Renix fuel pressure issues
02-02-2019, 12:46 PM
#1
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Year: 1989
Model: Cherokee
Engine: 4.0L
Renix fuel pressure issues
89 XJ... 95,000 miles... I put a guage on my Schrader valve...
Key in on position the number jumps to almost 30 and then falls back to zero.
Engine running I have ~15 psi. When I unhook the vacuum from the pressure regulator there is no change.
Am I looking at a bad pump, regulator, or both?
Key in on position the number jumps to almost 30 and then falls back to zero.
Engine running I have ~15 psi. When I unhook the vacuum from the pressure regulator there is no change.
Am I looking at a bad pump, regulator, or both?
02-02-2019, 01:55 PM
#2
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Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
That has an exterior filter mounted just forward and left of the tank. In your shoes I'd ether check and back-flush that, or change it, then continue troubleshooting. A Renix regulator failing isn't reported much. The check valve in the pump or leaking injectors is another issue.
Last edited by DFlintstone; 02-02-2019 at 01:58 PM.
02-03-2019, 08:44 AM
#3
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Year: 1989
Model: Cherokee
Engine: 4.0L
Brand new Napa Gold fuel filter last week and the injectors are 4 holes bought from a forum member. I reckon I'll order a pump to start and see if I can get those numbers up.
02-06-2019, 04:27 PM
#4
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Year: 1989
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Engine: 4.0L
Pulled the pump today and found the hose was loose inside the tank. Maybe that would explain the 15psi? Hard to build pressure when the fuel never leaves the tank HaHa!
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02-07-2019, 02:18 PM
#8
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Year: 1989
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It's the rubber hose coming off the pump. I could actually spin the hose clamp around easily by hand.
My guess is somehow... some way... the hose clamp loosened itself. Does this sound logical? I mean... it has been thirty years.
My guess is somehow... some way... the hose clamp loosened itself. Does this sound logical? I mean... it has been thirty years.
02-07-2019, 02:49 PM
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Year: 90,84
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If you could repair the leaking hose and see correct pressure you could sell the old pump on eBay as functioning, waz one thought...
02-08-2019, 09:13 PM
#12
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Ethanol fuels......the government is helping you..........
02-08-2019, 10:45 PM
#13
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Year: 1988
Model: Cherokee
Engine: 4.0
Gates Ethanol fuel hose
Barricade® Fuel Injection Hose
Aproved for use with Gasoline, Ethanol/Gasoline blends (gasohol) such as E10, E15 or E85, Diesel.
https://www.gates.com/us/en/fluid-po...-pkg/p/p100111
Plus look for these clamps
Barricade® Fuel Injection Hose
Aproved for use with Gasoline, Ethanol/Gasoline blends (gasohol) such as E10, E15 or E85, Diesel.
https://www.gates.com/us/en/fluid-po...-pkg/p/p100111
Plus look for these clamps
02-09-2019, 05:05 AM
#14
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Year: 1989
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New pump is putting out proper pressures, so the old pump is going out to pasture. Maybe I'll put 12V on it someday, maybe I won't.
Small fuel leak at the fuel pressure regulator... nothing a new o-ring can't fix... and I'm on my way!
Small fuel leak at the fuel pressure regulator... nothing a new o-ring can't fix... and I'm on my way!
02-09-2019, 06:16 AM
#15
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Gates Ethanol fuel hose
Barricade® Fuel Injection Hose
Aproved for use with Gasoline, Ethanol/Gasoline blends (gasohol) such as E10, E15 or E85, Diesel.
https://www.gates.com/us/en/fluid-po...-pkg/p/p100111
Plus look for these clamps
Barricade® Fuel Injection Hose
Aproved for use with Gasoline, Ethanol/Gasoline blends (gasohol) such as E10, E15 or E85, Diesel.
https://www.gates.com/us/en/fluid-po...-pkg/p/p100111
Plus look for these clamps