fuel pump wont kick on?????
#1
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Year: 1998
Model: Cherokee
Engine: 4.0
fuel pump wont kick on?????
1990 jeep cherokee 4.0, a4, 4x4. the jeep ran about 4 months ago, i went to start it and the fuel pump wont kick on. i checked the fuel rail and nothing...
yall have any ideas. is there anything that will just go bad that controls the fuel pump?
yall have any ideas. is there anything that will just go bad that controls the fuel pump?
#2
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Year: 1991
Model: Cherokee
Engine: 4.0
Fuel pump is dead 25%
Key switch is dead 20%
PCM is dead 3?
Relay is dead 1%
Chipmunk ate wires 1%
#3
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Start at the fuel pump with a test light, then move to the fuel pump relay on the right inner fender. I think there is a fuse for it too, but I have not had to trouble shoot the fuel pump yet.
#4
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Year: 96
Model: Cherokee
Engine: 4 liter
Mine did that. Check the Crankshaft Position Sensor about 11 o'clock on the trans bell housing viewed from the front.
If it doesn't work, the pump won't prime. Cheap, easy r and r.
If it doesn't work, the pump won't prime. Cheap, easy r and r.
#5
mine did the same thing after sitting for a while. i hit it with starting fluid and it has started fine every since. not sayin this will help but just puttin it out there. make sure the grounds are good. the fuel pump is grounded to the tank/body. if you dont have a good ground from the battery to the body or the engine to the body. (been there too)
#6
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Year: 1998
Model: Cherokee
Engine: 4.0
battery is good had a charger hooked up to it. wish this was the problem.
good grounds
all wires good
gonna check relay and fuse next.
and pcm bad??? hows this happen and how offten. do they just self destruct or what?
whats the omh's suppose to be on the cps when you check it?
good grounds
all wires good
gonna check relay and fuse next.
and pcm bad??? hows this happen and how offten. do they just self destruct or what?
whats the omh's suppose to be on the cps when you check it?
#7
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Year: 1991
Model: Cherokee
Engine: 4.0
battery is good had a charger hooked up to it. wish this was the problem.
good grounds
all wires good
gonna check relay and fuse next.
and pcm bad??? hows this happen and how offten. do they just self destruct or what?
whats the omh's suppose to be on the cps when you check it?
good grounds
all wires good
gonna check relay and fuse next.
and pcm bad??? hows this happen and how offten. do they just self destruct or what?
whats the omh's suppose to be on the cps when you check it?
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#9
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#10
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Year: 1987
Model: Cherokee
Engine: 4.0
check your spark.
if you have spark, but no fuel, then you could have;
bad relay
bad fuel pump
most likely culprit on a '90 is a bad ballast resistor. it's white, made of ceramic, long with an offset bolt holding it to the inner fender wall. either located toward the drivers side of the air box, or farther back, same side, near the firewall.
make a jumper wire using two male spade connectors. bypass the resistor, and goop up the ends with some dialectirc grease. then tape over the ends, and never look back.
if you have spark, but no fuel, then you could have;
bad relay
bad fuel pump
most likely culprit on a '90 is a bad ballast resistor. it's white, made of ceramic, long with an offset bolt holding it to the inner fender wall. either located toward the drivers side of the air box, or farther back, same side, near the firewall.
make a jumper wire using two male spade connectors. bypass the resistor, and goop up the ends with some dialectirc grease. then tape over the ends, and never look back.
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Year: 1987
Model: Cherokee
Engine: 4.0
take two wires attatched to a 12v battery, climb under the jeep, disconnect the fuel pump, connect negative to black, and positive to the other large wire (green, purple, or orange...can't remember lol). if that makes the pump come on, your issue is elsewhere...try replacing the relays near the battery, then start checking the fusible links with a test light.
#15
Did a new pump make the fix? I'm having nearly an identical problem but after 2 new pumps, and trying to make them run by wiring them direct..still not running.
Going to take the latest new one out and bench test it. Been two months dicking with this problem.....grr...
Going to take the latest new one out and bench test it. Been two months dicking with this problem.....grr...