I have a 2003 Lancer. Gas takes forever to go down filler neck. Can't put in half a gallon before gas spills out. Takes about 5 minutes for that little bit of gas to go down. I've replaced the purge valve by engine, the charcoal canister and valve next to it. Still can't fill up. I think the plastic piece that acts like a door to the fuel tank won't open. It's at the end of the filler neck but it's fitted inside the tank neck. I'm not sure what it's called or how it works. Does anyone know?