fuel problems! gas tank pressure

[xj_punk]

So my 93 xj 4.0 decided that building up pressure in the gas tank and a screaming fuel pump is cool. It will seriously hiss for ten minutes when I crack the gas cap to fill it up and if I take the cap all the way off the fuel will shoot out several feet... Yeah it's awesome. Anyone have an idea?

I dented the tank pretty bad but that was several months ago and it just started doing it. Also I replaced the pump, strainer and filter just over a year ago.

 

[orange]

Clogged, plugged, broken vent system.
(lines mashed? charcoal canister?)

Good Luck,
Orange