Hi folks,

i have the dreaded P0440, P0441, and P0446 codes. I’ve noticed a gasoline smell in the rear driver side wheel well for a few hundred miles and assumed it’s from a rusted filler neck. Haven’t diagnosed it yet, but I have not had any codes until yesterday. Gas cap is good. It’s taken a while for the EVAP test to run, but now that it has these codes shows up. Could a perforated filler neck cause these codes alone?
Also I should mention that I have a rough idle at 1500 RPM on a cold start. Idles smoothly below 1000 and runs very well after it warms up a bit.

 

Here is a post from some years back: https://www.clublexus.com/forums/es-...-canister.html

TL;DR I wound up replacing the entire charcoal canister. In my case, it cured the problem. Hope that helps,