So my jeep is once again dead on the side of the road. I had gotten it running last night so I took it to work today. Bad choice. Going through an intersection it cut out. I rolled to a nearby parking lot and started to try and figure it out. Well the original problem started Sunday. Jeep cut off so I started to replace things. Coil, fuel pump, CPS, and all relays and fuses associated. Still nothing. My dad then has me jump the starter with a screwdriver and whala! It runs!

I thought I had it isolated. All I had to do was jump the starter and it was good. It was good all the way til 2pm this afternoon where it decided that I had gone far enough. First I tried jumping the starter, all it would do is crank. Next I check fuel, no pressure. Darn so I crawl under and look at my new fuel pump. It's not kicking on. So I hot wire it( I checked what wires were pos and neg first) nothing. For kicks I test my old pump. It works! So I swap them out.

Alight now I have my old pump hot wired with a fuse and it's pumping! Woooo! I jump the starter and it runs! I let it idle then rev it a few times. I think it's good so the gent giving me a jump disconnects the jumper cables and it dies! We hook everything back up and now the fuel pump isn't pumping. The fuse isn't blown and my wiring is good. So now what? I'm at a loss guys.

Also with a test light I've checked the following:
Ignition switch- good
Solenoid wire plug under fuse box- no power on box side.
All fuses

Any ideas would help.

 

see if your auto shutdown relay is bad...

 

when you start jumping electrical components, you start sending more current through things than was originally intended... start with your fuses and relays, then you may be chasing wires for awhile. this had some hack wiring done on it before?

Yes, I read you said your wiring was good... but, sorry bro, it isn't. This is an electrical problem. Thinking you already knew that though.

 

I swapped it. But I will replace it

 

Yea, lol it looks good. I went through all the fuses and swapped the relays. And no hack wiring. Completely stock 93 xj sport 2wd ( I just have a lift and some bolt on/ cut off accessories, nothing wired in other than an aftermarket radio.

 

Can't be positive on your 93 but my 90 has a ceramic resistor for the fuel pump forward on the left hand inner fender. The front gets batt power and the rear goes, I think straight to the pump. I gather Jeep knocked the pump voltage down to 9-10 because people complained about the noise. Anyway you can see about power there probably.

 

not real sure on 93, but my 89 had the positive and ground cables from battery ran together in same plastic protector...guess where there was a short. may be worth a looksie, the little hot wire from battery to relays, ignition and all that junk could be deteriated like a problem i once had on my 88

 

ahhh... come to think about it... I've seen alot of those ceramic resistors broken...

 

well i bypassed the ceramic resistor and got it running. ( only by jumping the starter) but now after its been driving for about 15 min it starts to back fire into the intake and loose power. feathering the petal only buys me 5 or so mins before it dies out. but when it dies i restart it and its good for another 15. ideas?

 

I had a similar problem on my 96. if you can start it with a screw driver, than you might be getting voltage but not amperage from the wire. if there is a bad connection or corrosion, you only need one strand of wire to get the desired voltage but won't get the correct amps to do whatever. in my case it was my battery terminals that I had to temporarily bypass until I replaced them. and it was cutting out randomly as well. it took me 3 stops and a couple miles of coasting to make it 20 miles to the shop.

 

So you replaced just the connectors or all the cables? Did yours back fire at all?

 

Hey cool, that's a start. (ha ha). Not likely but a supper easy check. My 90 was doing that, backfiring and funny on the throttle. Actually blew a mouse nest in the air cleaner out the front grille. I drove through the confetti. No sign of the mouse. I fear the worst.

Took me forever to figure it out. My injector wires where shorting out underneath where I couldn't see, where they come up and back toward the injectors. That black ribbed deal has a slit and some wires where out a bit on the bottom. It would only do it after the heat shield expanded from heat, than be fine when it cooled off. In the year+ it took me to figure that out all I bought was filters plugs wires, cap&rotor

 

Where is this heat shield you speak of? As far as I know I have no heat shields.

 

You may not have one but you can still check that the wires aren't rubbing or touching somewhere. I can't tell you what a bicch this was, and right under my nose all that time! The shield would expand, just a tad, then sometimes, not always cause all sorts of mayhem.

 

Well I went and looked and the wires coming up right there are melted! Not crazy but I'm assuming it's a problem. I'll be adding it to my to do list.