I recently purchased a 92 MJ with the 4.0L and the AX15 with 88k for $400. I didn't think it was a bad deal. Body is a little on the dented side, one hole in the rocker and of course it has the floor board holes. I got it cheap because it sat for in a barn for a while because it wouldn't start one day. I got it off a guy that tried to fix it but never could find the problem. I really didn't care since i mostly bought it for the AX15 and transfer case to put in my 87 (bye bye BA10). But since I have it, I would like to get it running since (a) would like to know if rebuild is necessary for the AX15 and (B) easier to sell parts or what’s left of it if I have heard motor run and have driven it.
What it will do is, it will crank and you can hear a cylinder fire once in a while then suddenly it will start up and act like it will run but just when you let off the ignition it will shut off. Basically it will start but won't stay running
Did a couple of searches on here and found multiple causes for the problem. (Awesome site by the way) Here is what i know or have done
1) Fuel pump kicks on when key is turned on
2) Jumped ballast resistor didn’t help
3) Fuel pressure gauge says the pressure stays constant while cranking it over
4) Timing in correct
5) put timing light on coil wire and it will have random flashes then when starts it will flash normally but then flashes stop and motor dies.
6) Put new coil, pick-up stator, and cps and they didn’t help (I work at a parts store so I returned the pick-up stator and coil), CPS is still on since putting it one was the biggest pain in my butt I have ever had.
7) hit head off a wall a couple times
8.) looks like previous owner put plugs in it.
9) pretty sure it is electrical(?)
Any help will be greatly appreciated. Might take me a while to respond since I work most of the week end. Thank you for your time