P0446
PowertrainEvap Systemlow severityEVAP Vent Control Circuit
What P0446 Means
Malfunction in the EVAP vent control circuit. The vent valve controls airflow to the charcoal canister.
Symptoms
- Check Engine Light
- Fuel tank pressure issues
- Difficulty refueling
Common Causes
- Faulty vent valve
- Blocked vent filter
- Wiring issue
- Spider webs/debris in vent hose
Diagnostic Steps
- Test vent valve operation
- Inspect vent filter
- Check wiring
- Inspect vent hose for blockage
Where to start: Replace vent valve or clean vent. Check for debris in vent hose.
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