Fuel pump out again. I'm losing it.
07-01-2016, 06:23 PM
#16
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
It means keep the resistor bypassed. and quit buying any other pumps than Bosch.
07-01-2016, 06:29 PM
#17
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The only reason I didn't get Bosch in the first place is they don't make a Bosch assembly for the year 89 anymore and I really couldn't afford the dealership one. I was in a corner cruiser.
07-01-2016, 06:36 PM
#18
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Year: 1990
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Ok. So it was the ballast resistor just as the other guy mentioned (can't remember username) the whole time.
The only reason I didn't get Bosch in the first place is they don't make a Bosch assembly for the year 89 anymore and I really couldn't afford the dealership one. I was in a corner cruiser.
The only reason I didn't get Bosch in the first place is they don't make a Bosch assembly for the year 89 anymore and I really couldn't afford the dealership one. I was in a corner cruiser.
What's wrong with replacing just the pump?
07-01-2016, 08:13 PM
#19
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Year: 90,84
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My meter is here in the desk and my Jeep three steps out the door, so I checked mine. Draws 2-1/2 Amps. The cheap Harbor Freight ($5), meter can measure amps up to 10 Btw.
07-01-2016, 08:46 PM
#20
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My mind tells me that since the ballast resistor was screwing with voltage so bad, that is what is wrong but my gut says nope, too good to be true.
07-01-2016, 08:49 PM
#21
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Ok it will most likely be Monday before I get to exchange it so that leaves a couple days to tinker. I will check the amps since it appears to be easy.
My mind tells me that since the ballast resistor was screwing with voltage so bad, that is what is wrong but my gut says nope, too good to be true.
My mind tells me that since the ballast resistor was screwing with voltage so bad, that is what is wrong but my gut says nope, too good to be true.
Keep in mind you're checking for DC volts, not amps.
07-01-2016, 09:05 PM
#22
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PS I do search all these things and try to understand them. Sometimes I learn a lot. sometimes I have to ask for a spell out. Sorry.
07-01-2016, 09:20 PM
#23
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No need to apologize. None of us were born knowing this crap!! LOL.
Set you meter to the lowest DC Volts scale. Use the red lead to probe for power while making sure the black is on a good ground.
Wanna see a tutorial?
Set you meter to the lowest DC Volts scale. Use the red lead to probe for power while making sure the black is on a good ground.
Wanna see a tutorial?
Last edited by cruiser54; 07-01-2016 at 09:23 PM.
07-01-2016, 09:35 PM
#24
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Use Ammeter, Operate Ammeter, Measure Amperage, Measure Amps
To test amp draw I unplugged the rear wire off the resistor. Then on most meters you need to move one of the leads, (the red), to the socket that says "10 amps" or something like that. Set the selector on amps. The other stays on "com". Now you run power through the meter from the wire to the blade on the resistor. Start the Jeep. If there is a negative sign that's OK, you just have it reversed, no mater.
Now don't forget to put that wire back! If you go to check volts with it plugged in the amp socket it will be a direct short and fry something. (or blow the fuse in the meter)
To test amp draw I unplugged the rear wire off the resistor. Then on most meters you need to move one of the leads, (the red), to the socket that says "10 amps" or something like that. Set the selector on amps. The other stays on "com". Now you run power through the meter from the wire to the blade on the resistor. Start the Jeep. If there is a negative sign that's OK, you just have it reversed, no mater.
Now don't forget to put that wire back! If you go to check volts with it plugged in the amp socket it will be a direct short and fry something. (or blow the fuse in the meter)
Last edited by DFlintstone; 07-02-2016 at 11:27 AM.
07-01-2016, 09:38 PM
#25
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To test amp draw I unplugged the rear wire off the resistor. Then on most meters you need to move one of the leads, (the red), to the socket that says "10 amps" or something like that. Set the selector on amps. The other stays on "com". Now you run power through the meter from the wire to the blade on the resistor. Start the Jeep. If there is a negative sign that's OK, you just have it reversed, no mater.
Now don't forget to put that wire back! If you go to check volts with it plugged in the amp socket it will be a direct short and fry something. (or blow the fuse in the meter)
Now don't forget to put that wire back! If you go to check volts with it plugged in the amp socket it will be a direct short and fry something. (or blow the fuse in the meter)
07-01-2016, 11:48 PM
#26
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No need to apologize. None of us were born knowing this crap!! LOL.
Set you meter to the lowest DC Volts scale. Use the red lead to probe for power while making sure the black is on a good ground.
Wanna see a tutorial?
How To Use A Multimeter - YouTube
Set you meter to the lowest DC Volts scale. Use the red lead to probe for power while making sure the black is on a good ground.
Wanna see a tutorial?
How To Use A Multimeter - YouTube
However I do a lot of sitting and thinking. If the resistor didn't have voltage going through it. How would the jeep start and even run. Or could it just be an old worn resistor and not functioning properly thus not allowing enough voltage, prematurely burning up the pump? Hope that makes sense as I am getting a bit confused on what I'm supposed to be checking. I believe I need to check the voltage at the ballast resistor, correct?
You and Dfflinstone are really a great help. Everybody else too, hopefully others will learn off this thread.
07-02-2016, 12:13 AM
#27
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You can check it at the resistor just for fun. Both sides wiith it running. What do you see? It ain't your problem I bet.
Flintstone threw a curve ball about amps. Ignore that for now.
Flintstone threw a curve ball about amps. Ignore that for now.
07-02-2016, 09:58 AM
#28
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I just checked the ballast resistor voltage. On the side closest to steering wheel it was 9.4 and on the side closest to head light it was 14.1
07-02-2016, 10:03 AM
#29
07-02-2016, 10:18 AM
#30
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What if it then burned it out quickly. I'd be in a worse situation. I think I should try to find out what's burning up the NAPA firsr. I know they are not good but they shouldn't burn up at exactly the same mileage. I hate it but I have a problem.