DTC P0442: Evaporative Emission (EVAP) Control System Leak Detected (Small Leak)

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P0442 - EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM LEAK DETECTED (SMALL LEAK)

Description:	The powertrain control module (PCM) monitors the complete EVAP control system for the presence of a small fuel vapor leak. System failure occurs when a fuel vapor leak from an opening as small as 1.016 mm (0.040 in) is detected by the EVAP running loss monitor test.
Possible Causes:	After market EVAP hardware (such as the fuel filler cap) non-conforming to required specifications Small holes or cuts in the fuel vapor hoses/tubes Canister vent solenoid stays partially open on closed command Damaged, missing or loosely installed fuel filler cap Loose fuel vapor hose/tube connections to the EVAP system components EVAP system component seals leaking (EVAP canister purge valve, fuel tank pressure sensor, canister vent solenoid, fuel vapor control valve tube assembly or fuel vapor vent valve assembly)
Diagnostic Aids:	Check for a missing fuel filler cap or the integrity of the cap. Check for loose or damaged vapor hoses. Visually inspect the EVAP canister inlet port, CV solenoid filter, and canister vent hose assembly for contamination or debris.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	-	-	GO to HX: Evaporative Emission (EVAP) Monitor and System STEP HX52.