Fuel Guage 1990 cherokee
#16
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Year: 1988
Model: Cherokee (XJ)
Engine: 4.0L
I've made a jumper out of a single U bent wire (installed in place of the fuel pump relay) to run the pump, so yes, you will see indication of 12v power with a tester.
#17
Member
It may be the ballast resistor on the drivers side fender in front of the EGR solenoid, it is for the fuel pump. You can just put a jumper wire between the 2 spade wire connectors to check.
#18
When I rebuilt everything (except the engine, I replaced the resistor and when this happened where the fuel pump quit, I replaced it again with one from ??? Quadtrec is the name. Anyway the first was from Amazon, the second was from a Jeep place. I installed but no avail. New battery, new leads to positive and new ground. Went in the back, pulled spare and cleaned and replaced the connectors for better ground. As stated earlier, I went under and added a ground from the bolt where the bumpstop is at (cleaned and brushed) and added a three way splice to fortify the ground at the connector to the pump. Pump side, not jeep side. So it appears it is the pump or lack of power. I want to test the power. I have not played with checking things since I have never had electrical issues before. I tend to replace. So I will check the relay but I will have to find that information to which holes to plug into. Then I will check the connector going to the pump. I appreciate the advice.
#19
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Year: 1988
Model: Cherokee (XJ)
Engine: 4.0L
The prime is 12v directly through the relay, then kicks down to 9v through the ballast resistor. Have you verified with a fuel pressure gage that you have no fuel pressure in the rail?
#20
I don't have a pressure gauge, but bleeding the fuel rail, it will not spurt anything. Under pressure it will push fuel. I have no pump whine, so it is not going on and when I check the rail, there is no flow. I have not tried pulling the inline to the rail which will dump fuel everywhere, but I can, but I think the outcome will be the same.
#21
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Year: 1988
Model: Cherokee (XJ)
Engine: 4.0L
I think "eye balling" 0 pressure is fairly reliable by pushing the schrader valve. The pressure gage could come in handy later if you are still having issues and have actual pressure that needs to be measured.
#22
I will be checking the relay and plug today. No lift, so going down is hard on a middle age farmer with RA. But has to be done. I will update you on my findings tonight. Thanks again.
#23
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Year: 1988
Model: Cherokee (XJ)
Engine: 4.0L
I just was reading your earlier posts. You say you replaced the positive battery cable. That cable connects to the positive post of the starter relay. There are also 4 fusible links on that same post of the starter relay. One of those fusible links is the power to the fuel pump relay.
#24
I replaced the cables early this summer and have had the vehicle running since, last fall. the fuel pump issue is only a week old. Are those fuse lines coming out of the starter solenoid, Where that spider web of wires are coming out that are bolted in? I have not researched this. So I have no clue where to start. I never took any of that apart. Except for the outside cable which was the opposite of end. and everything was working fine up until I had the power on for a long period s of time when I was working on the doors putting in new scrapers and seals and channels and running the motor up-and-down making sure everything was working properly. Someone told me that I most likely burned up the pump. My fuel pump does not come until Monday. So I would like to check that starter fuse area. But I don't know where to start.
#26
I just was reading your earlier posts. You say you replaced the positive battery cable. That cable connects to the positive post of the starter relay. There are also 4 fusible links on that same post of the starter relay. One of those fusible links is the power to the fuel pump relay.
#27
So I am going to attempt to splice a longer piece. Those connectors are hard to find (they are out there) so I am going to use a spade type and found some insulation boots to put over. That is the plane
When this is done I believe I will be back to figuring out the fuel gauge. Since I have a pump coming, should I replace? I am thinking not or not right away. I plan to pull the cluster and see if the connections are good. After that I guess it would have to be the pump and most likely the float or a ground issue I can not find.
When this is done I believe I will be back to figuring out the fuel gauge. Since I have a pump coming, should I replace? I am thinking not or not right away. I plan to pull the cluster and see if the connections are good. After that I guess it would have to be the pump and most likely the float or a ground issue I can not find.
#28
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Year: 1988
Model: Cherokee (XJ)
Engine: 4.0L
I think you are describing the orange wire with black tracer. That is the power wire that goes to the fuel pump ballast resistor. It is unusual that it would burn through. Good plan to slice and repair it, but I would suggest you do a continuity check on that to ground before the battery is reconnected.
Last edited by dmoe69; 12-11-2023 at 11:06 AM.
#30
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Year: 1988
Model: Cherokee (XJ)
Engine: 4.0L
You misunderstand. Finding a path to ground would be a bad thing, the kind of bad thing that would burn a wire in half. My suggestion that you perform a continuity check is to verify there isn't one. Do you have a multimeter?