All codes › P0446
P0446: Evaporative Emission System Vent Control Circuit
What it means
The EVAP vent valve control circuit has a fault, so the system can't seal for its leak test.
Severity: Low EVAP leak test can't run.
Common causes
- Stuck or failed vent valve
- Spider webs/debris in vent filter
- Wiring fault
- Clogged canister
Most common causes first. Exact causes vary by make, model and engine.
Can I fix it myself?
Sometimes DIY. Vent valve is near the canister by the fuel tank; check for debris.
Repair cost
SEEDED ESTIMATE Roughly $80–$430
Most likely repair: evap purge/vent valve. Diagnosis fees, taxes and other causes are not included.
| Line | Low | High | Basis |
|---|---|---|---|
| EVAP purge/vent valve | $34 | $190 | Typical listed retail range, source |
| Labor 0.5–1.5 hr | $50 | $240 | $100–$160/hr, shop survey |
⚠️ This is an editorial placeholder range for this type of repair. It is not based on real invoices or licensed pricing data yet. Real ranges will appear here once enough reader invoices for P0446 are verified.
Verified reader invoices for P0446: 0. Share your repair bill to help build real costs.
Tools that can read P0446
- ScanFixAI: Pro $29.99/mo or $249.99/yr
- OBDAI: Annual PRO bundle $299
- BlueDriver Pro Next-Gen: $119.95 list ($99.95 sale seen)
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