2000 TJ 4.0 fuel pump issues

Fixins13

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Sep 20, 2021
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MA
I'm looking to buy a TJ project. I've had 6 YJs a couple XJs and a ZJ so I know a little about Jeeps. A guy near me is selling a 2000 4.0 as a non-runner at a reasonable price. It's been for sale a long time so I think there's some room to negotiate. He has shown me a receipt for a shop putting in a fuel pump. Now he says it gets no fuel and he's tested it at the connector and there's no power to the pump. Assuming the shop did replace the fuel pump and assuming that new pump does work that leaves me with some electrical problems. Is it the fuel pump fuse/relay or a bad ground going to the pump? A bad or flaky CPS? Here's my thoughts so long as it has spark, I'll hot wire the pump on. Any extra fuel will simply cycle back into the tank and running the pump constantly for 2 hours home while probably isn't awesome for it, isn't going to murder it on the spot. What I'd like to do is make up a temporary feed for the fuel pump. I'd run a relay to the parking lights with a fuse so I can turn it off and then run wires under it back to the pump. Does anyone know if anyone makes a fuel-pump pig-tail so I don't have to chop the stock wires to get this done? Yes, I understand it's dangerous and if I flip it over it's going to pour raw gas everywhere. I understand the risks. This is a short-term fix to get the Jeep home where I can take out all this butchery and figure out why the Jeep isn't giving the fuel pump power/ground. I'm not looking to diagnose a Jeep in someone's yard but taking the back of the tank down enough to unplug a plug a put in a different one, I can accomplish in the street if I have to. Thanks for any insight.
 
Since the previous owner showed proof that the fuel pump was replaced and there is no power to the connector at the fuel pump; have you checked the function of the fuel pump and automatic shut down relays ?
Fuse 12 (10A) in the fuse block behind the glove compartment and Fuse 23 (20A) in the PDC in the engine compartment power up the fuel pump circuits.

There is a PDF of the FSM for your year TJ that can be downloaded to assist you in troubleshooting. Section 8W has pin outs, wire gauge and colors and fuse information for the different power circuits; pages 8W-30-2&3 have the wiring to assist you.

https://wranglertjforum.com/threads...ice-manuals-fsm-technical-documentation.4618/
 
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I have not done any hands-on trouble shooting. My fear is I go to where the Jeep is (90 minutes away), monkey around with it, get it running and then the seller says "oh, it's running? The price just went up $1,000." I was going to crank it, having done nothing but pull a plug wire to check for spark. If there's spark, that eliminates the CPS. Then I'll spray some starting fluid down the throttle body. If she runs on the ether, I make a deal for the Jeep. Once it's mine but still far away from home, maybe I'll check the relays and fuses but really, I just want to get it home in the least destructive way possible. Once I'm home I can take my time, check voltages, grounds and wire continuity. I once bought a "non-running," XJ that had nothing more wrong with it than a loose battery cable. I fixed it with my pocket knife in the seller's driveway. Seller was MAD.
 
U-Haul two wheel dollies you can put the front wheels on used to not be very expensive for a day if that might be an option if it seems to crank over and build oil pressure. You might have a deal.
 
U-Haul two wheel dollies you can put the front wheels on used to not be very expensive for a day if that might be an option if it seems to crank over and build oil pressure. You might have a deal.
When I moved from CA to FL several people mentioned NOT using a dolly because towing with a trailer is much more controllable for the towing vehicle.
I would recommend a trailer instead of the two wheel dolly; too many horror stories about towing with a dolly and losing control.
 
A UHaul might not be a bad idea. I've used a couple fly-by-night tow services on the bleeding edge of legitimate/legal in the past who I might see if I can find again. Might also just slap my plates on it and call AAA and say it's broken and needs to be towed home. An old scam but a good one. Haven't used my membership for years but I keep paying for it. Now may be the time to run up a tab on AAA's dime.
 
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Someone beat me to it. If it was someone on here, best of luck and long may you run. Maybe the next one I'll be able to drive home without fear of pouring raw gas on an electrical fire? Thanks for the help in any case. Fall Jeeping is my favorite so I better look sharp!