That’s not what I find on the internet. This is;
P0441 Code - Toyota. The P0441 OBD-II code is relatively rare (at least for Toyotas). It indicates an Evaporative Emission Control System Incorrect Purge Flow. The EVAP system manages gasoline vapor evaporation from the gas tank and fuel systems.
So, in other words, not just a gas cap.
And a P0446 is;
P0446 Code - Toyota. The P0446 OBD-II code often triggers with other related EVAP codes (like P0441), and the specific combination of codes can give your mechanic a better idea of where the actual problem lies. Specifically, P0446 indicates an Evaporative Emission Control (EVAP) system vent control circuit malfunction.
You might start by watching this;