Removing Charcoal Canister

[93SierraWT]

I've been cleaning/decluttering my engine bay and I'd like to delete my charcoal canister. Has anyone ever done this on a GMT400? Would this have any bad effects? If anyone has a write up on this it'd be great. My truck is a 93 with a 4.3 Vortec.

 

[JJZ71]

I wanted to do this to make room for a second battery tray in my truck and I was told not to take it out because of fumes.

 

[woody80z28]

I got rid of the one in my Camaro, but will be reinstalling it at some point. It's there for a reason.

 

[shortchevy]

Ive done this on my Jetta, all charcoal systems are the same... the gas tank builds enough pressure to open some kind of "purge valve" which purges, if you will, into the intake to be burned off instead of just releasing it into the air, the charcoal canister is between the gas tank and the intake/TB. what I did was
-plug the line that goes into the intake (I jammed some quicksteel into the hole on my TB)
-find the vent hose on gas tank cut and cap it.
-PUT A VENTED GAS CAP ON, if you dont pressure will build in your gas tank and you dont want that


now Im not 100% sure on cel problems on a gmt400... my Jetta when done only threw the code for the purge valve.

 

[woody80z28]

I installed a vented cap and pressure still builds unless I leave it loose. I was told vented caps only let air in, not out.

 

[ndians68]

the one on our 88 wasnt hooked up until about 4wks ago

 

[FastOrange]

i took mine off, dont smell any fumes or anything...

 

[shortchevy]

I installed a vented cap and pressure still builds unless I leave it loose. I was told vented caps only let air in, not out.

Im sorry for my wording... by vented gas cap I ment a gas cap with a whole drilled in it

 

[MOBS]

The old style vented caps is same as what shortchevy is talking about, on the older cars before charcoal canisters. When you remove the cap, it has a few small holes in middle with a diaphragm that moves up and down depending on pressure or suction. When the pressure reaches a certain point it pushes the diaphragm up and past a vent passage in the side of the cap letting air escape; when the suction reaches a certain point, it pulls diaphragm down past another passage that lets air in. True a hole in the cap will also work, but it can also cause gas to spittle out or dust to get in. Best thing to do is just run the old style vent hose that mounts in the gas filler neck, and sticking a little push-in breather or fuel filter into the end of the hose will keep dirt dobbers from clogging it up.

 

[MOBS]

The cheap aftermarket types also had a diaphragm, worked a little differently though. Diaphragm was mounted on the center stud of cap, edges of diaphragm rode in a cylinder shaped surface on inside of cap. The ring(grip/edge) of cap was vented. When the pressure pushed up on diaphragm, it would make the edge of diaphragm pull away from "cylinder wall" and let air out, suction worked same way, except letting air in. The most common style was the smooth chrome caps, which were annoying at best, because anyone with skin oil couldn't get a grip on them.