[Bee75]

Hi guys,
My check engine light keeps coming on with the P0446 code and lately I’ve been having trouble putting gas in the tank without the pump shutting off over and over. I ca he’s out the gas cap with a new one from GM and I replaced the vent valve solenoid on top of the gas tank. The only thing left is the charcoal canister I’m assuming.
I was given some information a while back from a fanatic regarding a service bulletin that dealt with a crack in the fuel filler tube/neck that was good for 150,000 miles or 15 years. Has anyone had this repair done?
In the meantime, does anyone have any tips as to how to diagnose this code?
Thanks so much.

Brian

 

[Texasbaehr]

If you replaced the vent valve solenoid and gas cap then it may be the filler neck issue or charcoal canister. Dealer will repair the filler neck under the extended warranty if you are within the limits.
Outside issue can also be the fuel sending unit gasket or cracked hose but you would have a noticible gas smell if parked in garage if one of those were the issue.

 

[nj6969]

I think there is also some type of Vent Valve on the Intake. That was the problem on my '06 Silverado.

Nick

 

[moscooter]

:|
I've had to deal with that problem twice on my Avalanche. Replaced the item on top of tank and that solved it the first time. Last time, new cap, plus tank top item plus under hood valve item did not stop the code from coming back.

You may end up having to have a "smoke test" performed to isolate the leak. Mine was leaking on top of tank. This required removing the tank which showed that squirrels had chewed thru my vent line.:surprise: An expensive venture.:frown2:

 

[VEGASSR]

Can anyone direct me to more information on the Service Bulletin that dealt with a crack in the fuel filler tube/neck that was good for 150,000 miles or 15 years please?

Thanks in advance.

Chuck

 

[snomuncher]

Cracked Fuel Tank Inlet Check Valve

Can anyone direct me to more information on the Service Bulletin that dealt with a crack in the fuel filler tube/neck that was good for 150,000 miles or 15 years please?

Thanks in advance.

Chuck

Check These Links:

https://www.ssrfanatic.com/forum/f5/2004-recall-notice-152578/

https://www.ssrfanatic.com/forum/f5/evap-code-p0449-help-195290/#post3292938