Inspection Procedure 16: Odour, White Smoke, Black Smoke and High-Concentration of CO/HC during Idling


COMMENTS ON TROUBLE SYMPTOM



  • The failure could possibly be caused by the improper air-fuel ratio, deteriorated catalyst, failed ignition system, defective fuel system, faulty compression pressure and so on.

PROBABLE CAUSES



  • Failed air-fuel ratio control system
  • Failed ignition system
  • Failed fuel system
  • Failed intake and exhaust air system
  • Improper compression pressure
  • Deteriorated catalyst
  • Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

Q. Is diagnosis code set?
Inspection chart for diagnosis code (Refer to ).
Go to Step 2.

STEP 2. Check injector for operating sound.

  • Check injector for operating sound (Refer to ).

Q. Is operating sound audible?
Go to Step 3.

    Check the injector system of the defective cylinder.
    (Refer to Code No. P0201: No. 1 Injector System ).
    (Refer to Code No. P0202: No. 2 Injector System ).
    (Refer to Code No. P0203: No. 3 Injector System ).
    (Refer to Code No. P0204: No. 4 Injector System ).

STEP 3. Check ignition timing.

  • Check ignition timing (Refer to GROUP 11E - On-vehicle Service - Ignition Timing Check ).

Q. Is the check result normal?
Go to Step 4.
Check ignition timing deviation (Refer to Inspection Procedure 14 ).

STEP 4. M.U.T.-III data list

  • Refer to Data List Reference Table .

  1. Item 5: No. 1 intake air temperature sensor
  2. Item 6: Engine coolant temperature sensor
  3. Item 10: Air flow sensor
  4. Item BB: Barometric pressure sensor

Q. Are the check results normal?
Go to Step 5.
Perform the diagnosis code classified check procedure for the sensor that has shown an abnormal data value (Refer to Inspection Chart for Diagnosis Code ).

STEP 5. Check air intake from inlet hose and inlet manifold.

Q. Is the check result normal?
Go to Step 6.
Repair.

STEP 6. Check exhaust leak from exhaust manifold.

Q. Is the check result normal?
Go to Step 7.
Repair.

STEP 7. Check throttle body (throttle valve portion) contamination.

Q. Is the check result normal?
Go to Step 8.
Clean throttle body (throttle valve portion) (Refer to ).

STEP 8. M.U.T.-III data list

  • Refer to Data List Reference Table .

  1. Item AC: Oxygen sensor (front)
  2. Item AD: Oxygen sensor (rear)

Q. Are the check results normal?
Go to Step 9.
Perform the diagnosis code classified check procedure for the sensor that has shown an abnormal data value (Refer to Inspection Chart for Diagnosis Code ).

STEP 9. Check purge control solenoid valve itself.

  • Check purge control solenoid valve itself (Refer to GROUP 17 - Emission Control <MPI> - Evaporative Emission Control System - Purge Control Solenoid Valve Check ).

Q. Is the check result normal?
Go to Step 10.
Replace the purge control solenoid valve.

STEP 10. Fuel pressure measurement.

  • Fuel pressure measurement. (Refer to ).

Q. Is the check result normal?
Go to Step 11.
Repair.

STEP 11. Check positive crankcase ventilation valve itself.

  • Check positive crankcase ventilation valve itself (Refer to GROUP 17 - Emission Control <MPI> - Crankcase Emission Control System - Positive Crankcase Ventilation Valve Check ).

Q. Is the check result normal?
Go to Step 12.
Replace the positive crankcase ventilation valve.

STEP 12. Check spark plug.

  • Check spark plug (Refer to GROUP 16 - Ignition System - On-vehicle service - Spark Plug Check and Cleaning ).

Q. Is the check result normal?
Go to Step 13.
Replace the spark plug.

STEP 13. Check compression pressure.

  • Check the compression pressure (Refer to GROUP 11E - On-vehicle Service - Compression Pressure Check ).

Q. Is the check result normal?
Go to Step 14.
Repair.

STEP 14. Check injector for spray condition.

  • Check each injector for spray condition (Refer to ).

Q. Is the check result normal?
Go to Step 15.
Replace the injector.

STEP 15. Replace the catalytic converter.

  • After replacing the catalytic converter, re-check the trouble symptoms.

Q. Does the trouble symptom persist?
Replace the engine-ECU.
Check end.