Calling all re-enforcements!

I have a 90' Cherokee which I have owned since high school. I have replaced alot of parts on it only because I really love the dam thing, but this problem has got me stumped, maybe you guys can help.

1. The problem: starts when cold after a few spins, stalls out, after a few minutes, will start again after a few more minutes and stall again. Oil pressure is about 30lbs. at idle speed, voltage good.

2. Parts replacement history: CPS, MAP, O2S, TPS, ECM, coil, distribitor, all replaced 2 years ago when I had a similiar problem, turned out to be the ignition switch on the column.

3. I have replaced the following parts in the past week: new head gasket, seals, 2 O.E.M. injectors, fuel pump assembly kit, ecm, coil, distributor, rotor, wires, ingition switch on column, radiator, coolant reservoir, thermastat, and thats about it.

4. What I have checked: battery cables are fairly new and in good shape, good ground, replaced all the above parts, allowed computer to learn new positions by disconnecting power until I finished my breakfast, checked all vacumn lines for clogs, cracks and leaks, replaced dry rotted lines with new , possible lines in wrong place, I used the Haynes 84'-00 Jeep repair manual for vacumn diagram. No clogs, some oil in filter but thats a Jeep thing.

Thats about all the info I can give, so look it over and give me your best guess or even better tell me what to do next, I do yahoo so look me up if you wanna chat about it.

Thanks alot guy and gals.
May the Jeep Gods be with you ( cause you will need them at some point)

Cupit
90' XJ 4x4

Can you keep it running using some throttle? What about starting when it's hot?

Check the IAC and EGR.

thanks for your reply, I got it fixed after reading about another 89 Jeep on this site, a reply said check the crankshaft Positioning Sensor (CPS).

So I did. As I said before I replaced the headgasket, radiator and cooling resevoir to solve a overheating problem, mostly a blown head gasket but I love my Jeep so i changed everything including thermostat.

So I checked out the CPS and what did I see. When I bolted on the header I accidentally got the CPS wire in between the head and header, so it got fried.

So I replaced it, started it and its back on the road.

Thanks to this site and its members I shall ride again.

Good catch. Thanks for the reply.