gas tank

cannot put gas into tank please advise, also my gas guage registers full and is broken 1994 grand marquis

cannot put gas into tank please advise, also my gas guage registers full and is broken what causes back up

Vent is plugged somewhere. Year would help a lot.

Thasnks for the PM. Unplug the wiring from the fuel pump and see if the gauge moves. It should drop to empty. If it does the sending unit is at fault. If it does not move, check wiring or gauge. If it moves and you need to replace the sending unit you need to lower the tank anyway, check all hoses and connections to be sure there is no restrictions in the vent areas.