OBD codes / P0440
P0440
MinorEvaporative Emission System Malfunction
Usually safe to drive; fix at your convenience.
Likely causes
- loose gas cap
- EVAP hose/valve fault
Common fixes
- replace gas cap
- smoke-test EVAP
Seeing P0440 on your car? Get a diagnosis specific to your exact year, make and model.
Diagnose P0440 for my vehicleGeneric OBD-II reference. Manufacturer-specific behavior varies — confirm with a scan tool and, for safety-related codes, a professional inspection.