Gas gushes out of gas cap after a fill-up

[Theodore]

Have had our '90 Wagoneer since August, but between not running right & being in the shop, yesterday was the first time i had to buy gas.

At the pump, when i opened the cap, there was a slight rush of air as pressure/vacuum? released. i filled the tank til it clicked & thought it be a good idea to add fuel injector cleaner.

So we ran down the road a mile or so to the parts store & got some. When i opened the cap this time, about a 1/2 pint of gas shot out under pressure. Have never seen anything like this before.

Is there a trick to open the gas cap to not get wet with gas? Or, can i only run the tank 3/4’s full?

Here's pic of the gas cap we have.

[wiley-moeracing]

your vent hose is blocked/kinked.

[Theodore]

your vent hose is blocked/kinked.

You nailed it. Turns out the evap system is gone, and the 2 lines coming from the gas tank are capped off.

Have seen comments elsewhere on the forum re: either using a vented gas cap, removing the gasket from the non-vented cap, or adding a fuel filter at the end of the line to enable venting without enabling dirt/moisture to enter the system.

I'd prefer not to go the vented cap route, so am thinking about adding an inline fuel filter to the line, until I can do something permanent. Am wondering what other issues will be caused by going this route vs. replacing the evap canister.