P0446 Ford Bronco
EVAP Vent Control Circuit Malfunction · Powertrain Code · Low · Repair: Moderate
What is P0446?
The EVAP vent control circuit has an electrical issue preventing proper vent valve operation.
When the Ford Bronco triggers code P0446 (evap vent control circuit malfunction), it typically points to an issue in the powertrain system. Below you'll find the most common causes, symptoms, and repair options specific to the Ford Bronco.
This repair is rated moderate, meaning some experience and specialty tools required.
Diagnostic data on this page is compiled from publicly available repair resources and technical service bulletins. Always have a qualified mechanic confirm the diagnosis before authorizing repairs on your Ford Bronco.
Common Causes on Ford Bronco
- Failed EVAP vent valve (canister close valve) — stuck open or closed
- Blocked EVAP vent filter or hose near the charcoal canister
- Wiring issue to the EVAP vent valve
- Debris or spider webs blocking the vent line (common on vehicles parked outdoors)
Symptoms
- Check engine light
- Difficulty filling the gas tank (pump keeps clicking off)
- Fuel vapor smell near rear of vehicle
- No driveability symptoms typically
Notes for Ford Bronco
If the gas pump keeps clicking off when filling up, P0446 with a stuck-closed vent valve is the most likely cause on Ford trucks.