EVAP system issue.

Hi everyone,

I have been having an issue with my EVAP system for a while. My check engine light (CEL) came on, I had it checked and got P0440 and P0442 codes. I replaced the gas cap with an aftermarket one from Advance Auto Parts. CEL went off after driving a few miles. Three months later it came back on. Did a lot of research and replaced it with OEM gas cap I got from Toyota dealer. CEL went off again, but came back on after running through about two tanks of gas. Checked the codes again, same thing.

I have not done a smoke test, as I hate taking my car to the shop.

I have also noticed that there is gas in the gas filler tube and on the gas cap.

I know that there are a lot of threads on this but I have not been able to find an answer. Can anyone help me in diagnose my problem? Thank you.

 

Charcoal canister may need replacement.

 

That's what I am worried about.

 

Do you have a history of topping off when you fill up for gas?

 

I used to do one extra pull to make sure that it stopped because the tank was full, and not because of a over sensitive sensor. I have stopped doing that since I did my research on my problem.

 

Anyone know what could be causing the fuel in the filler tube?