All codes › P0440
P0440: Evaporative Emission System
What it means
There's a general fault in the evaporative emission (fuel vapor) system.
Severity: Low No drivability effect.
Common causes
- Loose or bad gas cap
- Faulty purge or vent valve
- Cracked EVAP line
- Leaking canister
Most common causes first. Exact causes vary by make, model and engine.
Can I fix it myself?
Often DIY. Start with the gas cap; then inspect EVAP lines.
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 P0440 are verified.
Verified reader invoices for P0440: 0. Share your repair bill to help build real costs.
Tools that can read P0440
- 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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