P0446: Evaporative Emission Control System Vent Control Circuit Malfunction
What this check-engine code means in plain English, what usually causes it, and what a fix typically costs.
What P0446 means
The EVAP system prevents fuel vapors from escaping into the atmosphere by storing them in a charcoal canister and purging them into the engine. P0446 means the powertrain control module has detected a problem with the vent valve circuit that allows fresh air into the system, either due to an electrical fault or a stuck valve.
What causes P0446?
Is P0446 safe to drive?
This code does not affect drivability or safety, so you can continue driving normally. However, the vehicle will likely fail an emissions inspection, and unresolved EVAP issues can sometimes lead to fuel odors or slightly reduced fuel economy over time.
P0446 repair cost
Industry-average estimates. Cost depends on whether it's a simple vent valve replacement or requires wiring repair and diagnostic labor.
Which one is it for your car?
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