Jake53,
SoTxBoTi stated it nicely. If you gauge goes from Empty to Full when you turn on the ignition, I would bet the gauge is good.
Here are the tests (for the items in SoTxBoTi's list):
-the tank is full. [you have tested this?]
-the tank is not grounded properly. [run a ground wire from the metal fuel tube (clean the metal) that comes out the tank to a good ground - right to the negative lead on the battery]
-there is a bad connection/open circuit in the wiring going to the sender unit. [run a wire from the sender pole on the fuel gauge to the post on the sender unit in the fuel tank]
-the "secondary coil is open. [take the sender unit out of the fuel tank and bench test it]
I hope someone corrects me, if I am wrong. I have done these tests successfully many time but seem to have a hard time describing them correctly.
Good luck,
Tim
