2007 Suburban fuel fill

[stocksj]

I my new to me 2007 Suburban, I’ve notices the last 2 times I’ve tried to fuel up that the back pressure only allows me to get about 8oz of gas in at a time before shutting off the fuel filler. Taking forever to gas up. What could be causing this?
Thanks

 

[Fless]

Indicative of a vent blockage, whether that's the canister vent valve back by the tank, or the canister itself, or evap lines are plugged with charcoal pellets from the canister. You might have an evap code stored. First thing I'd do is see if the canister vent valve is working properly. With no voltage applied (as in key off or connector pulled) you should be able to blow air through it. Applying 12v to it should close it. Repeat in succession to eliminate an intermittent valve. It may have a remote air filter so be sure to check that, too, for blockage.

If that's not the problem then it will be time to dig deeper into the evap system. There are many threads on here about solutions.

Eric shows what the vent valve looks like at about 1:25 or so, and also shows some diag procedures.

 

[stocksj]

Today I got out the air compressor and a small nozzle. I blew out what looked like 2 small vent holes and then added 2 x 5 gallons of gas from some canisters. Worked like a charm! Thanks for he tip, saved some $$$$$

 

[stocksj]

Today I got out the air compressor and a small nozzle. I blew out what looked like 2 small vent holes and then added 2 x 5 gallons of gas from some canisters. Worked like a charm! Thanks for he tip, saved some $$$$$

This past weekend thinking I had the issue fixed I tried to fill up and same problem. What I may need to do until I replace the vent line is use a gas funnel and fill up that way since it doesn’t create any back pressure in the vent line. It’s a learning process.