2001 Prius: p0440, p0441, p0446

Hello. I recently picked up a 2001 Prius to learn more about it. I've been trying to resolve the following codes: p0440, p0441, p0446. I used a new OEM gas cap & did a smoke test and smoke is coming out of the perimeter of the filler mouth and what seems to be a plastic ring with slots around the mouth.

My question is this:

1. Is this normal?
2. Does this indicate that the filler neck is bad?
3. Does this indicate that the charcoal canister is bad?
4. A bad VSV by charcoal canister?
5. Is it something else?

 

Thanks Patrick, I looked at that prior to posting. I do have a related question being a Prius newbie.

When you unscrew your prius gas cap does it make a sucking sound? (this will help trace the leak as mine does not).

 

Update:

I performed an evap test from the scan tool with the engine running and it indicates that the initial vapor pressure reading is the same as atmosphere (this indicate a leak as I am assuming that there should always be pressure or vacuum in the tank).

As the test continues I can see the pressure change as the VSV's open and close. So this rules out the pressure sensor being bad.

What I need to do now is to check the tank and line going to the fuel filler neck.

 

Went to a dealership in CT and bought another Prius. This time 2003 and did the evap test with the scan tool and the initial reading says the same thing as the 2001 Prius where it says, "initial vapor pressure reading is the same as atmosphere."

I am wondering if this is normal or if it is a common problem for the 2001-20003's. Can anyone shed some light on this?

 

Thanks, but the cat is fine. I've narrowed it down to a leak in the tank, CCV or filler neck. Just haven't had time to take a closer look (school first. lol).