What P0449 means
An electrical circuit fault at the EVAP vent valve — commonly corrosion, since the valve lives under the car.
Common causes
- Corroded connector at the vent valve
- Failed solenoid
- Damaged harness
How it is usually fixed
- 1Clean and reseal the connector
- 2Replace the vent valve if the solenoid is open
- 3Repair the harness
Other common codes
- P0011 — Camshaft Position A – Timing Over-Advanced (Bank 1)
- P0030 — HO2S Heater Control Circuit (Bank 1, Sensor 1)
- P0101 — Mass Air Flow Circuit Range/Performance
- P0113 — Intake Air Temperature Sensor Circuit High
- P0118 — Engine Coolant Temperature Sensor Circuit High
- P0131 — O2 Sensor Circuit Low Voltage (Bank 1, Sensor 1)
Code information is general guidance, not a diagnosis for a specific vehicle. Confirm with live data and manufacturer test procedures before replacing parts.