How does the fuel gauge work?

[subway]

did the fuel gage work before you pulled the tank? i dont have a wiring diagram but black is usually always the gound and the color is the signal wire. make sure you have continity to ground through the black wire. douse the gage move if you disconnect the harnes from the sending unit?

 

[subway]

o and the part about the short....if the signal wire were cought some where and grounded out in the frame somewhere that would peg the gage.

 

[Squirreltow]

Found the short in the wire. Thanks Jred.
Was just looking for the true reason that the gauge would peg out as I thought it would move to the other extreme.