P0440
EVAP System
Powertrain · Generic (all makes)System: Emissions
Safe to drive short term. Book a repair.
Likely causes
- Loose or bad gas cap
- Cracked EVAP hose
- Faulty purge or vent valve
- Leaking charcoal canister
What to check first
Start with the gas cap. If the code returns, a smoke test finds the leak in the EVAP system.
Typical repair cost
$50 – $500
Independent-shop parts and labor for the usual fix. Your price depends on the actual cause and the vehicle.
Next step
General information, not a diagnosis of your vehicle. Repair costs are typical shop ranges, not quotes.