I replaced the engine on my friends 92 Cherokee (4.0) and now it will randomly set the check engine light while I try to start. I have replaced the coil, wires, plugs, and the N.S.S. on the tranny as they were bad anyways. Afterwards it would try to fire off but only turn over. I finally got it to sputter/die and now it won't give the light. How do I check the ECMs power?


Madcat <img src="/forums/images/graemlins/kewl.gif" alt="" />

Just tried to start it again and the light came on. So I checked for any codes and got 12 and 55. 12 is for a disconnected battery, and 55 is the end code to tell you there aren't anymore codes. Thing is i haven't taken the battery terminals off since I finished hooking up all the wiring. Anyone have ANY ideas on this. <img src="/forums/images/graemlins/confused.gif" alt="" />



Madcat <img src="/forums/images/graemlins/kewl.gif" alt="" />

I think I would reground the body at this time.. Just to see if what I had was good enough.
Big Jim <img src="/forums/images/graemlins/pfft.gif" alt="" />

Both grounds are good, the battery ground and the body-to-valve cover are both tight.


Madcat <img src="/forums/images/graemlins/kewl.gif" alt="" />

Does it have a trailer plug? I have had a bit of dirt inside of one of several of those to drive me nuts! If it has one open it up and clean the $hit out of it.
Big Jim <img src="/forums/images/graemlins/pfft.gif" alt="" />

I don't know of a Jeep that has a computer that doesn't have the 12 code. Mine has 12-33-55 every time I check her.

Grounds are tricky.

I give ya a raised eyebrow to the grounding via the valve cover bolt.... It's fine if you have some sort of accy on the valve cover that requires ground, but the block itself, or the cyl head is a better option.

Now, the BODY ground is different than the ENGINE ground.

Another thing to poke around a bit here is the question of are you getting crank and no fire or crank, fire, no start? Both are a pain, but quite different.

So, explain a little more here....

That ground is on the back drivers side head bolt, sorry for the mix-up


It will always turn over, but sometimes it will want to start and just die. But if I try to crank it with no CEL then all it does is turn over, no spark at coil.



Madcat <img src="/forums/images/graemlins/kewl.gif" alt="" />

Is the dist. sunk in the correct place? Check it!!

Okay, sounds a little a fuel delivery issue.... computer can see things that aren't there and some things it misses because it can't see....

So, it will crank and no fire, and sometimes crank, sputter and then die?

This is getting somewhere..... explain the circumstances again, and type slowly, I'm having trouble keeping up.... I think....

Sunder, the ignition timing is dead on.


NCBBA2358, When the CEL comes on yeah it'll crank, then all of a sudden catch for like 2 seconds then kill. If the light stays on it'll repeat. If the light goes out all it does is turn over.



Madcat <img src="/forums/images/graemlins/kewl.gif" alt="" />