Possible bad fuel pump?
#1
Possible bad fuel pump?
Sometimes my jeep will start and run for a while and other times it's will shut right off after it starts. Also sometimes happens when I'm driving and it will start chugging but I will just rev it up and it will be fine? Is it the fuel pump or something else?
#5
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Year: 1989
Model: Cherokee
Engine: 4.0l 6 cylinder
Originally Posted by askingxforxit
IAC could be the cause...
#7
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Year: 1989
Model: Cherokee
Engine: 4.0l 6 cylinder
Originally Posted by 96manual2door
It will let you rev it sometimes but other times that will also kill it...
But I'm not there diagnosing it
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#10
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Doesn't a 96 still have a fuel pump ballast resistor mounted on the driver's side fender well? If the connectors are loose on a ballast resistor or it's going bad, the symptoms will mimmick a failing fuel pump.
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Year: 1996
Model: Cherokee
Engine: 4.0 HO Straight Six
Originally Posted by cruiser54
Doesn't a 96 still have a fuel pump ballast resistor mounted on the driver's side fender well? If the connectors are loose on a ballast resistor or it's going bad, the symptoms will mimmick a failing fuel pump.
#12
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Supplies 12V to pump on starting and then reduces the voltage on Run to keep the fuel pump quiet.
My wife complained that at times her 88 was acting like it die before the fuel pump failed. Me doing what I do, RCBRC, I checked each of the 2 connectors at teh ballast resistor and found they weren't grasping the tabs tightly. Fixed them up and no more problems.
#13
I cleaned the iac that didn't change anything. I also took a fuel line off and put it in a bucket turned it on and it would give gas for a couple secs but should it keep running or is it supposed to shut off like that?
#14
Originally Posted by cruiser54
Renix does for sure. Located on the driver's side inner fendeer near the air cleaner box.
Supplies 12V to pump on starting and then reduces the voltage on Run to keep the fuel pump quiet.
My wife complained that at times her 88 was acting like it die before the fuel pump failed. Me doing what I do, RCBRC, I checked each of the 2 connectors at teh ballast resistor and found they weren't grasping the tabs tightly. Fixed them up and no more problems.
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Year: 1999
Model: Cherokee
Engine: 4.0
1. No ballast resistor on a 96. 93 was the last year.
2. The ONLY way to test fuel delivery is with a gauge. NO shortcuts. Many parts stores will rent you this tool inexpensively. For a 96, you should have 49 psi, plus or minus 5 psi.
3. Be darn sure all tuneup hardware is fresh. Champion copper plugs gapped to .035, new high quality plug wires, cap and rotor. The importance of good tuneup hardware cannot be overstated.
4. If the above all checks out, it is possible that you are on the front end of a crankshaft position sensor problem.
2. The ONLY way to test fuel delivery is with a gauge. NO shortcuts. Many parts stores will rent you this tool inexpensively. For a 96, you should have 49 psi, plus or minus 5 psi.
3. Be darn sure all tuneup hardware is fresh. Champion copper plugs gapped to .035, new high quality plug wires, cap and rotor. The importance of good tuneup hardware cannot be overstated.
4. If the above all checks out, it is possible that you are on the front end of a crankshaft position sensor problem.
Last edited by tjwalker; 04-06-2012 at 05:28 PM.