Very frustrated, hoping someone can point me in the right direction

[mrkrsll]

I have a 2008 Tahoe LTZ Flex. 5.3 4x4.

I bought the truck a few years back and right from day one, I have always had issues filling the tank. A CEL came on a while back P0446, an issue with the fuel/evap system. It was around that tie that I started smelling a very strong gas smell from the rear of the truck. I started inspecting the lines coming out of the canister and realized that the evap vent valve and filter were completely clogged. I attempted to clean it out, but gave up and just bough the vent valve, filter and the accompanying hoses.

I changed that out, but still had issues filling the tank. Not only that, but I also discovered a small puddle under the truck that smelt like gas. It seemed asif the leak was on the top of tank so I decided to drop the tank. Once I got the tank out, I noticed that the supply line on the top of the sending unit was rusted and leaking. Bought a new sending unit and fixed that issue. Got the tank back up with the new part in and the smell of gas is now completely gone. CEL is now off and has not been back on.

Filling up the tank is now even worse then it was before. I get about 10 to 20 cents in and it shuts off. takes 5 mins to out 5 bucks of gas in.

Not sure where to look or what to do. I even unplugged lines as I was filling to maybe see if the problem went away and I would find the culprit, but that obviously didn't happen.

Any suggestions?

Thanks!

 

[t.stimpson]

there is the filler neck where the gas pump goes in but there is also another breather tube that comes off of that that vents the tank when filling. As gas goes in the air in the tank needs to escape. Sounds like the vent tube is blocked.

 

[FuzzyChopz]

Same thing happened to me after I replaced my fuel pump. I connected the Evap tube to the plastic connector towards the rear of the vehicle first. Then installed the tank. But you must install the tank and then run the Evap hose over the frame or it will pinch it and make it not work. Reach around over your rear way bar towards the rear of the tank
And see if you feel the connection and see if it is loose.

 

[sumo]

I had similar problem. My lines into he pump rotted. It ended up just dumping fuel on the ground with the key on.

 

[mrkrsll]

Same thing happened to me after I replaced my fuel pump. I connected the Evap tube to the plastic connector towards the rear of the vehicle first. Then installed the tank. But you must install the tank and then run the Evap hose over the frame or it will pinch it and make it not work. Reach around over your rear way bar towards the rear of the tank
And see if you feel the connection and see if it is loose.

View attachment 63913

Thanks so much. Re routed the line above the frame and this fixed the issue.

I am now seeing a few new cel's that were not there prior to changing the sending unit.

P0442 (Leak, could be a few things)
P0455 (Leak, could be a few things)
P069E MIL illumination???

 

[mfrnfyg]

Could be that the sending unit you bough may be faulty.

 

[mrkrsll]

Bump