Hi guys,

Whenever I go to refill petrol, and I unscrew the fuel cap, there is a TON of vapor/gas that escapes out as I open the thing. I let it out slowly but am amazed at just how much there is. It's a solid 10 seconds of "hissssssssssssssssssssssssssssssssssssssssssssssss sssssssssssssss".

Anyone know what causes this or if its normal? Should I be worried?

As usual, I have never had a car that has ever done this (including rental cars, friends cars, etc...) it's the first time I have ever experienced this

Thanks!

My TL will do this only for a second or so on a hot day....usually when the tank is down to 1/4 or less and I've seen this in other cars as well. Maybe in your case the line that transports the fuel vapours to the charcoal canister in the engine compartment is blocked causing a higher than normal pressure. There is also a purge valve which vents the tank when manifold vacuum is above a certain figure....it may be playing up or the vacuum hose to the valve is split preventing the tank from venting.

On a really hot day with not much petrol in the tank, it can hiss a lot. Try filling up on a cold day, or at night, and do so when there is still a quarter of a tank of juice. As above though, worth checking the vapour catch and purge system.

http://www.aussiemagna.com/forums/showthread.php?t=14530

Its pretty normal on a well made/maintained car, you have no vapour leaks...You dont need to let it out slowly, unless you enjoy it...
I'd be worried if it never made a noise....

You should hear it when I open mine every 6+ weeks........

lol



:ninja:

if you have no hiss noise it may indicate a pressure loss somewhere.

my TJ hissed lots but my tl doesnt Mmmm I had a bad fuel leak had that fixed but still no hiss and uses lots of fuel and get 13.1 on average. Can this be the cap??