Problem fixed: no more CELs, Codes or Permanent Codes, no more near-stalling after fill-up.
Here's my experience. See Post 23 above for background.
After that post, I started getting CELs and codes 0456 and 1450 more often. I do not "top off", and I wait 30 seconds before removing the nozzle. One day, the car wouldn't fire up at the pump. After about 2 minutes of trying it finally started. (I noticed that when I would hold the start button down to keep cranking the starter, the starter would keep cranking after I released the button. Pressing the button again would stop the starter from cranking. I guess you're probably not supposed to hold the starter down? Another rabbit hole?)
I don't like the "throwing parts at it" method, but there are so many possible things that could be bad in the EVAP system (and even with my FORScan I couldn't narrow it down) so...I went with the evap purge valve. There's one at the canister itself, and one in the engine bay. Based on the posts here, I went with the one in the engine bay. Then there's the question about the part number. The parts diagrams all gave me the
d2bz9c047e, but that had more tubes and connectors than the part in my car. Mine looked like
f2bz9c047c, with the single offshoot from the main tubing/valve, so I went with that. Compare yours to the two options before ordering. I got an OEM part from Ebay with free shipping to Maui.
View attachment 56461
After installation, no more CELs, and the 0456 Permanent Code went away after a few stop/start cycles and miles. The 1450 Permanent Code remained until after the first time I filled up, then went away.
Hopefully this will last, but for next time I bought some fuel line (5/16 i.d.) that fits nicely over the valve's tubing nipples and over the tubing. I can cut out the bad valve and just replace that ($27), clamped into the fuel line "adapters".