Gas smell pressure in tank (1 Viewer)

[kerrye]

Filled the tank up this morning and drove from Denver to Pawnee Grasslands. 80 miles? Hiked for a few hours and drove home. Got out of the truck and noticed a gas smell. Unscrewed the cap and lots of pressure came out. Pushed down on the flapper to get all the pressure out and started putting the cap back on. Heard more pressure releasing. Maybe it's coming from the two holes on either side of the fill tube? Waited about 10 minutes, still getting pressure releasing. Let it sit for 15 minutes went back to it. Smelled gas around it. Loosened fill cap. Can hear pressure releasing if I unscrew about one turn. Can't hear anything with the cap removed. Anyone have any idea what's going on? I did noticed a gas smell about a month ago after I filled up and was slowing down at a stop light.

 

[inkpot]

Some pressure is normal, but if your smelling gas without opening cap, then I would check vent/filler hoses, also small lines going to vapor can under hood. May need to replace cap if it does not hold pressure.

 

[kerrye]

It had a lot of pressure and cap was holding. I am really puzzled as to why the pressure doesn't all relieve almost immediately after the cap is removed. Where is the continued pressure coming from?

 

[blkprj80]

It was hot today. Still 75 up here in Laffy-et. You probably got some of the winter fuel that is boiling off from the warmth.
Where did you buy your gas? I bought some from Murphy's (cheap) and it smelled like dead animals in my shop and pressurized the tank even when it was cold (shop was warm). I went back to decent (?) gas from shell, and it seems to be better.
I think you're a victim of the oxygenated crap fuel we get here in Denver metro area.

 

[kerrye]

bought it at the shell station on Brighton Blvd. But now that you mention it, the last time it smelled I bought it at the new Shell station on S. Santa Fe. It could be crap fuel.

 

[kerrye]

http://www.theoildrum.com/node/1776

 

[Adam R]

This would happen all the time to us when we lived in Colorado, especially at high elevation. Today's crappy gas begins to boil off the more volatile compounds at some fairly low temps. Combine high fuel temps, with low atmospheric pressure and you get a lot of fuel boiling off. Part of the problem is that fuel is continuously cycled through the engine compartment and it just gets hot and stays hot. We've had some real "gusher" experiences with massive venting at 13,000 feet once I pulled the gas cap. I finally said enough and now have a diesel under the hood. Really didn't like the idea of my kids sitting on top of fuel/vapor bomb.

Adam

 

[scottryana]

Yep I pulled my gas cap lid on the top of Imogene and it spewed for a good 3-4 min, I ended up putting the cap on before it stopped.

The crux of the problem might be bad gas but if the charcoal canister wasn't clogged it wouldn't be an issue. So change your charcoal canister.

 

[kerrye]

Thanks. I was wondering about the charcoal canister. After seeing the OE price, I ordered the Pontiac alternative from RockAuto for $52.