P0446 means evap vent control circuit. The vent valve circuit has an electrical fault. The vent valve seals the EVAP system during leak tests — if the circuit
You can keep driving — get it checked when convenient.
The vent valve circuit has an electrical fault. The vent valve seals the EVAP system during leak tests — if the circuit fails, the system can't test itself.
Most common.
Open/short in the circuit.
Especially in rust-belt cars.
Check first.
Rare.
Typically $100–$400
Vent valve replacement typically $150–$400. Estimates vary by vehicle. Costs are estimates and vary by vehicle, location, and shop.
Safe to drive. Emissions-only issue; fix at your convenience.
Typically $100–$400. Vent valve replacement typically $150–$400. Estimates vary by vehicle.
You can keep driving — get it checked when convenient.
The most common cause is failed vent valve solenoid. Most common.