New Tank....

 

Yes, the sender could be why your gauge isn't working, or the gauge it's self could be bad, but i think it's just the sender.

 

I would buy the new tank. I paid about $119 to get the new tank, float, sending unit, etc.

Wasn't that hard to put the new tank in and strangely enough I get better gas mileage since I replaced the tank...LOL!