Author Topic: Fuel Gauge Won't read above 3/8th of a tank  (Read 2632 times)

Offline Hutch998

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Fuel Gauge Won't read above 3/8th of a tank
« on: July 20, 2016, 03:55:01 pm »
I'm having a hard time figuring out why my gauge does this. I put enough gas in to where it spills out of the fill tube, yet it won't read even to half. I have dual tanks, I'm unsure of the condition of the right tank. I'm only using the left (driverside) tank. They look to be the same size, so why wouldn't it read to at least half? I'm mildly clueless when it comes to wiring, so hopefully one of you experienced guys could help me. Thanks ahead of time.
78' K10
86' K20
94' K2500

Offline hatzie

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Re: Fuel Gauge Won't read above 3/8th of a tank
« Reply #1 on: July 20, 2016, 04:35:31 pm »
Usually this is the calibration resistor on the gauge. 
You can pull the gauge out of the cluster bucket and test the Ohmage from the gauge ground terminal to the gauge sender terminal.  Full should = 90ohms.

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Offline VileZambonie

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Re: Fuel Gauge Won't read above 3/8th of a tank
« Reply #2 on: July 20, 2016, 08:36:02 pm »
Pop the sending unit wire off and turn the key on. See if it swings past full
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