OBD-II code · Powertrain (generic)
P0446 Evaporative Emission Vent Control Circuit Malfunction
A fault in the EVAP vent valve circuit. The vent valve seals the canister against atmosphere during the leak test; without it, the test cannot pull a vacuum and may set false leak codes alongside.
Is it safe to drive with P0446?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyVent valve seized or contaminated by water/dirt
- PossibleWiring or connector fault
Symptoms
- Check engine light on
- Possible smell of fuel near tank or engine bay
- Failed emissions inspection
- Loose-cap warning may appear
Repair at a glance
- Difficulty
- Easy
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.3–1.5 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Evap Vent Valve, Evap Vent Valve Wiring
Related codes
- P0443Evaporative Emission System Purge Control Valve Circuit
- P0444Evaporative Emission Purge Control Valve Circuit Open
- P0445Evaporative Emission System Purge Control Valve Circuit Shorted
- P0447Evaporative Emission System Vent Control Circuit Open
- P0448EVAP System Vent Control Circuit Shorted
- P0449Evaporative Emission System Vent Valve/Solenoid Circuit Malfunction
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.