OBD II Trouble Code P0442 indicates an Evaporative Emission Control System Leak Detected (small leak). It means your vehicle's engine control unit has detected a very small leak. The leak can be from a hole as small as 0.04" in diameter.
The EVAP system is designed to prevent the release of gasoline vapors into the atmosphere. Fuel vapors are routed by hoses to a charcoal canister. The charcoal canister is responsible for storing gasoline vapors from the vehicle's fuel tank until the engine is ready to burn them through the combustion process.
A code P0442 is usually caused by:
- A loose or improperly affixed gas cap.
- A non-EOM gas cap (one that is not fitted for your vehicle).
- A small leak/hole in a fuel vapor hose.
The first thing we recommend doing when dealing with trouble code P0442, to remove and reinstall the gas cap, clear the trouble codes using an OBD scanner and driving for a few day to see if the codes come back. If the code returns spending a few dollars on a replacement gas cap (preferably one from the dealer) may be worth a shot. If the code still returns you will need to have the EVAP system inspected for leaks.
