Evap system?

I have a 99 chevy tahoe i was able to get my inspection sticker last year. this year my check engine light came on and took it to auto zone to put it on the computer. It gives me an OEM Number to cross P1404-0440 which means that my EVAP is troubleshooting. I have replace my gas cap, There is no leaks,I know for sure is not my solenoid. but, can it be my EVAP canister its there a website that i can visit, where it can show me how to check it or how i should be looking for .