OBD codes / P0456
P0456
MinorEvaporative Emission System Leak Detected (Very Small Leak)
Usually safe to drive; fix at your convenience.
Likely causes
- slightly loose gas cap
- tiny hose crack
Common fixes
- replace gas cap
- smoke-test EVAP
Seeing P0456 on your car? Get a diagnosis specific to your exact year, make and model.
Diagnose P0456 for my vehicleGeneric OBD-II reference. Manufacturer-specific behavior varies — confirm with a scan tool and, for safety-related codes, a professional inspection.