Fueling problem

[Dan1401]

Have an ‘09 Tahoe that started having trouble filling up. Can hear gurgling sound in the filler neck and only takes $1 or less of fuel at a time. Takes several minutes of removing and replacing the nozzle to fill the tank. Changed the charcoal evap canister and evap solenoid, but still having the same issue. Any thoughts or advice?

 

[gooffeyguy]

Others on here have posted similar problems and usually what happens is pellets from the charcoal cannister get sucked up into the lines. Disconnecting the lines and using compressed air to blow them out usually fixes the problem

 

[Dan1401]

Thanks. Will give that a try. Does it matter which way you blow the lines? Don’t want to create more problems.

 

[Fless]

First thing you may want to do is to find the canister vent valve back by the fuel tank and check it. When replaced these could have the extended filter hose that moves the filter from the OE location in order to minimize dirt clogging.

Or is that the one you meant by the evap solenoid?

 

[Dan1401]

Yes. That’s what I changed along with the charcoal canister. Going to change the purge valve and try blowing out the lines. Charcoal canister was definitely bad. Spilling little pellets everywhere

 

[CrashTestDummy]

Bringing this back up, because it appears we may have fixed the fuel fill issue on our '10 Tahoe. We, at least, have one fill on record with no issues. We'll see how it does next time.

Late last year, the truck started having trouble kicking the fuel nozzle off when trying to fill up. This seemed like a problem at a select few stations, so we opted for other places this didn't seem to be a problem at. Then, around the start of the new year, this started to be a problem everywhere. No matter where we took it, we'd only get about a half-quart of gas in the tank before the nozzle would shut off. No matter how slowly we tried to fill it, the nozzle would still shut off. We replaced the usual suspects, the purge valve and the vapor canister solenoid assembly, with no resolution to the problem.

I came here and discovered there might be a problem with the vapor canister. So I got a new one and when I went to replace it, HUNDREDS of tiny carbon mouse-turds fell out of the hoses when I disconnected them. Still more poured out the canister when I finally dropped it out of the way. I hooked up our Dewalt vacuum cleaner and sucked a lot of the little turds out and put everything back together. No good, as we still couldn't fill the truck.

After finally getting time when both of us aren't on call, we climbed under the truck, disconnected the vapor hose with the white fitting, rigged up a Rube Goldberg contraption with heater hose, the Dewalt vacuum and a fair amount of painter's tape. We turned the vacuum on, and while tapping the hose with the handle of a screw driver up by the fuel tank, got another cup, or so, of carbon turds out of the hose. As we were starting to get high from the smell of fuel vapors, we figured we'd pretty much cleaned the hose out. We were finally able to get the tank filled without the nozzle shutting off until the tank was actually full.

Here's our configuration that worked for us. We did pull the gas cap off to make sure we could flow air from the tank through the evaporator hose, so hopefully we now have it fixed. And, to Dan above, Unless you drop the fuel tank and disconnect the hose at the tank, you're NOT going to 'blow' the lines out. We tried that last time, and got nothing (pressurizing the fuel tank with shop air).

 

[Geotrash]

Bringing this back up, because it appears we may have fixed the fuel fill issue on our '10 Tahoe. We, at least, have one fill on record with no issues. We'll see how it does next time.

Late last year, the truck started having trouble kicking the fuel nozzle off when trying to fill up. This seemed like a problem at a select few stations, so we opted for other places this didn't seem to be a problem at. Then, around the start of the new year, this started to be a problem everywhere. No matter where we took it, we'd only get about a half-quart of gas in the tank before the nozzle would shut off. No matter how slowly we tried to fill it, the nozzle would still shut off. We replaced the usual suspects, the purge valve and the vapor canister solenoid assembly, with no resolution to the problem.

I came here and discovered there might be a problem with the vapor canister. So I got a new one and when I went to replace it, HUNDREDS of tiny carbon mouse-turds fell out of the hoses when I disconnected them. Still more poured out the canister when I finally dropped it out of the way. I hooked up our Dewalt vacuum cleaner and sucked a lot of the little turds out and put everything back together. No good, as we still couldn't fill the truck.

After finally getting time when both of us aren't on call, we climbed under the truck, disconnected the vapor hose with the white fitting, rigged up a Rube Goldberg contraption with heater hose, the Dewalt vacuum and a fair amount of painter's tape. We turned the vacuum on, and while tapping the hose with the handle of a screw driver up by the fuel tank, got another cup, or so, of carbon turds out of the hose. As we were starting to get high from the smell of fuel vapors, we figured we'd pretty much cleaned the hose out. We were finally able to get the tank filled without the nozzle shutting off until the tank was actually full.

Here's our configuration that worked for us. We did pull the gas cap off to make sure we could flow air from the tank through the evaporator hose, so hopefully we now have it fixed. And, to Dan above, Unless you drop the fuel tank and disconnect the hose at the tank, you're NOT going to 'blow' the lines out. We tried that last time, and got nothing (pressurizing the fuel tank with shop air).

View attachment 378625

This makes me very uneasy. Drawing fuel vapors into a vacuum cleaner seems like a recipe for disaster. Any of those fumes make it anywhere near the motor and you're going to have an explosion.

 

[CrashTestDummy]

We were outside and I'm sure the vacuum pulled across the air filter in the vacuum kept the AFR too low to be flammable. Being a brushless motor, the possibility of generating a spark is low, too.

 

[CrashTestDummy]

Note that when I was out in the shop the other day, I still had the old purge valve laying on the counter. Since the new one I installed last month worked fine with no codes, I figured I'd never use the old one again, so picked it up to throw away. I gave it a shake, and could hear something rattling around inside it. I turned the two hose nipples down and out of one end came yet more of those confounded carbon rat turds!! That cr@p gets everywhere!!