P0455 and gas tank gurgle

Mounce

Well-Known Member
So, have been having issues with filling the tank, have to trickle gas to fill it, too much and it kicks off. Typical.

Started by removing vent valve, observing that it wasn't blocked, blew dirt out of it with compressor and blew out the vent line with the gas cap off to prevent possible pressurization of tank. Wanted to check the charcoal canister to see if its flooded or something but it's mounted atop the tank on the EXT's.

A week or so has passed and it set a p0455 today and now has an audible gurgle from the tank in the general vicinity of where the fuel pump can be heard the loudest. Can't hear it through the filler tube though. Covered vent valve with thumb to stop any possible air flow and gurgle persisted.

Any ideas? Charcoal canister is officially flooded and i'm hearing the gurgle from it? Fuel vaporizing/evaporation/building pressure inside showed up as a evap leak thus the code?

sidenote: gurgle is not present when only priming the pump, it can only be heard while running.
 
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Mounce

Mounce

Well-Known Member
Total fuel trim peaking around -16 which I feel further solidifies my assumption with the charcoal canister. Excess fuel vapor entering engine.
 

Mooseman

Moderator
Agreed. Just sucks that it's on top of the tank just to check it. How much does it cost? Might be worth it just to replace it.

The evap leak though may be something else. Check the hoses and stuff on top while the tank is down. Something else may be at play.
 
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Mounce

Mounce

Well-Known Member
They're in the $100 ball park when I glanced on Amazon, didn't even verify part numbers. Cleared light, will dig deeper when it comes back on and once I have parts on hand and all.

Tank was replaced a couple years ago under recall so hopefully there's no lines rubbing where they shouldn't be or anything.

I figure I'll replace the canister and do the ol' visual inspection for evap leaks and call it good. If evap code returns after repair I'll nab the smoke machine from work and find it.
 

MRRSM

Lifetime VIP Supporter
The same VOP (Video Original Poster) created these two Videos on Cleaning out the Charcoal Canister(s) from Excessive Atmospheric Dust and Dirt Ingestion that is causing the Fuel Vapor Back Pressure resisting the In-Flow of Fresh Fuel.

IIANM, You truck is an Earlier Model (assuming the White Truck is the one with this problem) than the ones shown in this Video and even of the Charcoal Canister is mounted atop the Fuel Tank... the principles are the same.

If you can access the In-Out Lines shown in this Video... you might be able to clean the Canister out in place using Compressed Air, a Face Mask and some Eye Protection versus using the novel R&R Water Cleaning Method as being a bit too cumbersome:


 
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Mounce

Mounce

Well-Known Member
It's actually on mom's 04 trailblazer but same design overall. I'll look into that, thanks.
 

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