this morning i noticed fuel dripping slowly from the what i believe is the vapor storage canister its a rectangular looking box where there appears to be a hose to it. I cant tell if it is leaking from that box it appears that nothing else is leaking except for it dripping down the canister. Is this an indication that the canister is bad? and if it is bad would that cause a fuel leak when i take the fuel pressure off it seems to stop
Thanks and I could sure use a quick reply its the family van and i am stuck without it
1992 e150 conversion van 302 v-8
Mike

 

If you are talking about the black canister on the passenger wheel well, yeah, that's the carbon canister. There should be a pair of hoses coming off of it. One of them is a vapor vent from the gas tank, the other goes to the throttle body via the purge valve.

I believe there is a valve or orifice on the vapor line near or on the gas tank that is supposed to prevent liquid gas from making the journey enginewards. Maybe that valve/orifice is the culprit?

Do you have dual gas tanks? The only reason I ask is that there is a known issue with the valve that switches between the tanks. Mine went about 18 months ago. I was driving down the interstate and a horrified motorist pulled alongside me flailing his arms like a madman. One of the tanks had built up so much pressure that gas was spewing out of the cap like a deadly geyser. If you have the stock valve for the dual tnak system, this might have helped ruin the valve, or at least exacerbate the problem.

Even if it is unrelated, if you have the dual tanks, I recommend getting the valve replaced. Ford will do it for free. The problem could obviously be quite dangerous.

Bryan

 

Oh...another possibility, I didn't even think about the purge valve and solenoid. I'm no expert on the emission stuff, and maybe someone else can chime in, but I suppose if the purge valve never opens, the vapor in the canister could build enough pressure to condense into a liquid before finally squirting out of the cannister.

I dunno...maybe wait for one of the crusty veterans to follow up...they might be able to give you a more definite answer!

Bryan

 

it is on the driver side a square box there are 2 caps on top and from what i can see a hose going into it it is towards the front of the fuel filter in a little from the side. its only leaking on and off and this box dealer said was a vapor storage canister
thanks
Mike

 

Yup...your description sounds like the fuel canister...it's a dual chamber canister with a cap on each chamber. I have a 92 F-150 with dual fuel tanks, so my layout is may be a little different.

I checked the repair guides on autozone.com, and there is in fact an orifice on the fuel tank that is supposed to prevent liquids from entering the vapor hose that leads to the canister.

 

sidala-

Did you fix your problem? I am curious to find out what it was....

Bryan