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Home >> Ford >> 2009 >> Flex Limited, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1656 (Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid)) >> DTC Diagnosis >> DTC P0442: Evaporative Emission System Leak Detected (Small Leak)

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

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DTC P0442: EVAPORATIVE EMISSION SYSTEM LEAK DETECTED (SMALL LEAK)

Description:  The powertrain control module (PCM) monitors the complete evaporative emission (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: 
  • Aftermarket EVAP hardware that does not conform to the 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
  • Capless fuel tank filler pipe damaged or not sealed correctly (if equipped)
  • Loose fuel vapor hose/tube connections to the EVAP system components
  • EVAP system component seals leaking at or near the EVAP canister purge valve, fuel tank pressure sensor, canister vent (CV) 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. Verify the capless fuel tank filler pipe is sealed correctly (if equipped).
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 PINPOINT TEST HX .