P0446
EVAP Vent Control Circuit Malfunction
low
i Description
The EVAP vent control valve circuit has a fault. The vent valve controls airflow through the charcoal canister and is essential for the EVAP leak test.
? Common Causes
- Faulty vent valve
- Blocked vent filter
- Wiring fault
- Spider webs or debris in vent valve
! Symptoms
- Check engine light
- Possible difficulty filling fuel tank (if vent stuck closed)
# Diagnostic Steps
- Test vent valve operation
- Inspect vent filter for blockage
- Check wiring and connector
- Command vent valve with scan tool
⚙ Typical Fix
Replace the vent valve or clear the blockage.
Parts Needed
EVAP vent valve
Estimated Cost
$50-$250
↔ Related Codes
Q Frequently Asked Questions
Yes. If you have trouble filling the fuel tank (pump keeps clicking off), the vent valve may be stuck closed.
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