2008 Yukon gas tank issue.

[Summer b]

I am unable to fill my gas tank. It pretty much overflows within seconds. this started a month or so ago with it just clicking off like it was full and its slowly progressed to almost unable to get a dollars worth in with a gas can! No rough idle no check engine light either. Any help would be greatly appreciated. 2008 Yukon 5.3 ltr

 

[B-train]

Probably the purge solenoid under the hood by the intake. Do yourself a favor and buy only GM parts. Or, it could be the charcoal canister let loose and filled the lines with little pellets. Do you electrical tests first. You can also remove the solenoid and let it vent to atmosphere if you are mechanically inclined to do so, I'd just do the test on a cold engine.

 

[Sam Harris]

Yup. The ventilation of the tank is either blocked (charcoal pellets in the lines) or one of the valves is not functioning. If you (or a previous owner) has a habit of filling past the point the pump shuts off while fueling, this will cause fuel to enter the charcoal canister, and eventually, the pellets make their way out the lines, blocking them off.

 

[Fless]

The purge valve on the engine has nothing to do with filling the truck, so look to the rest of the evap system. A purge valve staying open (incorrectly) could cause a hard start after filling, due to fuel fumes being allowed to enter the intake manifold.

Fueling should be done with the truck engine off so the canister vent valve is open to, well, vent. If anything blocks the vent lines, then the fuel won't fill easily. Overfilling can flood the evap canister, block it, and loosen the charcoal bits to spread into the evap lines.

Lots of YouTube videos on evap system diagnostics. Search the forums here on TYF; if you need some links, yell!

 

[89Suburban]

I would think a failed valve would trigger a CEL light but I could be wrong. When my rear vent hose/valve thing-a-ma-bob went bad it threw the CEL and stored a code.

 

[MassHoe04]

I would think a failed valve would trigger a CEL light but I could be wrong. When my rear vent hose/valve thing-a-ma-bob went bad it threw the CEL and stored a code.

I got a code/CEL a few months back.

This is what I got when my purge valve was not working. I believe it was sticking in the open position and threw this code when it happened.

I agree that issue on this thread is not a purge issue, but a vent issue. Vent tubes between the filler and the tank would be my first suspect to check out, then the charcoal canister followed by vent valve.

 

[Summer b]

The purge valve on the engine has nothing to do with filling the truck, so look to the rest of the evap system. A purge valve staying open (incorrectly) could cause a hard start after filling, due to fuel fumes being allowed to enter the intake manifold.

Fueling should be done with the truck engine off so the canister vent valve is open to, well, vent. If anything blocks the vent lines, then the fuel won't fill easily. Overfilling can flood the evap canister, block it, and loosen the charcoal bits to spread into the evap lines.

Lots of YouTube videos on evap system diagnostics. Search the forums here on TYF; if you need some links, yell!

Yes please send me some links! Thanks!

 

[Summer b]

I would think a failed valve would trigger a CEL light but I could be wrong. When my rear vent hose/valve thing-a-ma-bob went bad it threw the CEL and stored a code.

Only thing scanner said was routine maintenance almost due!!!

 

[Fless]

Here are a few for starters:

The Car Doctor
Vent solenoid replacement

WatchWesWork
Evap canister testing (0:00-5:15 min, then 11:00-13:15)

1A Auto

I'm sure that Eric O at South Main Auto on YouTube has a few, too. Let's hope you don't have to blow out any lines, but that's also a possibility.

 

[89Suburban]

Here are a few for starters:

The Car Doctor
Vent solenoid replacement

WatchWesWork
Evap canister testing (0:00-5:15 min, then 11:00-13:15)

1A Auto

I'm sure that Eric O at South Main Auto on YouTube has a few, too. Let's hope you don't have to blow out any lines, but that's also a possibility.

Love the Car Doc and 1A.

 

[B-train]

Just a question, do you shut off your truck while fueling up or leave it running?

 

[Summer b]

Just a question, do you shut off your truck while fueling up or leave it running?

No I do not.

 

[Sam Harris]

No I do not.

You don’t shut it off..?

 

[Fless]

Perhaps I'm misunderstanding the comment "no I do not." Do not leave it running, or do not shut it off?

The canister vent valve is commanded open when the truck is shut off, so it may be staying closed while you fuel. That might be the only problem with the venting. But maybe not. All you can do is try fueling with the truck shut off.

 

[iamdub]

I am unable to fill my gas tank. It pretty much overflows within seconds. this started a month or so ago with it just clicking off like it was full and its slowly progressed to almost unable to get a dollars worth in with a gas can! No rough idle no check engine light either. Any help would be greatly appreciated. 2008 Yukon 5.3 ltr

Simplify it like this: The tank needs to vent, and it vents into the charcoal ("EVAP") canister. The EVAP canister vents into the engine. Find out why the tank isn't venting. A quick test is to disconnect the largest hose on the canister. I think it's the center one. If you can fill up with no problems, then the canister is clogged. If the problem persists, the issue is before the canister, so in that hose or the tank itself.

With it progressing over time, it's likely the canister or its venting system (the purge circuit) is clogged. There's a high point vent hose that runs parallel to the filler tube. Dirt daubers have been known to block that. So, when you slide underneath to disconnect that largest hose, check that vent hose that's zip-tied to the filler tube.

 

[B-train]

No I do not.

Good man. Screw that fear mongering BS. Leave an engine run. I can't count the number of failed fuel pumps I replaced due to "fueling engine off" over the years. Shock a hot motor with cold fuel and find your weak point.....

 

[B-train]

I never shut it off.......and I use my cell phone like a Bad ass

 

[swathdiver]

Dirt daubers have been known to block that.

We got Mud Daubers here in Florida, not Dirt Daubers! LOL

I never shut it off.......and I use my cell phone like a Bad ass

Me neither, can count on two hands with fingers not used how many times I've shut the motor off while refueling and it was always to check the oil.

When a pump starts clicking and doesn't put fuel in my tank, I go to another pump or gas station.

 

[iamdub]

We got Mud Daubers here in Florida, not Dirt Daubers! LOL

I just looked it up and my mind is blown. "Mud dauber" is the proper name! Everything I've ever known is a lie!

 

[Summer b]

No I do not.

I do not leave it running.