Alright all I know somewhere out there, there's a thread similar to mine, but being that I'm on the mobile app, I can't search that well.

Here's what's going on, I figured that I had a bad pcm after my fuel pump wouldn't come on anymore, so I took my old one out and took the back panel off. Not surprisingly there was a burnt resistor so I replaced the pcm and started the jeep once with the new one in it and shut it off. Now, it won't start, except for occasionally, and even then it runs rough and misfires bad, and won't stay running even when I give it gas. I had the ignition control tested and it was good, ignition coil tested it was good, crank sensor is still reading correctly and getting the coil and control module to send spark at the right time, new plugs (ac delco 41-629), compression is good on all cylinders, injectors are firing right, it backfires into the intake on occasion when trying to crank it over, it stumbles like it wants to turn over but won't, won't even run on ether that just backfires into the intake, could a bad distributor cap or distributor assembly cause something like this to happen? It almost seems like the cylinders aren't getting a good enough spark due to buildup on the cap and rotor.

 

Did you figure out what caused resistor to go in old ecm b4 hooking up new one ?

 

Yea it was when I hooked up a pair of lights to the fuseblock when I wasn't thinking went from 55w to 100w bulbs now I have those on a relay system

 

Also, does the pcm need to be grounded it started just fine the first time while it was sitting on the floor

 

Check fuel pump pressure where id start ...seeing how it was affected by old ecm issue

 

Pressures good and everything, I'm in the process of changing the crank sensor for the hell of it

 

Pull it back out see what gives ....http://www.lunghd.com/Tech_Articles/...iagnostics.htm

 

Alright, so an update. Finally got the new crank sensor in and tried to start, ran ok (read:better than it was) for a few seconds then died when I tried to give it gas, I also swapped in a new MAP sensor for a few tries, but that didn't help much. I'm thinking I might just get a different computer and see how that goes tomorrow.

 

What were the actual results of the fuel pressure test?

 

Is there any diagnostic work going on, or are you just shotgunning parts at this Jeep?

 

^^ You're getting an intake backfire and stall on acceleration, both point to a lean condition.

The resistor in the ECM would not be affected by oversize lamps. It's probably a current limiting resistor meant to choke off excessive draw through the ECM from things like O2 sensors, injector drivers, etc. as can happen when a wiring harness shorts. Wouldn't hurt to give the wiring harnesses a good inspection.

 

This could be as simple as a poor connection at the fuel pump ballast resistor, or a resistor damaged during installation of lamps.

 

A little bit of both to be honest

That's a possibility, cause that's where I have the grounding point for the relay for the lights. If I bypass that resistor to see if it'll start ot won't hurt anything right?

 

Won't hurt a thing. YOur fuel pump MAY be a bit noisier.

 

Quick update, swapped in a new computer and it started, but misfires real bad now but I think that may be due to a intake gasket leak so that's one other thing ok going to be looking towards, but I appreciate all the advice and will probably need some more in the near future.