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1998 dodge ram 1500 fuel pump not working

Old Jul 28, 2025 | 01:58 PM
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Can confirm i did this with no change. Trying to verify the circuit and see if there is a ground issue
 
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Old Jul 28, 2025 | 01:59 PM
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Jump the fuel pump relay. Pin 30, to pin 87. The pump should run, if the pump is good, and the wiring is intact.
 
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Old Jul 28, 2025 | 02:09 PM
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Just because a ground allows you to test doesn't mean it can carry a lot of current. I think what you are seeing at the connector when it is plugged in is ghost voltage. Have someone cycle the key on and test again.
 
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Old Jul 28, 2025 | 02:14 PM
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I will test voltage at connector when connected to pump when I jump the relay when I get home. I checked the voltage multiple times when I turn key on with the tester connected to the connector while plugged in. Got the same reading of .76 volts.
 
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Old Jul 28, 2025 | 02:27 PM
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Originally Posted by Straley91
I will test voltage at connector when connected to pump when I jump the relay when I get home. I checked the voltage multiple times when I turn key on with the tester connected to the connector while plugged in. Got the same reading of .76 volts.
If that is the true reading I would back trace the wire. I bet it's broken somewhere.
 
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Old Jul 28, 2025 | 02:32 PM
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Trying to trace the circuit and it appears to run along the frame to another connector behind the driver side tire, which then runs to the tipm. Everything appears to be in working condition. Is the circuit grounded through the pcm?
 
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Old Jul 28, 2025 | 02:52 PM
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I think the ground is up front, below the batter, on the fender well, or some such. On my 98, there are a HOST of wires that ground there, and most of them were rusted and broke......
 
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Old Jul 28, 2025 | 03:02 PM
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Roger..I will check in that area and assure all the grounds are good. I'm sure it's something simple and I'm just missing it.
 
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Old Jul 28, 2025 | 03:07 PM
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Originally Posted by Straley91
Roger..I will check in that area and assure all the grounds are good. I'm sure it's something simple and I'm just missing it.
Don't feel like the lone ranger. It took three fuel pumps for me to find a bad ground...... The shop I took it to just weren't that great..... To the point that they existed from just over a year, and then they were bought out, and everyone replaced.
 
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Old Jul 28, 2025 | 03:11 PM
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Fuel pump wasn't my first suspect, when I checked it originally I didn't hear it kick on with key on position, and since the truck wasn't starting and everything else tested good i did the replacement, which was fun with the heat wave going on here and doing it on the street. Once I got it installed and realized it might not be the fuel pump, i tested the old one with a 12v battery and it worked as it should. Awesome.
 
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