Okay, the 446 is an evap code for the vapor pressure sensor.
Toyota has had this issue for years. The fix I have found is replacing the canister assembly at the back of the car between the 2 rear wheels.
You will need an advanced scan tool to monitor the sensors for the system to test. I attached the wiring diagram and the possible failures but like I said, the most common is the canister.
I attached the part from rock auto for the car as well. It is a plug and play with no programming required.
The vapor pressure sensor and VSV for vapor pressure sensor are used to detect abnormalities in the evaporative emission control system.
The ECM decides whether there is an abnormality in the evaporative emission control system based on the vapor pressure sensor signal.
DTC P0441 and P0446 are recorded by the ECM when evaporative emissions leak from the components within the dotted line in fig. 1 below, or when there is a malfunction in either the VSV for EVAP, the VSV for vapor pressure sensor, or in the vapor pressure sensor itself.
Images (Click to enlarge)
Wednesday, August 5th, 2020 AT 5:01 AM