Possible causes

– Faulty Evaporative Emission System (EVAP) Vapor Pressure Sensor
– Evaporative Emission System (EVAP) Vapor Pressure Sensor harness is open or shorted
– Evaporative Emission System (EVAP) Vapor pressure sensor circuit poor electrical connection
– Faulty Engine Control Module (ECM)

When is the code detected?

10 seconds or less after engine starting condition vapor pressure sensor fixed value continues for fixed value or more.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P0450 TOYOTA Description

The Evaporative Emission System (EVAP) vapor pressure sensor, VSV for canister closed valve (CCV) and VSV for pressure switching valve are used to detect abnormalities in the evaporative emission control system. The Engine Control Module (ECM) decides whether there is an abnormality in the evaporative emission control system based on the vapor pressure sensor signal.

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