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.

 

[stocksj]

Update and more woes. about 4 weeks ago on the way home from work I lost power and my engine shut off on the freeway. I pulled over and tried to restart but the engine would not fire. After changing the battery and getting it towed to my local shop I found out that the fuel pump relay was bad. This was replaced along with other parts and all was fine. about a week later after taking a short drive the engine had problems starting. THis time it was the engine crankcase sensor. During the 18 months I've owned this SUV I was using a engine device which disabled the V8 to V4 mode (AFM?). I didn't reinstall the disabler and after a short trip yesterday the engine won't turn over. I was getting the usual vibrations when slowing down going through the gears from 2nd to first. Could my engine be done? Maybe seized? Need ideas, thanks

 

[rmaker]

Sounds like you have several related/unrelated issues. I can only really speak to the fuel fill problem.

Did you have any codes associated with the most recent loss of power?
When you say it won't turn over - does it crank but not fire?



RE the fuel filling - I am in the middle of curing this problem on my 2011 Suburban. I started with the cheapest most accessible parts first (hoping it would prevent to inevitable). I began with the Vapor Canister Vent Valve in the rear, then I changed out the EVAP Purge Valve Solenoid in the engine bay (the hose leading to that crumbled and I had to replace that too), last weekend I swapped out the charcoal canister. Went to pump gas today and no improvement. The lines are packed full of charcoal pellets. I just ordered a new EVAP Line/hose assembly and since the tank is coming down I picked up a new fuel pump. The local shop will do the installation for $350 in labor.

RE the AFM Disabler - I chose to go with a tune to disable the AFM/DOD. Only been a month or so since I had it done, but no issues so far. Did you reinstall the disabler?

 

[stocksj]

I had a disabler on it until after the fuel pump replacement. There are no codes and the engine won’t crank or turn over. I’ll take a look at it this weekend and see if I have any better luck.

 

[stocksj]

I had a disabler on it until after the fuel pump replacement. There are no codes and the engine won’t crank or turn over. I’ll take a look at it this weekend and see if I have any better luck.

Good news, after more research I figured it would be my fuel pump relay fuse so I changed it out yesterday, still no start up . So I pushed down on every fuse and relay in the fuse box to make sure everything is seated. The SUV then fired up. Felling much better and learned something. Not sure why a fuse would be loose as I don't drive on rough roads. I did notice some of the square fuses had the top of the fuse busted off. The contacts in the fuse are still good but I'll replace them anyway. anyway, I'm running again.