OK when I get a chance I definitely will, right now the truck is sitting in my friend's driveway... I'm gonna save that link you sent to me and show it to my friend that's been helping me when he feels better... Right now he's gonna be bedridden for a week because he caught whatever his son had, some kind of flu like crap... Today I replaced the plugs and put the pedal to the floor exactly like you said, I doubt the engine is flooded anymore but it still won't start. Tested spark today and it's weak. Was smelling a lot of gas when trying to start it so I'm still not suspecting a fuel issue here. I bought new plug wires today that I'm gonna install, even though the old ones are only a few years old and look alright. Better to work with new parts that I know are gonna work rather than play guessing games with old ones... Also just for ****s and giggles I ordered a new ballast resistor being that they're cheap enough anyway... I guess we'll see what that does when I get it in a few days or so. The negative battery cable is grounded to the inner passenger fender and it looked fine to me. I researched into the BCM more and it's for sure that the 91 XJ does not have one. All I know right now is that my truck is defying logic and with the other half of this repair operation currently being down and out, this thing may have to sit for a while yet...

 

I haven't thought to check fuel pressure yet being that starting fluid didn't even help this thing to start, but it's gonna be one of those things that I'm going to be checking for just in case when my friend is feeling better again and he can dig his gauge out of his garage... It's somewhere in his world of tools haha. Being that I'm getting a spark (even if it's a weak one), I know that the aftermarket sensor is working fine for the time being...

 

Yeah I figured that out for myself after conducting further research last night to find that my Jeep doesn't have a BCM

 

You can jumper the wires from the ballast resistor together to test.

 

Yeah that's what my friend had done which is why I said in my original post that we eliminated the ballast resistor as being the issue. However, I was talking to a customer today and when I looked up his warranty info, I realized that he had the same last name as my friend (and it's not a common last name) and realized that this was his brother I was talking to and just meeting LOL... He told me that the truck wouldn't run without it at all, even with jumper wires... Which is what prompted me to order one anyway, and even if he gave me wrong info, at 13 bucks, it's better to be working with a new part than to play guessing games with an old one.

 

This is probably the best place to start, $7.95 for a FSM:
http://www.pacificcoastmanuals.com/1...ce_manual.html

 

Could you describe how you are testing for spark?


-I would test for fuel pressure (very easy) and rules out a lot of things it could be.
-I would check all the fuses in the fuse panel to see if something is out
-I would swap the fuel pump relay with another relay known good. If I worked at Autozone I would certainly try this!!!
-I would clean the relay prongs with a wire brush to make them happy and also use some electric contact cleaner on the sockets
-I would check the AC voltage on the CPS while someone cranks it. You need a voltmeter set to low AC volts (0-1V AC range). CPS should be in the 0.3 - 0.8 range. If too low, you won't get it to run.
-Any chance you got bad gas? I think it would still start on starting fluid though.


Keep us posted. It will be something simple most likely so just keep checking for basic things like fuel, spark, relay, electrical connection/ground etc.

 

Probably not the issue but something to check. There should also be a ground wire from the negative battery cable clamp to the block above the starter if I remember correctly.

 

Hopefully you don't run the starter too long at a time, or you may have another problem from over heating it etc...
Did the new distributor have a new camshaft position sensor with it ? Did the cap & rotor come with it ?
Are you checking spark directly from the coil wire ?

It's always possible that some wiring or connector(s) were disturbed while replacing other parts etc, & trying to get it to start. Auto-shutdown relay is in the mix also I believe...


Just some items to think about...

 

well ?

 

I think so too. I'm not sure about the '91-that's the first year after RENIX. I assume there's still a dipstick ground bolt on the block for the negative wire to go too.

 

My Jeep doesn't have a cam sensor... It came with the new cap and rotor, yes. We checked spark from the ignition coil itself and I remember it being good, not sure though, it's been over a week since I've done much with this thing, between working, errands, New Year's Eve, and waiting for my friend to get over his flu. He's almost ok now, after the weekend we're gonna get back to working on it. Tomorrow I'm installing the new plug wires and ballast resistor and seeing how that turns out. It's also tough to get to my friend's place to work on this thing when he's too sick to give me a ride and my brother's busy with his stuff... If the auto shutdown relay went bad, wouldn't I have a no spark condition?

 

We're testing for spark by sticking a screwdriver into the end of the plug wire and holding it just over the metal part of the AC compressor. When work resumes on this thing after the weekend I'm gonna check for everything that you said. I really doubt that it would be bad gas, and you're right, even if it was, the engine would take right off regardless with the starting fluid if the fuel was the issue. I filled up my tank completely and drove around for a week with no issue and when it stopped running it was down to half a tank.

 

An engine needs three things: fuel, air, spark. You are getting fuel and spark so check for air.

The skinny pedal isn't for fuel, its for air (butterfly valve). When you aren't pressing the pedal, the computer opens the Idle Air Controller valve on the throttle to let air in. The computer uses the Manifold Air Temperature sensor to measure temperature and the Manifold Air Pressure sensor to measure pressure, together they let the computer calculate air density. The computer already knows air volume (combustion chamber) so density is all it needs to guesstimate how much fuel is needed for good burn. Finally the O2 sensor gives it feedback. All of these should be tested per factory spec.

Also, if you were messing with the thermostat then you might have damaged the coolant sensor. That is used by the computer to tell when engine is warmed up and can make it run really rich, which is another way to throw off the air/fuel balance (in addition to any other problems).

 

So today the plug wires and the ballast resistor were replaced... We're getting a blue spark now which is much better than what we started out with a few weeks ago, but the engine is still not even attempting to start. Next on the list is going to be a compression check and a fuel pressure check, although I smell a lot of gas when trying to start this thing so I really am doubting a fuel issue. I finally also got the pictures of my engine block as well and I do not see a C101 connector at all, so as soon as Chrysler took over, they must've removed them from production right away.