DTC P0450: EVAP Pressure Sensor Circuit, Or DTC P0451: EVAP Pressure Sensor Range/Performance: Notes
WARNING: This page is about a different car, the 2000 Toyota RAV4. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
If ECM replacement is instructed in following testing, always ensure ECM connectors and ground circuit are okay. If either are suspect, repair and repeat testing to confirm ECM malfunction.