I had a TSB on a vehicle for the same thing, There is a valve just like the one at the top of the filler neck down where the filler hose goes into the tank, it's a one way valve and when it malfunctions, fuel only seeps by it, it doesn't open at all..It was fun to replace by the way..lol..Required a tank drop for a $2 part.
20 year old technician in training
95' XE 4X4:
Rear SensaTrac Coil-Overs
Plasma White Headlights w/100+ watts of fogs on brush guard
Alpine monoblock with 2 10'' Alpine Type S in a sealed box