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What causes the P0446 code?
- Faulty, missing, or broken gas cap
- Faulty EVAP system hose
- A Leaking fuel tank
- Broken or faulty charcoal canister
What are the symptoms of the P0446 code?
- The Check Engine Light being present.
- A fuel odor may be noticed and the fuel economy may suffer slightly.
Also found this:
P0446 FORD code possible causes
Missing Fuel cap
Incorrect fuel filler cap used
Fuel filler cap remains open or fails to close
Foreign matter caught in fuel filler cap
Vent control valve harness is open or shorted
Vent control valve circuit poor electrical connection
Faulty vent control valve
The Evaporative System (EVAP) canister vent control valve is located on the EVAP canister and is used to seal the canister vent.