RE: Check engine light: code 455
P0455 =Evaporative Emission Control System Leak Detected (no purge flow or large leak)
This indicates a fuel vapor leak or lack of purge flow in the EVAP control system. It means a large leak has been detected. The (EVAP) emission control system prevents the escape of fuel vapors from a vehicle's fuel system. Fuel vapors are routed by hoses to a charcoal canister for storage. Later, when the engine is running a purge control valve opens allowing intake vacuum to siphon the fuel vapors into the engine.
AP0455 most likely means one or more of the following has happened:
- A loosegas cap
- A non-conforming gas cap (i.e. not factory/original brand)
- Other leak or damaged piece in EVAP system
The most common repair is to:
- Remove and reinstall the gas cap, clear the codes, and drive for a day and see if the codes come back.
- Otherwise, replace the gas cap, and/or
- Inspect the EVAP system for cuts/holes in tubes/hoses (you may hear a vacuum noise or smell fuel), repair if necessary