Cause
Faulty fuel tank pressure sensor
The sensor the evaporative system uses to judge whether the tank holds pressure. It reports the result of every leak test, so a faulty one produces leak codes on a sealed system — and it is far cheaper than the hunt for a leak that is not there.
Typically specialist work. Needs equipment or training most home workshops do not have.
Codes this can cause (19)
Codes where this is a likely explanation first, rather than merely a possible one.
- P0450 Evaporative Emission System Pressure Sensor/Switch A Circuit Likely for this code Low
- P0451 Evaporative Emission System Pressure Sensor/Switch A Circuit Range/Performance Likely for this code Low
- P0452 Evaporative Emission System Pressure Sensor/Switch A Circuit Low Likely for this code Low
- P0453 Evaporative Emission System Pressure Sensor/Switch A Circuit High Likely for this code Low
- P0454 Evaporative Emission System Pressure Sensor/Switch A Circuit Intermittent Likely for this code Low
- P24D6 Evaporative Emission System Pressure Sensor/Switch B Circuit Range/Performance Likely for this code Low
- P2A41 Alternative Fuel Tank B Pressure Sensor Circuit Likely for this code High
- P2A42 Alternative Fuel Tank B Pressure Sensor Range/Performance Likely for this code High
- P2A43 Alternative Fuel Tank B Pressure Sensor Circuit Low Likely for this code High
- P2A44 Alternative Fuel Tank B Pressure Sensor Circuit High Likely for this code High
- P2A45 Alternative Fuel Tank B Pressure Sensor Circuit Intermittent/Erratic Likely for this code High
- P2A46 Alternative Fuel Tank C Pressure Sensor Circuit Likely for this code High
- P2A47 Alternative Fuel Tank C Pressure Sensor Range/Performance Likely for this code High
- P2A48 Alternative Fuel Tank C Pressure Sensor Circuit Low Likely for this code High
- P2A49 Alternative Fuel Tank C Pressure Sensor Circuit High Likely for this code High
- P2A4A Alternative Fuel Tank C Pressure Sensor Circuit Intermittent/Erratic Likely for this code High
- P0440 Evaporative Emission System Malfunction Low
- P0441 Evaporative Emission System Incorrect Purge Flow Low
- P0496 Evaporative Emission System High Purge Flow Low
Information, not instruction
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