1966 coupe gas gauge

The gas gauge doesnt work in my '66 mustang coupe. Ran out of gas the other day, that sucks right? RIGHT! Anyway, how do I start to trace the problem? There is a wire in my trunk thats not plugged into anything, just laying there with the end stripped. The guy who had the car before me really screwed the wiring on it. Just wondering where to start looking. Also if the wire in my trunk is for the gas gauge would I be able to tie it into a wire that goes hot with the key on and my gauge work fine?

Hey there. I had a problem on my '66 similar to yours. There should be a wire in the trunk that exits through the floor near the passenger compartment side of the gas tank, if i remember correctly, to the fuel sender. Otherwise the problem is most likely your fuel sending unit. It is that 2-3 inch diameter circular plug that your fuel line comes out of. It is supposed to have a wire that runs to it which goes on that little peg(the wire should have some kind of black protective wrap around it like the tail light wiring). To remove this unit you simply twist it about a quarter turn and pull it out. This unit has the fuel float assembly on it (which is probably some metal alloy of some kind with some holes in it by now, so it sinks instead of floating or may simply be stuck, thus giving you your inaccurate fuel level). When replacing make sure you get the rubber seal properly seated/centered between the sender and the gas tank. Hope this helps! and Good Luck!

The gauge stays pegged on empty. You would think if its a flaot problem then it would move around some, going over bumps, around sharp turns, ect.

That is what mine did when I bought mine. It was pretty much rusted in place... from the gas eating on it over the years. It might be the guage itself. I would try the fuel sender first though.

Don't forget to drain the fuel Tank! If your tank has a drain it would be on the passenger side at the front of the tank. You can get a replacment Fuel Sender unit from http://www.johnsmustang.com in Houston.