New to site. I am John. I have a 2000 Silverado 1500 4.3 5 speed. A couple of months ago the battery dies abruptly and without warning. I have had problems with gas gauge since I got truck a couple months ago and PO says it had been like that for a while. Ran fine and we just used mileage to know when we needed fuel, as it is a work truck. So, my wife thought she had ran it out of gas. We tried to add some and it kept turning off like it was full. I discovered it was the battery and replaced it. It started and runs fine but still want allow fill up. I have tried several gas stations and filling it slow but no luck. I checked online, including here and see EVAP is usually the problem. I have checked the computer and it wouldn't read (no power). Replaced the fuse and I have no codes. I disconnected the purge valve, checked and it has 12 volts and clicks when power is applied as does the vent valve. I took canister loose and nothing loose or falling out of it and air passes through it and all hoses. I read that you could leave the switch on and if it was the vent valve it should fill. It did not, not even with engine running. I disconnected air line to vent valve and removed the value completely from the truck and it will still not allow a fill up.
I do not want to just replace parts until I find it. I know sending unit needs to be replaced to fix fuel gauge but this was not causing a problem with the fill ups and don't see how it could have just started now. Please help.

 

Welcome to the forum , going to move your post from the new member area to the truck section so that other forum members can chime in...

 

Not heard anything from anyone on this yet. So I was driving truck with EVAP solenoid disconnected. Finally got code, 0440, I Believe. Went on and bought new Solenoid and installed. Code reset in a few minutes. However, it will still not allow me to fill it up.
Still looking for an answer.

 

Still looking for some help

 

The tank is not venting that is why its not filling, I'd get under the truck and inspect the filler neck and the vent hose(s) for any kinks. Do you happen to live in an area with mud daubers?

 

If you were not getting any codes prior to the filling up issues I would be concerned you may have some blockage in the fuel filler neck and or vent tube...
You may need to remove the filler hose to make sure there is no blockage...
give this a read.... attached