Getting message?:"Tighten Gas Cap" or are you Unable to fill your tank? ! Look here !

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dantheman

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so we went to fill it up again on saturday and same problem with the pump clicking off.

learn from my mistake and dont think you can just disconnect a few lines while the tank is lowered without disconnecting everything. just take it all the way out the first time and clean the hoses.

wife and i did that sunday. dropped it out, blew out all the lines (and got a LOT of charcoal out again) until they were flowing substantial air out. reinstalled and it filled up like a dream.

what an annoying problem.
 

Nate7326

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I have an 05 Cadillac Escalade. First issue I noticed was the pump stopping and not being able to fill the gas tank. Next I had the check engine light come on. I then replaced the purge valve and the evap canister. The check engine light went off, but the filling problem continued. I then got an alert on the display panel to tighten the fuel cap. I changed the canister solenoid next and I'm still having the issue. I have not actually checked the gas cap itself yet. From what I've read, I thought the problem would be one of the parts I've replaced but I haven't had any luck yet. Help please!!
 

clandr1

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I have an 05 Cadillac Escalade. First issue I noticed was the pump stopping and not being able to fill the gas tank. Next I had the check engine light come on. I then replaced the purge valve and the evap canister. The check engine light went off, but the filling problem continued. I then got an alert on the display panel to tighten the fuel cap. I changed the canister solenoid next and I'm still having the issue. I have not actually checked the gas cap itself yet. From what I've read, I thought the problem would be one of the parts I've replaced but I haven't had any luck yet. Help please!!

I've done the same thing as you with the same result at most pumps, however there are some pumps that I use that have no trouble filling up without clicking off. I've just chalked it up to a redesign in pumps over the last 13 years I've owned my truck.
 

Fless

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For anyone looking for help with these problems in the future, this should help:

Hack job. Fix it right by diagnosing and using functional parts. It's a simple system and isn't all that tough to make work correctly.

As I posted in response to your other multiple posts of this, it's one cause among many. If the pellets have migrated into the evap lines, to the purge solenoid or the vent valve, you'll have more work to do.
 

shartymcqueef

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Hack job. Fix it right by diagnosing and using functional parts. It's a simple system and isn't all that tough to make work correctly.

As I posted in response to your other multiple posts of this, it's one cause among many. If the pellets have migrated into the evap lines, to the purge solenoid or the vent valve, you'll have more work to do.
Hack job? Lmao! This is GM asking people to waste money for no reason. It’s a GAS TANK VENT. Same concept as on your red can for the mower or any other gas tank!

GM wants to muddy the water so rubes will waste money to “do it right” when all you need is a clean and clear vent from the tank to the atmosphere.

Anyone saying otherwise… rube
 

ivin74

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Hack job? Lmao! This is GM asking people to waste money for no reason. It’s a GAS TANK VENT. Same concept as on your red can for the mower or any other gas tank!

GM wants to muddy the water so rubes will waste money to “do it right” when all you need is a clean and clear vent from the tank to the atmosphere.

Anyone saying otherwise… rube
It's not GM, it's the EPA that put those regulations in place. The carbon canister is there to kept the gas fumes from going to the atmosphere. If you delete the carbon from the canister, the vehicle will be smelling like gas all the time.

I did that to a ford Taurus and after about 2 days of smelling gas I purchase the canister and left the sht alone.
 

Blk00ss

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I realize this is an old yet ongoing thread. I thought I'd list my experience in case anyone runs across this.

Our 2005 Tahoe with roughly 160K (at the time) started having fuel filling issues. if you tried to lock the handle it would either shut off, or spill gas everywehere. We would sometimes get the "tighten gas cap" message as well. But sometimes it would go days and days without displaying that message. We also never once had a code. Just slow fill and occasional tighten gas cap message. So I replaced the solenoid...didn't work. Started researching, watching YT videos etc and found many people talking about vent lines and them becoming clogged with charcoal pellets which keeps the tank from releasing pressure as you fill. So I disconnected the line with the white clip going from the tank to the evap canister and sure enough, tons of pellets fell all over the floor. That's actually the only line I could get free, but I knew right away what the issue was. I tried hooking a shop vac to that line to suck out while someone up top opened and closed the gas cap to allow the fuel tank to expand and contract. This removed some pellets, but issue was still there. So, I was prepared to drop the tank, but then I found a guy in the comments of a YT video that said he didn't drop his tank at all. He simply disconnected the lines to the evap canister and stuck the tip of his leaf blower into the gas fill tube, and turned it on. He said pellets flew out all over the ground and issue was resolved. Reading that I decided to take a funnel, cut the end off to open the hole up a bit bigger (more velocity) and stuck it into the gas fill tube. Took my shop vac on exhaust side (cleaned it out of course) and blew into the funnel. Pellets came out everywhere. Went to get gas, filled up faster than it ever has. We still get an occasional "tighten gas cap" message, but the truck has been driven mayb an hour since I did all of this. Not sure if that'll go away after driving it more, like a code does. But this issue was resolved fairly easily with this method.
 
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