PCM controls the fuel pump on startup.

Thing is, you've checked all the usual and common things and we're down to the expensive stuff.
Without actually seeing your XJ, I (speaking for myself) am hesitant to tell you the PCM is shot, knowing you have some non-standard wiring and knowing there is an awful lot I don't know because I can't see it.
PCM would be the next logical thing to check, along with the power supplied to it and ground. It controls your warning lights, fuel pump.. pretty much everything you are having issues with. But it could also be something else related to the previous owner's wiring mods. I don't know, and I don't want to spend your money for you without results. That's the dilemma.

 

I'm thinking PCM also, and with what I've spent so far is not too bad. I'm only in $120 to rule out the normal plus take care of some other things. I could go with and eBay or junkyard PCM to save some coin but its probably a crapshoot guessing whether its good or not, long term or short. I do appreciate the replies I have gotten, obviously this is frustrating as it's work vehicle. The dealership shop may be my next step for at least a diagnosis.

 

Odd thing is while running, if I unplug the NSS harness it idles up then back down to normal. When I plug it back in, it drops then back up.

 

Checked voltage going to cam sensor.

When dash lights come on I've got 5v. But sometimes when they are on I don't always get any voltage. Definitely don't get any voltage when the dash lights don't come on.

Disconnected crank sensor while doing this to check it and same results with voltage going to the crank sensor.

All in all at least it's not the new crank sensor I just installed.

 

https://www.cherokeeforum.com/f59/no...cklist-155216/

 

Thanks for that. Makes me think its my ECM. The only thin I didn't do just like that list is the battery and ECM. Battery is new in Dec.

 

looking at the wiring diagram volt supply for both the cam and crank sensor come from the same pin from the PCM. Being that when I don't see those dash lights I get zero voltage to both sensors, wouldn't that point to my PCM? I've done some procedures today but the way it's been acting today everything has worked this afternoon. This morning I got up a half hour early to get it started and barely ever got a flicker from the CEL/GEN lights. So I never tried starting except for the crank just to see. I had to call in to work, but ended up going in to help but drove my daily driver. The Cherokee is just for mail delivery and I usually leave it at the post office. Came home at around 10:45 and messed with it and same thing as this morn, nothing for an hour. Then the lights started coming on and I got it fired up and drove it for 20 minutes. I then took about an hour break and used my other truck to go and came back and the lights came on and it fired every try for the last almost 3 hours. The dash lights came on every time and so did it fire. I've let it sit for 5 to 45 minutes and it worked every time.

 

Ended up being the PCM. Thanks to all who contributed any USEFUL info.