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Discussion Starter · #1 ·
3 weeks ago I filled the tank on my 98 trooper and I couldn't get it started. Towed it home thinking it was the fuel pump. Tested the pump by pulling hose off the fuel filter and it pumped gas out every time I turned the key. I changed out the fuel filter and the truck started right up. Tonight I tried to start it and its dead again. Same symptoms as before. Any ideas on what might be causing this issue?
Is it possible to have another clogged fuel filter after 2 tanks of gas? Could it be the FPR? Any ideas or suggestions would be much appreciated.
 

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Check for fuel up at the fuel rail. Test pressure off the shraider valve, should be around 40. Pumps do like to take a dump like that though. Never fails that they quit when you fill the tank.
Check the relay up in the fuse box, maybe it's bad. You can run a jumper wire up there that if the pumps good, will make it run full time so you can test the system.
 

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Discussion Starter · #3 ·
The fuel pump is working. Just like last time I pulled out the fuel filter and reinstalled it and the engine started up fine. This time though after a drove it around for a few minutes and turned it off it wouldn't restart. I did a search on how to jumper the pump but I couldn't find anything for a 98. Any ideas why the engine starts after removing and reinstalling the fuel filter?
 

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Discussion Starter · #4 ·
I swapped out the relay and it was fine. I still have to pick up a gauge to check the fuel pressure though.
 

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I might be your fuel pressure regulator going bad. Pulling the fuel filter drains off the system and forces a longer prime cycle. That might somewhat aid the fpr...to work briefly. You need to check pressure at this point to determine what's going on.
 

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Discussion Starter · #6 ·
Im going to get a tester tomorrow. If I have low or no pressure would it be the regulator thats causing the problem.Also should it read 40psi when being primed?
 

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Discussion Starter · #8 ·
Well I replaced the FPR and it started right up. Drove around for about 30 minutes and parked it. Tried to start it again and it won't start. Pulled the fuel line from the filter to check the pump and it works. Reattach the line and then try again. The trooper starts and I let it run for a few minutes then shut it off. Tried to start again and it won't start. There is no pressure at the shredder valve when I turn the key to turn on the pump. Any suggestions? Should I replace the pump to rule that out or is there something else I need to look at?
 

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I guess at this point you need to verify if the pump primes when you turn the key on. You might need to bypass the relay and see if it starts and runs. I would also do another fuel pressure test and see how long it holds for. Something might be scetchy with the pump in the tank.
 

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Discussion Starter · #10 ·
How do you bypass the relay on a 98 trooper. Ive seen the photos of older models and the connections are different than mine.
 

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Just find the relay in the fuse box.



Unplug it, make a jumper wire with to spades. Grab a test light, find the hot feed port. Then locate the output to pump terminal/port and plug it in to run the pump. Usually the two ports are parallel with each other. The two side terminals will be ground and key/ignition on off.
 

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Discussion Starter · #12 ·
I think this may be the problem as the connector that fuel pump plugs into was broken and corroded. The wires literally fell out when i touched them.
Looks like I need a new assembly unless someone knows if I can just replace that connection.
 

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Bdsomers said:
I think this may be the problem as the connector that fuel pump plugs into was broken and corroded. The wires literally fell out when i touched them.
Looks like I need a new assembly unless someone knows if I can just replace that connection.
I bought a kit from them that I use on my motorcycles and other things. Saved me TONS in the long run, maybe an option: http://www.vintageconnections.com/
 

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Discussion Starter · #14 ·
I was able to salvage the connector and replaced the wiring along with fuel pump and everything works fine. I am going to order one of those connection kits. Between atv's and motorcycles I'm always having to replace or rewire something. Thanks for all your help.
 
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