Your wire may be either corroded which will cause high resistance or the gas gauge is bad. If you have a multimeter/ohmmeter check the brown wire for continuity from the gauge to sending unit connection. It should be 0 ohms, anything more and the gauge will read higher than the actual fuel in the tank. The sending unit wire runs under the drivers door sill plate and weather strip, just in case you have to repair or replace it. 
__________________
'72 GMC SWB C1500 Custom, frame-off in progress. 383 SBC, 9:1CR, Comp Cams XE262H, Scat internal balanced crank, Eagle SIR 6" rods, Keith Black dish pistons, Dart Iron Eagle 72/180 heads, Weiand Stealth intake, Stewart stage I water pump, Holley 4bbl vac sec, TH350 with B&M Shift Improver Kit. 12 bolt positraction.   
|