Check Engine Code
P0446
Evaporative Emission Control System Vent Control Circuit Malfunction
Severity: low
DIY difficulty: 2/5
Typical cost: $40–$300
What P0446 means
The vent valve controls fresh-air flow into the EVAP system during purge. P0446 typically points at a failed vent solenoid or a clogged canister (spiders love to nest in the vent line).
Symptoms
- Check engine light
- Possible slow refueling / fuel gushing back
Likely causes (most common first)
- Failed vent valve solenoid
- Spiders/debris clogging the vent filter or line (more common than you'd think)
- Damaged wiring to the vent valve
- Saturated charcoal canister
Can I keep driving?
Low — mostly emissions/economy
Typical repair cost
DIY fixes can start near $40 (parts only). Shop repairs for P0446 typically run up to $300 depending on the underlying cause and vehicle. Start with the most common cause — Failed vent valve solenoid — before throwing parts at it.
Related codes
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