Possible Causes
WARNING: This page is about a different car, the 2003 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.
DTCs P0451, P0452 or P0453 is set by the ECM when the VPS malfunctions. Possible causes are:
- Vapor pressure sensor circuit is open or shorted.
- Defective vapor pressure sensor.
- Defective ECM.