tps, iac, cap and rotor, plugs, wires tried jumping the resistor and that changes nothing - it starts right up and it wont really take and throttle or it spits and spuuters and stalls or if you just start it and dont touch the gas pedal it will eventually spit and sputter and stall - after it stalls it still has plenty of fuel pressure in the rail when you depress the schrader valve i'm really at a loss here - it stalled while driving and had it towed and this is where im at - a bunch of new parts and nothing PLEASE help me
thanks

I would check fuel pressure at the rail to make sure the fuel pressure regulator is OK. If good, I would likely swap in a new crankshaft position sensor with those symptoms. The tps and iac were possibilities. I wouldn't think plugs, rotor, cap, or map sensor would totally kill the engine, just make it run bad.

I would test the volts from the CPS also. that sounds like the culprit. also, if you havent already, replace the fuel filter. when I did my fuel pump, the filter was so bad that you couldn't even blow through it.

ok, yeah I have a new fuel filter but I will get a CPS and do both of them and if there are any other suggestions I will try those too, thanks alot guys

Sounds more like your EGR valve stuck open then anything else....

well, I put the new crank sensor and fuel filter in - seems the previous owner (he had it 17 years since new then I bought it) spliced the crank sensor wires for some reason so I was glad to replace it but the filter was pretty clogged, well all said and done it didnt change anything so I still had the resistor jumped but I had it jumped with a test light that way I could see if current was flowing through it or not and I had a thought that maybe the resistance in the light bulb was making it so there wasnt enough power to my pump and viola that was it it runs good now - so after about 8 new parts it is all ready to go wheelin again - so let this be a lesson to all who are reading this and thanks to the rest of you for your help -- actually I am kind of glad to have a bunch of new parts on this thing - and I can keep the old ones since they werent the problem anyway

Yes, a light bulb in series in a circuit acts as a current limiting device. If you have a 12 volt circuit and put a 12 watt bulb in series (probably a fair guess at the rating of a circuit tester bulb) , then it will only allow 1 amp to flow (ohms law). A fuel pump is a fairly high current device (I would guess 3 - 5 amps), so it wouldn't run right. I collect antique radios and use a 100 watt light bulb in series when powering up old radios for the first time to limit the current and protect their power transformer in case of a short.

Glad you got it fixed.

yeah, I should have never dropped that electronics class in votech school