P0446low severityPowertrain
EVAP Vent Control Circuit
on 2008-2015 Audi R8 4.2L V8 · AWD
What this code 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
Repair notes
Replace vent valve or clean vent. Check for debris in vent hose.
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