P0446: Evaporative Emission Control System Vent Control Circuit
P0446 typically points to the vent valve on the charcoal canister. It's a common code on Toyota/Lexus vehicles.
Severity: low · System: Powertrain · Safe to drive: usually, short-term. Not urgent. Emissions-related only.
Symptoms
- Check engine light only
Common causes
- Failed EVAP vent valve
- Charcoal canister clogged
- Wiring/connector issue
Fair repair prices
| EVAP vent valve | $100–$250 |
|---|---|
| Charcoal canister | $250–$600 |
Ranges are US market averages (parts and labor). If your shop's quote is above the high end, ask for a line-item breakdown or run it through the invoice checker.
Other codes
- P0300 — Random / Multiple Cylinder Misfire Detected
- P0301 — Cylinder 1 Misfire Detected
- P0420 — Catalyst System Efficiency Below Threshold (Bank 1)
- P0430 — Catalyst System Efficiency Below Threshold (Bank 2)
- P0171 — System Too Lean (Bank 1)
- P0174 — System Too Lean (Bank 2)
- P0442 — Evaporative Emission Control System Leak (Small)
- P0455 — Evaporative Emission Control System Leak (Large)