Usually old wiring will cause this due to the many poor connections that have built up corrosion over time. I'd suggest running a new accessory power line to the fuel gauge right from the keyswitch... assuming the keyswitch itself hasn't built up high resistance.


1960 GMC Panel w/ 305 V6, 4 Speed TV Repair Van "The Monitor Lizard"
1961 Chevy Apache 20 283, 4 Speed, Hydrovac
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