Code P0440

[camjamb]

A while back my 2002 Tahoe's check engine light came on and showed code P0440. My only sympton has been the gas tank not venting. I can hear the pressure releasing when I loosen the gas cap. Doing a search I think I have it narrowed down to either a purge valve, or a fuel tank pressure sensor. Anyone had this problem before and how hard is it to fix?
Thanks

 

[camjamb]

Changed the purge valve and it seems to be fixed if anyone has the same problem.

 

[thzpcs]

Glad to hear you got it fixed!

 

[corvette89]

going crazy

I also had a filling problem on my 2005 . Replaced vent solenoid and purge valve with no luck. Took both of them completely off and wont take gas. Can blow air through all lines. What to do.......