gas tank pressure

[XJ6GUY]

hi all,

whenever i remove my gas cap it lets out a lot of pressurized air.is this normal? or do i have some type of filter blockage?if so,wheres the filter i need to check?........thanks


tom

 

[JonM]

Alot of pressure is not normal...a little is. You may have blockage in the line running from the cannister at the front of the car to the back...remove both ends and see if you can blow air through it. You will need a compressor. You could also have a bad cap.

 

[John Robinson]

Fuel tank preassure

On page 244 of my owners manual it has a caution about fueling the Corvette

If you get gasoline on you and then something ignites it you could be badly burned. Gasoline can spray out on you if you open the fuel filler cap too quickly. This spray can happen if your tank is nearly full, and is more likely in hot weather. Open the fuel filler cap slowly and wait for any "hiss" noise to stop. Then unscrew the cap all the way.

It sounds like they are saying we will have preassure when we remove filler cap from the expansion of the fuel when it comes from the cool ground to the heat of summer:confused

 

[Ken]

Vapor pressure increases with temperature. The fuel system on a Corvette (or any late model vehicle) is sealed until it's purged.

 

[tigmaned]

i noticed putting gas in today when i took the gas cap off the pressure made the little metal unleaded door fluter up and down? its not a hot day, about 50 i think. i have a new cannister, and changed out the lower lines coming out of the cannister since the old one had stuff almost blocking them? i guess i can try running compressed air threw that side to the cannister fromt the fuel tank?

 

[Rogier]

You can buy a filler cap with pressure valve inside everywhere. This should also be mounted on you corvette within the fillercap or somewhere else on the tank. If you have pressure this is blocked. That fuel build up pressure in a closed tank is normal that's why they designed these overflow gadgets for gastanks. Either way it's easy to solve with a good fillercap.

Best regards,

 

[tigmaned]

well i tried some thing with my return line last night. i have been told before to chck for a blockage, so last night i did some tihng aobut it. i discontected the return line at the cannister and fuel sending unit and blew it out with compress air. well it seems to be running smoother, idles down better too. i alway thought my throttle body was sticking, i would come to a stop light let off the gas and she still idled kind of high for a while, well no more!! funny how some thing so little did it!!