EVAP Charcoal Canister Removal Modification

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esoteric_ast

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Gas pump shuts off so many times while filling that I hate pumping gas. Going to have to replace and clean all that crap out. What a junk setup. The vids on youtube show the mess that they make.
 

HACK BLOCK

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I had a similar issue, mine would either fill extra slow or not at all... stopping after a gallon or so. I replaced the entire evap system and gas cap for good measure. Problem solved. I did the work myself, so it wasn't costly. My trucks an '08 with 210k on the clock. Hope that helps you out.


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about how much
 

Big Mama

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If I recall I spent less than $60 and about 30 minutes for all parts. Watch for the adapter for the canister and vent valve. Mine said it didn’t come with it but it did so I have an extra.
 

shartymcqueef

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For some reason I couldn’t find anything on the internet about how to fix this problem at home without buying new parts… so here ya go, hope this helps someone:

 

THarber

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When you tune out the evap error code, all you're doing is eliminating the code, not the problem. If after replacing the canaster, valve and solenoid you still have the problem, look at the top of the gas tank for a collapsed fitting. The only way you can get the tank to fill is the allow the air trapped in the tank to escape. Removing the canister will just allow fuel to spill on the ground when you fill it up. You can remove the evap line from the tank and run a new line up the the top of the filler neck and then cap it off with the same little plastic device that you use on a rear end vent. The only issue is it will always smell like fuel.

Tim
 

Beenrobbed

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Hey guys, I've been having issues with my EVAP system for a while. The issues started with a slow filling fuel tank, and after attempting to fix that a while back... I ended up with a slow filling fuel tank, multiple leaks in the system, along with the occasional "tighten gas cap" message. Long story short, rather than continue down the wormhole to find my original problem, and my new EVAP problems, I had BlackBear performance delete the EVAP system from the computer when I had them do my engine tune.

So I have had no engine lights or issues since having them do that, but my tank still fills slow and I still get the occasional "tighten filler cap". So before it gets painfully cold and I have to stand at the pump to fill up, I thought Id try to see if I can remove or modify the system to vent properly and not throw the loose cap message.

One solution as I understand it is to simply remove the charcoal canister and my fuel tank would fill normally, but would the computer see a low pressure and throw the "tighten fuel cap" message? Could I remove more than just the canister with desirable effects?

After learning more about how the system works, im guessing my original issue was probably the purge valve... If I was to replace the purge valve could I take the line from the tank to the charcoal canister and the line from the canister to the purge valve, and connect them together to bypass the canister and send the gas vapers straight to the stock vent?

I guess when Blackbear "deleted" the EVAP system, they just programmed the computer to never open the EVAP solenoid, so the engine never draws the fumes from the charcoal canister and therefore the OBDII system never sees these pressure issues to throw the engine codes. But the physical pressure blockage still impedes filling up the tank all while the I'm guessing the BCM senses my small leaks in the system and thinks the cap is loose.

I've tried to learn about how the system works and I think I have a general idea, but I wanted to see if anyone else had any insights or experience on how to get the fuel tank to vent effectively and safely? I realize this is not the proper way to fix this issue, but also if I could just get around the slow filling and gas cap dash message then it would be one less system to worry about upkeeping and it would be truly deleted. Making the truck just a little simpler to work on the future.
I have an 05 Yukon denali that i removed all of evap system from. Wondering if you ever completed and if so how it all went for you?
 

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