Jeep XJ long fuel pump prime

kjoyner233

New member
I have a 96 xj thats been giving me fueling problems lately. When the issue first started I would have to prime the pump before starting it. Eventually weeks later I would have to let the pump prime and it would take like 50 seconds. I threw a new pump in it and the issue still occurs. What the he** is my issue?


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Have you monitored fuel pressure?
Turn the key on and listen for the pump. It should kick on and run for 3-5 sec.
You should be at std pressure.
If not key off and back on.
Check again.


When you changed the pump did it include the filter and check valve?

Also. If the vehicle sits fir a long time does it start? Another possibility is a stuck injector. If you fully depress the gas pedal it shuts off the fuel pump when starting. This will push out all the gas from the flooded cylinder. If it starts or tries to eventually start with the gas to the floor it is an injector.
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Last edited:
Have you monitored fuel pressure?
Turn the key on and listen for the pump. It should kick on and run for 3-5 sec.
You should be at std pressure.
If not key off and back on.
Check again.


When you changed the pump did it include the filter and check valve?


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As far as I’ve seen fuel pressure has been fine. The pump runs way longer than 3-5 seconds. When I changed the pump it only included the pump itself and the sock that fits on the bottom


Sent from my iPhone using Jeepz.com mobile app
 
Have you monitored fuel pressure?
Turn the key on and listen for the pump. It should kick on and run for 3-5 sec.
You should be at std pressure.
If not key off and back on.
Check again.


When you changed the pump did it include the filter and check valve?

Also. If the vehicle sits fir a long time does it start? Another possibility is a stuck injector. If you fully depress the gas pedal it shuts off the fuel pump when starting. This will push out all the gas from the flooded cylinder. If it starts or tries to eventually start with the gas to the floor it is an injector.
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After sitting it will start and occasionally the pump will only run for like 3 seconds when other times it will run for like 30... I’ll check tommorow and follow up. If it is a stuck injector then where would I go from there?


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I edited while you responded. Will it start after it sits for a ling time? Or after trying. Try to hold the gas pedal to the floor and start. If it starts with the pedal to the floor it is a stuck injector.


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I edited while you responded. Will it start after it sits for a ling time? Or after trying. Try to hold the gas pedal to the floor and start. If it starts with the pedal to the floor it is a stuck injector.


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It will always start but it’s hit or miss whether the pump will run for like 3 seconds or like 30. Im gonna try that trick tommorow and lyk how it goes


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You started with ‘this is a fuel system issue.’ Have you checked the fuel pressure and complete a leak down test?
Is it possible its something else, like, the timing is off or the crank sensor is giving issues.


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Last edited:
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