musky hunter 67

I have a 2007 5.3 liter 1500 LTZ Suburban. I have had an issue on filling up the fuel tank for several months. I have recently replaced the fuel vent solenoid and the carbon filter canister under the vehicle. The problem persists as it doesn't matter what rate of fuel is being pumped into the vehicle, only about 1-2 gallons before it will trigger the shut off of the handle on the pump. Even trying to fill slower than the first click on the handle it will backflow up the fill tube and shut off the pump. I'm clueless as to what else could cause this problem. Any advice or help would be greatly appreciated.

mulmur1

It sounds like the vent line is blocked. There was a GM bulletin noting that the vent line should be replaced with 5/8 rubber line and relocated. You want to relocate the line higher on the vehicle, so that it doesn't get full of mud and moisture. Some people are relocating the end up over the transmission.

Good luck with the repair.

cleveland63b

if you replaced the vent solenoid and canister and it didnt fix then you need to check the lines between the tank and canister and canister to the vent solenoid...theres a clog somewhere

or try a different gas pump if you use the same 1, in rare cases the pump has been a problem

musky hunter 67

I've used many different gas pumps so that is not the answer. there are three lines under the car going to the canister which was replaced Saturday, one is the solenoid vent tube that was replaced last Saturday, what are the other two lines and how do you check if there is a clog in them? the lines are hard plastic and are not kinked. I was told that there could be a ball that is in one of the lines or gas tank that in case of rollover prevents the fuel from spilling out.

musky hunter 67

As stated I replaced the fuel vent solenoid so that is not the reason for the blockage. any other ideas would be helpful. I'm trying to avoid dropping the tank and doing a full blown inspection but that might be the next course of action.

mulmur1

Please find attached an image of the fuel system for your truck. I would take a look at item #14. This is the vent hose. It may be plugged and this is causing the problem. You have replaced a lot of parts and it gets frustrating.

Hopefully you can figure it out soon.

musky hunter 67

If 14 is part of the fuel vent solenoid the entire unit was replaced from the canister to vent, as it came as one whole unit. there are two lines towards the back of the canister that I am unsure of. We did a smoke test on the gas tank and we had no smoke coming out of the fuel vent by the fuel fill, the solenoid was open according to the evap test so we thought the fuel vent solenoid was stuck closed. That is why we replaced it, we checked it after replacement and found it was not faulty, we then replaced the carbon filter canister thinking that must have been were the blockage was coming from. that is not the problem as the fuel filling still persisted and there are no codes being sent from the computer. I will put it up on a lift tomorrow and check all lines going to the canister to see if any are blocked.

mulmur1

Part #14 is a vent line that runs off the filler neck. You can see in the image where it attaches to the filler neck. It is a rubber line. When you have it on the hoist, take look at the line and see how it looks. Unfortunately, if it is blocked, it will cause the problems you have noted.

Hopefully this is the solution.

musky hunter 67

We finally got the truck back on a lift, performed another smoke test, results no blockages all vents open and performing normally. Inspected all areas of fuel filling lines, found no obstructions even took everything apart to inspect the screen in the line it is clear. Still having same problems with filling up although I was able to get 3.5 gallons in the tank before it shut off. I will be checking with Chevy if they are any updates as other people with similar models are having the same problem filling up.

Nickted

I have 07 suburban with the same exact problem. It doesn't happen every time but it happens a lot. I was at the pump about a month ago and some guy was asking me if I had that problem. I told him I did as he could see about every 2 gallons the pump would shut off. He told me that he had an older suburban that did the same thing. Then he told me to hold pressure on the nozzle. He said something about the pump was not sealing properly to my car. So now every time I feel my Burb I just hold it in with my elbow. This has seemed to remedy my problem. I know this isn't a fix but its better than starting the pump every couple of gallons.