now the fuel gauge does not work properly?

1997 GMC SIERRA
100,000 MILES • 5.7L • V8 • 4WD • AUTOMATIC
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EMPTYPOCKETS81
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I replaced the fuel tank in my truck listed above k1500 with one from a 98 k1500, the fuel pump & sending units are different, now the fuel gauge doesn’t work properly. The sending unit is not faulty nor the gauge. Is there anything i can do to make the 97 gauge work with the 98 sending unit.
Sep 8, 2024 at 10:03 PM
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STRAILER
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You might be able to add a low resistance resistor (5 ohm) to help adjust the gauge reading. They don't give us exact resistance readings for this so it will be trial and error. It is the dr/blu wire. I noticed there is a fuel pump balance module as well so that might be having an issue. Here are the wiring diagrams so you can see how the system works. Check out the images (below). Please let us know what happens.
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Sep 9, 2024 at 9:03 AM