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Home >> Infiniti >> 2004 >> M45 >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> Engine Control System >> DTC P1456: EVAP Control System >> Overall Function Check >> With GST
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With GST

Use this procedure to check the overall function of the EVAP very small leak function. During this check, a 1st trip DTC might not be confirmed.

CAUTION:
  • Never use compressed air, doing so may damage the EVAP system.
  • Do not start engine.
  • Do not exceeded 4.12 kPa (0.042 kg/cm2 , 0.6 psi).
  1. Attach the EVAP service port adapter securely to the EVAP service port.
    Fig 1: Identifying EVAP Service Port
    G00796483Courtesy of NISSAN MOTOR CO., U.S.A.
  2. Set the pressure pump and a hose.
  3. Also set a vacuum gauge via 3-way connector and a hose.
  4. Turn ignition switch ON.
  5. Connect GST and select MODE 8.
  6. Using MODE 8 control the EVAP canister vent control valve (close) and vacuum cut valve bypass valve (open).
    Fig 2: Identifying EVAP Service Port Adapter & Pump
    G00796484Courtesy of NISSAN MOTOR CO., U.S.A.
  7. Apply pressure and make sure the following conditions are satisfied.

    Pressure to be applied: 2.7 kPa (20 mmHg, 0.79 inHg) 

    Time to be waited after the pressure drawn in to the EVAP system and the pressure to be dropped: 60 seconds and the pressure should not be dropped more than 0.4 kPa (3 mmHg, 0.12 inHg). 

    If NG, go to DIAGNOSTIC PROCEDURE .

    If OK, go to next step.

  8. Disconnect GST.
  9. Start engine and warm it up to normal operating temperature.
  10. Turn ignition switch OFF and wait at least 10 seconds.
  11. Restart engine and let it idle for 90 seconds.
  12. Keep engine speed at 2,000 RPM for 30 seconds.
  13. Turn ignition switch OFF.
    NOTE: For more information, refer to GST Instruction Manual.