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Home >> Ford >> 2021 >> Bronco Base, 2D Utility, 2.7L Eng VIN P, Part Time T/Case Control >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Memory Modules >> Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid) >> Diagnostic Trouble Code (DTC) Charts And Descriptions >> P0457 - EVAP System Leak Detected (Fuel Cap Loose/Off)
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P0457 - EVAP System Leak Detected (Fuel Cap Loose/Off)

DTC DESCRIPTION P0457 - EVAP SYSTEM LEAK DETECTED (FUEL CAP LOOSE/OFF)

Description:  The PCM continuously monitors the fuel level and retains the last updated value prior to the ignition switch being placed in the OFF position. After the ignition switch is placed in the ON position a new fuel level is taken and compared to the level recorded at ignition OFF. If the fuel level has increased, a flag is set in the PCM indicating the vehicle was refueled. This DTC sets when the evaporative emission (EVAP) monitor detects a gross leak while the refueling flag is set and a loose fuel filler cap (if equipped) or an incorrectly sealed capless fuel tank filler pipe (if equipped) is suspected. On most vehicles, when the DTC sets, a message on the instrument panel cluster (IPC) displays to instruct the driver to check the fuel cap or capless fuel tank filler pipe (if equipped).
Possible Causes: 
  • Damaged, missing, or loosely installed fuel filler cap (if equipped)
  • Capless fuel tank filler pipe damaged or not sealed correctly (if equipped)
Diagnostic Aids:  Check for a missing fuel filler cap or the integrity of the cap (if equipped). Verify the capless fuel tank filler pipe is sealed correctly (if equipped). Install and remove the supplemental fueling adapter five times in the capless fuel tank filler pipe to clear debris on the seal. Refer to the Owner Literature for the location of the supplemental fueling adapter in the vehicle. If OK, clear the continuous memory DTCs and test the system for correct operation.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to Pinpoint Test HX.