charcoal canister help
Thread Starter
Intermediate
Joined: Apr 2025
Posts: 32
Likes: 3
From: Canon City, Colorado
charcoal canister help
One of the valves in my charcoal canister (1988 Corvette) has failed some way, and gas fumes are streaming out of the tank around the gas cap once the car is running warm. I cannot buy the whole unit again - at least not a form that looks like what was stock. What is the best solution?
Burning Brakes
Joined: Aug 2008
Posts: 861
Likes: 220
From: Tampa, FL
One of the valves in my charcoal canister (1988 Corvette) has failed some way, and gas fumes are streaming out of the tank around the gas cap once the car is running warm. I cannot buy the whole unit again - at least not a form that looks like what was stock. What is the best solution?
Otherwise, I would also check the vacuum to the cansiter as well to make sure it's actually good.
Melting Slicks
Joined: May 2019
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Likes: 1,390
From: Mid-Atlantic
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Have you inspected the tank itself? There's a couple of places that you really just can't see, even with a flashlight. Particularly the area adjacent to the rear bumper cover.
My tank was rotted and split all the way across, which I only discovered after buying the car when it failed a tank pressure test in the inspection lane. Apparently, the only thing holding fuel in the tank was the bladder. Which itself eventually started to leak. The fumes were really bad and naturally rose upward, giving the illusion that it was coming from the cap.
But, maybe it'll be something simple like a valve.
My tank was rotted and split all the way across, which I only discovered after buying the car when it failed a tank pressure test in the inspection lane. Apparently, the only thing holding fuel in the tank was the bladder. Which itself eventually started to leak. The fumes were really bad and naturally rose upward, giving the illusion that it was coming from the cap.
But, maybe it'll be something simple like a valve.
Last edited by Natty C; Yesterday at 04:30 PM.
Thread Starter
Intermediate
Joined: Apr 2025
Posts: 32
Likes: 3
From: Canon City, Colorado
Thank you for the diagnostic suggestions. I will revisit all of these ideas with my mechanics. All the same, my mechanics and the body shop that removed all of the rear components to repaint the rear bumper/spoiler this week. They inspected the lines, vacuum hose and canister components and function. They looked for other issues and found nothing amiss with the fuel tank. Its that canister unit that requires replacement - so I need the part. Any sources for this part or a substitute that works?
