94 YJ project that I rescued out of a farm field. This is my son's first vehicle and a project we are working on together. I have all the electrical working with the exception of getting spark. I have done the following:

rotor and cap (the rotor is pointing to the number one cap position)
Wires and plugs
emergency shut off relay replaced
crank position sensor replaced
checked the coil. Primary and secondary resistance all check out.

Am I missing something? The only thing left is the PCM. Is there a way to check the PCM without a having a fancy tool?

I'm not a mechanic however I can follow direction well.

Any help will be appreciated.

Dude, way to go will the resuce. I wish I had a answer:homer: but i'm just a newbie. But the guys on jeepsunlimted.com may be of more help! Good luck!

wires?

Plugs?

Check to make sure ALL of the fuses are good. On my 94 YJ the dome lamp fuse went out. Not sure what all years, but on a 94, the dome lamp fuse powers the ECM. No spark and no fuel. Replaced fuse and started right up.

no spark ? have you checked the fault codes ? after seeing what you have already done I'd suggest checking the crank position sensor

I've just been looking up some stuff on the pcm, but I have a different problem. Mine won't start up right away when its cold, I have to leave the ignition on for a while until I hear a relay chatter, then it fires up and runs like shit for a few minutes before smoothing out. From what I've gathered this is caused by bad capacitors in the PCM. I'll link to a more in depth guide on checking / replacing them at the bottom. Once you get the cover off of the PCM you should be able to see if any of the 3 caps are bad (buldged or leaking). Maybe we just have two different symptoms caused by the same thing or yours is worse since it was sitting for a while... but its easy to check so i figured why not.

http://www.jeepforum.com/forum/showthread.php?t=501951&highlight=cap+pcm

Check with your local Jeep dealer for a connector pin out for the pcm. Probe all of the power and ground circuits to ensure pcm has power and ground. next I would find someone with a drb2 scantool and have them hook up. Check for dtc's. That normally will lead you in the right direction. The only other thing I can think of is the cam sensor which is inside distributor. Ohm signal wires from cam and crank to the pcm. you should have 0.1ohms on both. Remember if 1 goes down it can rob sigmal from the other.
Good luck.

thanks for all that guys.. Heres a update. I got the PCM fixed. It was smoked... but still no spark.
I also cant put it into a state were it will flash the problem codes on the check engine light.

Question.. I replaced the crank pos sensor but not the cam pos sensor. would that stop spark? I think the no spark and the no self diagnostic are dif problems. I think?????

I changed the wires and plugs because it came out of a farm field and the mice had a field day eating them...

I am not real familiar with the newer models, but the older yjs had major problems with the ignition modules. There were located down on driver side inner fenderwell near the fire wall. It is a box that was about 2x3x4. Worth a shot.