Fuel leak, HELP????

[sidewayzsc300]

89 240sx coupe.
Now that the hot days rolled into california i cant fill my car up past 3/4 of tank. If i have more that 3/4 tank of gas, fuel is pushed through the vent line and out my charcoal canister. At first I though i may have overfilled my tank but it even at happens at 3/4. After i get below that its fine, no problems. i have to open gas cap to releive that pressure in the tank and the fuel leak stops. Anyone have any ideas??????

[MaximA32]

Sounds like the something is going on with the pressure not being released properly from the fuel tank. I'm gonna move this over to 240 Tech to see if someone else has a better idea.

[sidewayzsc300]

Anyone? Is there some sort of check valve to stop liquid fuel that far up in the system? Should the gas cap vent at certain pressure for pretection?

[compactfean]

i would check the vent tube all the way from the tank to the charcoal canister for kinks. Most likely you are gonna need a new charcoal canister though.

[sidewayzsc300]

bump..??????

[MaximA32]

Did you not see what compactfean said?

[sidewayzsc300]

no i didnt sorry, i will check it out and update for further help thankx