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Home >> Infiniti >> 2014 >> QX50 Base, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTCS P0137 To P0456 >> DTC P0456: EVAP Control System >> Component Inspection
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Component Inspection

  1. CHECK FUEL TANK VACUUM RELIEF VALVE 
    1. Turn ignition switch OFF.
    2. Remove fuel filler cap. Refer to "EXPLODED VIEW ".
    3. Wipe clean valve housing.
      Fig 1: Identifying Pressure And Vacuum Valve, Spring Gasket And Plate
      G09171832Courtesy of NISSAN NORTH AMERICA, INC.
    4. Check valve opening pressure and vacuum.

      Pressure: 15.3 - 20.0 kPa (0.156 - 0.204 kg/cm 2  , 2.22 - 2.90 psi) 

      Vacuum: -6.0 to -3.3 kPa (-0.061 to -0.034 kg/cm 2  , -0.87 to -0.48 psi) 

      Is the inspection result normal? 

      YES: INSPECTION END

      NO: GO TO 2.

      Fig 2: Checking Valve Opening Pressure And Vacuum Using Suitable Tool
      G09171833Courtesy of NISSAN NORTH AMERICA, INC.
  2. REPLACE FUEL FILLER CAP 

    Replace fuel filler cap. Refer to "EXPLODED VIEW ".

    CAUTION: Use only a genuine fuel filler cap as a replacement. If an incorrect fuel filler cap is used, the MIL may illuminate.

    : INSPECTION END