'91_stangman_707

Okay so. My '91 mustang gt is blowing gas out of an over flow line that exits my body kit on the passenger side all the way in the back corner! What i need to know is what could make it do this? But this only happens when its a really hot day. And if i stop every five minutes and loosen the gas cap to let the pressure out of the tank it doesnt do it as bad! Someone please help me!

LOWCOP

the line is the overflow/overfill. sounds like your cap is not venting correctly