Fuel pump out again. I'm losing it.
07-02-2016, 08:18 PM
#62
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07-02-2016, 08:33 PM
#63
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When checking the relay for continuity should I see close to zero or infinite? I did some research and it was talking about if it was normal closed or normal open that one is one way and one is the other. I don't know which the cherokee is so I may have tested it wrong months ago.
07-02-2016, 08:48 PM
#64
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If the relay were an issue the voltage wouldn't be right. You can swap the second, (fuel pump), with the fourth AC, if you like.
Maybe clean out the tank, stick another pump in there, and stop running it near empty and see how it goes. Idk, but it might be possable you cooked the first few by running on empty too much. That's what they say anyway. Actually anytime you are running fuel is going through the pump...but "they" say having it in the fuel cools it.
Cruiser did find a bad wire once, in the tank between the pump and the deal. Something to check when you have it out.
Maybe clean out the tank, stick another pump in there, and stop running it near empty and see how it goes. Idk, but it might be possable you cooked the first few by running on empty too much. That's what they say anyway. Actually anytime you are running fuel is going through the pump...but "they" say having it in the fuel cools it.
Cruiser did find a bad wire once, in the tank between the pump and the deal. Something to check when you have it out.
07-02-2016, 08:51 PM
#65
When checking the relay for continuity should I see close to zero or infinite? I did some research and it was talking about if it was normal closed or normal open that one is one way and one is the other. I don't know which the cherokee is so I may have tested it wrong months ago.
07-02-2016, 10:16 PM
#66
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Thread Starter
If the relay were an issue the voltage wouldn't be right. You can swap the second, (fuel pump), with the fourth AC, if you like.
Maybe clean out the tank, stick another pump in there, and stop running it near empty and see how it goes. Idk, but it might be possable you cooked the first few by running on empty too much. That's what they say anyway. Actually anytime you are running fuel is going through the pump...but "they" say having it in the fuel cools it.
Cruiser did find a bad wire once, in the tank between the pump and the deal. Something to check when you have it out.
Maybe clean out the tank, stick another pump in there, and stop running it near empty and see how it goes. Idk, but it might be possable you cooked the first few by running on empty too much. That's what they say anyway. Actually anytime you are running fuel is going through the pump...but "they" say having it in the fuel cools it.
Cruiser did find a bad wire once, in the tank between the pump and the deal. Something to check when you have it out.
1. Drop the tank and clean it as good as possible.
2. Go ahead and replace relay
3. Keep the resistor bypassed
4. Make ground extra shiny, even though it tested good.
5. Put a new pump in and try to keep as much gas as possible although, sometimes it's tough when money is tight, but I'll try.
6. Hope for the best since, with y'all's help, done all I can do and checked and double checked everything.
I want to thank everyone for sticking with me and trying. I know it's only so much y'all can do and then it comes to a point where it's just a puzzle as to why it's doing what it's doing. If y'all think of any more wires, grounds, or anything to check just let me know.
07-02-2016, 10:50 PM
#67
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I also meant to say I'm going to pour a bottle of Lucas cleaner in the tank when I put new one and change fuel filter
But I came back to say that I am constantly reading the past two days and I'm going crazy but I may have just stumbled upon something.
I was reading about a guy who drove a 90's blazer and his was doing the same thing. Humming and stalling.
He changed the fuel filter and it stopped humming and ran fine for a day then started back. So he had a clogged fuel filter due to trash in the tank causing his problem so hopefully that is my problem since all voltage and continuity was correct. Tomorrow afternoon I am going to take old filter off and brake it open and see what I see. Then proceed to cleaning the tank Monday.
But I came back to say that I am constantly reading the past two days and I'm going crazy but I may have just stumbled upon something.
I was reading about a guy who drove a 90's blazer and his was doing the same thing. Humming and stalling.
He changed the fuel filter and it stopped humming and ran fine for a day then started back. So he had a clogged fuel filter due to trash in the tank causing his problem so hopefully that is my problem since all voltage and continuity was correct. Tomorrow afternoon I am going to take old filter off and brake it open and see what I see. Then proceed to cleaning the tank Monday.
07-03-2016, 12:25 AM
#68
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Yes. They are good and tight and have no corrosion that I can see.
I will be checking in the tank for trash tomorrow when I get the back a little higher. After that I will have done everything that has been suggested.
Also I thought about what the previous owner told it did to him. He said he drove it and it started going out then he took it home.
He would crank it up and move around his drive way and it would die. He'd park back in shed. Then it got to the point it wouldn't start at all.
This is what it's basically doing to me except I never make it to the point that it won't start because I keep changing the pump. But it's definitely cutting off on me in on the roas after it starts humming and going out. Almost got me killed in early June.
I said all that to say that whatever is burning up the airtex pumps is the same thing that burned up the stock pump. So it's probably not going to do me any good to burn up a Bosch.
It has to be something simple because the jeep runs too good for 2-4 weeks. Then it hums for a week. Then it hums and starts cutting off.
I will be checking in the tank for trash tomorrow when I get the back a little higher. After that I will have done everything that has been suggested.
Also I thought about what the previous owner told it did to him. He said he drove it and it started going out then he took it home.
He would crank it up and move around his drive way and it would die. He'd park back in shed. Then it got to the point it wouldn't start at all.
This is what it's basically doing to me except I never make it to the point that it won't start because I keep changing the pump. But it's definitely cutting off on me in on the roas after it starts humming and going out. Almost got me killed in early June.
I said all that to say that whatever is burning up the airtex pumps is the same thing that burned up the stock pump. So it's probably not going to do me any good to burn up a Bosch.
It has to be something simple because the jeep runs too good for 2-4 weeks. Then it hums for a week. Then it hums and starts cutting off.
07-03-2016, 06:50 AM
#69
You are near Charlotte, the XJ capital of the US............dimes per dozens.........
I guarantee you that I could have found a complete tank with pump and assembly for $30 in your area.
Clean and swap.
As for a relay going bad- like any other electrical device/switch, they can work today and not tomorrow. Heat up and melt down, which is exactly what happened to me, first failure of my MJ after I got it.
I guarantee you that I could have found a complete tank with pump and assembly for $30 in your area.
Clean and swap.
As for a relay going bad- like any other electrical device/switch, they can work today and not tomorrow. Heat up and melt down, which is exactly what happened to me, first failure of my MJ after I got it.
07-03-2016, 07:13 AM
#70
Let me also add this-
Whenever I have a problem such as yours, I start from scratch.
If I believed that I had a wiring/ground problem, such as you may have-
I would buy a 25' extension cord, preferably black, 14g would be large enough for this application.
That gives you three wires. Cut the ends off, cut to length, zip-tie to the fuel line/brake line.
Trace the wire from the resistor back to the relay, cut, attach black wire.
Run white wire to to the neg post of the battery.
Run green wire to the neg post of the battery.
OReillys sells nice two prong pigtails for $6, at the pump end of the cord attach one side of the pigtail, to the pump wire harness out of the tank, attach the other end of the pigtail.
Black to pos and white to neg.
Drill a hole near the tank on the frame where you can insert a 1/4" bolt (bolt becomes a new neg battery post at the rear of the XJ), bolt it to the frame, attach green wire. Now you have a KNOWN ground directly from the battery to the rear of the XJ, now you can attach a KNOWN ground to your tail lights or other in the future.....trailer lights....etc.......
Now, you know for a fact that you have no wiring problems from the battery/relay back to the pump.
It can be done to look professional if you take your time.......this is not a hack fix.
Whenever I have a problem such as yours, I start from scratch.
If I believed that I had a wiring/ground problem, such as you may have-
I would buy a 25' extension cord, preferably black, 14g would be large enough for this application.
That gives you three wires. Cut the ends off, cut to length, zip-tie to the fuel line/brake line.
Trace the wire from the resistor back to the relay, cut, attach black wire.
Run white wire to to the neg post of the battery.
Run green wire to the neg post of the battery.
OReillys sells nice two prong pigtails for $6, at the pump end of the cord attach one side of the pigtail, to the pump wire harness out of the tank, attach the other end of the pigtail.
Black to pos and white to neg.
Drill a hole near the tank on the frame where you can insert a 1/4" bolt (bolt becomes a new neg battery post at the rear of the XJ), bolt it to the frame, attach green wire. Now you have a KNOWN ground directly from the battery to the rear of the XJ, now you can attach a KNOWN ground to your tail lights or other in the future.....trailer lights....etc.......
Now, you know for a fact that you have no wiring problems from the battery/relay back to the pump.
It can be done to look professional if you take your time.......this is not a hack fix.
Last edited by Jeep Driver; 07-03-2016 at 07:19 AM.
07-03-2016, 11:45 AM
#71
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Year: 1990
Model: Cherokee (XJ)
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You are near Charlotte, the XJ capital of the US............dimes per dozens.........
I guarantee you that I could have found a complete tank with pump and assembly for $30 in your area.
Clean and swap.
As for a relay going bad- like any other electrical device/switch, they can work today and not tomorrow. Heat up and melt down, which is exactly what happened to me, first failure of my MJ after I got it.
I guarantee you that I could have found a complete tank with pump and assembly for $30 in your area.
Clean and swap.
As for a relay going bad- like any other electrical device/switch, they can work today and not tomorrow. Heat up and melt down, which is exactly what happened to me, first failure of my MJ after I got it.
07-03-2016, 12:13 PM
#72
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07-03-2016, 01:02 PM
#75
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Year: 1998
Model: Cherokee
Engine: 4.0L
This whole thread has been an entertaining read. I'm waiting for the actual solution to this fuel pump problem but then I stumble upon this beautiful response. Thank you for that laugh Flintstone 
I really wish I could contribute to some diag but this is crazy. Does your XJ have a metal or plastic tank? I can see debris clogging the strainer on the pump but to burn up a pump at the same time multiple times is highly unlikely. I'd be leaning towards it being electrical related. Constant high amperage would more likely cause multiple pumps to fail around the same time. I'm just speculating at the moment though.
And I'll also add that airtex is garbage.
I really wish I could contribute to some diag but this is crazy. Does your XJ have a metal or plastic tank? I can see debris clogging the strainer on the pump but to burn up a pump at the same time multiple times is highly unlikely. I'd be leaning towards it being electrical related. Constant high amperage would more likely cause multiple pumps to fail around the same time. I'm just speculating at the moment though.
And I'll also add that airtex is garbage.