P0442 Evap Emission Control Small Leak Detected
Gas cap not on tight or bad, Purge valve bad or unhooked, lines bad or off. canister bad ect.
A small leak/hole in a fuel vapor hose/tube. Other small leak in EVAP system. Faulty vent o-ring seal. Defective vent valve Defective purge valve Defective leak detection pump. 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 (we recommend an OEM not aftermarket part), or Inspect the EVAP system for cuts/holes in tubes/hoses. More advanced troubleshooting steps include: Using an advanced scan tool, perform an EVAP leak test Verify operation of the EVAP purge solenoid / valve Perform a smoke test to see where the leak is.
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.
The vehicle's PCM (powertrain control module) tests the evaporative emissions (EVAP) system for large and small leaks among other conditions. In the case of this DTC, it indicates a fuel vapor leak in the EVAP control system. It means a very small leak has been detected. In fact, the leak can be from a hole as small as 0.04" in diameter. The (EVAP) emission control system prevents the escape of fuel vapors from a vehicle's fuel system.
small as .020" in dia.
You'll need a smoke test done to find out where the leak is. The leak can be so small it can't be seen with the naked eye. HTH. -Jim
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