when i take off my gascap it releases alot of pressure?

[ll3lue]

my gascap seems to be holding in alot of pressure..when i take off the cap it goes "whissshhh" lol and its pretty loud an blows out air..what the hell is this? lol the car runs fine...

 

[Jerryl]

Is the vapor canistor working correctly and not leaking pressure in the tank under boost?

 

[ll3lue]

Is the vapor canistor working correctly and not leaking pressure in the tank under boost?

how do i check to make sure its working right?

 

[Jerryl]

Try this link ..... http://www.turbobuick.com/forums/showthread.php?t=133375&highlight=charcoal+canister+solenoid