toravir

Whenever i open the gas cap, i hear either pressure releasing into the gas tank or from the gas tank.. i guess the venting / evap is broken. I read about not doing the over-filling could cause this just now and i am guilty of overfilling.. Now how do i go about checking if it is a totally blown charcoal canister or just some clogged up connecting tube.. i have the Haynes Repair manual but it says very little about which hoses goes where etc.. can some one give me some tips ?

Also this is a really old car - i am hoping to keep it usable for another year tops. Or can i just periodically keep opening and closing the gas cap to work around this problem.

thanks!

Child_uv_KoRn

iTrader: (7)

vent valve must be stuck closed

DennisMik

iTrader: (2)

Pollution laws require that gasoline fumes not be released into the air, so when the engine is running, vacuum is applied to the gas tank and the fumes are sucked into the engine and burned up. When you turn off the engine, the vacuum is slowly released. Sometimes people will hear a wheezing sound while this is happening. But if you remove the gas cap before the vacuum is removed, you will get the pressure sound you are referring to.

TallTom

If the car drives fine and isn't throwing a code, I would just leave it alone.

Prophecy99

iTrader: (1)

yea, i hear the tank relieve pressure all the time when i take the cap off ..... if youy have no codes, then no issues...

toravir

Thanks for your replies!! I am going to leave it alone.

Roymg

For my 2003 Max I recently got a recall from Nissan for the evap system. If having problems filling with gas they say there may be a blocked tubing that needs to be cleared. Any thing else found wrong with the evap would be extra. The car has 147,000 miles. So far, I can still fill up. U can try to add gas with the engine running but is not advisable.