Hello,
I have an 89 4runner 3.0 and now that it's been warm a few day I noticed that my gas tank is building pressure and the vent hose on the charcoal canisters even produced drips. Is something hooked up wrong or what? Has anyone heard of this and know how to fix it. Any thoughts or pointers would be greatly appreciated.

Thanks, John

 

The gas tank vents out the charcoal cannister vent hose in the frame if it cannot vent properly out the filler neck hose/vent. Sounds like you got something clogged or pinched perhaps.

 

And it can also happen from overfilling the tank when you gas up.

 

Thanks for the fast response.... some day I'll contribute rather than just ask questions.

The hose to the tank seems to be clogged if I blow in it... should I use an air compressor?

The other line is labeled purge... what is it connected to (I know it has initials)

something on the back of the intake. What part of the tree should it be hooked into? The top port or bottom?

I should mention that I rebuilt the motor myself and I replaced the tree thing with an old one becaus I broke the original...

almost 7000 miles on the rebuild: and one 600 mile road trip but that was this winter and these are the first real warm days.

 

this happed to me at one time. i had literaly just replaced my fuel cap and drove home from the parts store.. got home and it was puking fuel out of the charcoal canister.. so i though HMMM, the only thing i changed was the cap.. so i poped the cap off and heard and felt a purge of air.. turns out the idiot at the parts store gave me a unvented cap and it built pressure up from the expading air and fumes so it was just pushing it out of the canister vent. maybe you have a clogged up cap

 

The tree thing is the BVSV and was the hoses were hook wrong. I switched them and I'll see what happens tomorrow. The vent tube allows a little air through if continuous pressure is applied.

Incase someone else is trouble shooting this... here is a page where this has been discussed as well
Here

 

It's fixed... I guess I figured it out. Thanks for the direction.

After I installed the motor I had a gas leak on the fuel rail and I was sick of working on it so i took it to my wife's work (a garage) and paid them to fix it at my clubhouse rate. They hooked the bvsv up last because they broke and replaced it while doing the other work.

I guess I'll be the only one to work on my ride from here on out... but $20 per hour is hard to pass up.

I wonder if I'll get better gas mileage now.

 

My vent tube (the one coming out the bottom) of my charcoal canister is clogged... I am assuming by this post that it needs to be funtional??? I have high CO levels during my failed emissions testing and trying to correct it.. Does that vent tube just hang down there? Can I cut off the clogged portion or does it need to be as long as it is and make it to the frame?

thanks guys...getting closer
Neal

 

Yes, the vent line needs to be clear, that is what lets fresh air enter the cannister as the engine tries to suck the gasoline vapor out. Might try pulling that line off and blow some compressed air through it. I think it is stuffed into the frame rail in order to keep the line from flopping around and also gives it a somewhat clean place to pull fresh air from.

 

thanks 4crawler.. I pm'ed you, please let me know your opinion on a couple other topics... I will check that hose tonight and make sure its functional...

Neal