Inspection Procedure 6: Starting Impossible (Initial Combustion But No Complete Combustion), Improper Starting (Long Time to Start)


COMMENTS ON TROUBLE SYMPTOM



  • Failure is possibly caused by poor ignition, incorrect air-fuel ratio at cranking, improper fuel pressure and so on.

PROBABLE CAUSES



  • Failed battery
  • Failed ignition system
  • Failed fuel system
  • Failed air-fuel ratio control system
  • Failed intake air system
  • Failed exhaust gas cleaning system
  • Contamination around the throttle valve
  • Timing chain in out of place
  • Improper compression pressure
  • Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check battery voltage.

  • Measure battery voltage at cranking.
OK: 8 V or more

Q. Is the check result normal?
Go to Step 2 .
Battery check (Refer to GROUP 54A - Battery - On-vehicle Service - Battery Test ).

STEP 2. M.U.T.-III diagnosis code

Q. Is diagnosis code set?
Inspection chart for diagnosis code (Refer to ).
Go to Step 3 .

STEP 3. M.U.T.-III data list

  • Refer to Data List Reference Table .

  1. Item 5: Intake air temperature sensor
  2. Item 6: Engine coolant temperature sensor
  3. Item 8: Manifold absolute pressure sensor
  4. Item 10: Air flow sensor

Q. Are the check results normal?
Go to Step 4 .
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 4. Check throttle body (throttle valve portion) contamination.

Q. Is the check result normal?
Go to Step 5 .
Clean throttle body (throttle valve portion) (Refer to Throttle Body (Throttle Valve Area) Cleaning ).

STEP 5. M.U.T.-III actuator test

  • Item 9: Fuel pump
OK: Operating sound of fuel pump can be heard.

Q. Is the check result normal?
Go to Step 6 .
Check fuel pump system (Refer to Inspection Procedure 20 ).

STEP 6. Check air intake from intake hose and inlet manifold.

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

STEP 7. Check injector for operating sound.

  • Check injector for operating sound at engine cranking (Refer to ).

Q. Is operating sound audible?
Go to Step 8 .

    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 8. Check timing mark on the timing chain.

Q. Is the check result normal?
Go to Step 9 .
Align the timing marks.

STEP 9. Visual check of ignition spark.

  • Remove the spark plug and install it to the ignition coil.
  • Connect the ignition coil connector.
  • Remove all injector connector.
  • At the engine start, check each spark plug produces a spark.

Q. Is the check result normal?
Go to Step 11 .
Go to Step 10 .

STEP 10. 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?
Check ignition circuit system (Refer to Inspection Procedure 22 ).
Replace the spark plug.

STEP 11. Check injector for spray condition.

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

Q. Is the check result normal?
Go to Step 12 .
Replace the injector.

STEP 12. Fuel pressure measurement.

  • Fuel pressure measurement (Refer to Fuel Pressure Test ).

Q. Is the check result normal?
Go to Step 13 .
Repair.

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 exhaust gas recirculation valve itself.

  • Check Exhaust gas recirculation valve itself (Refer to GROUP 17 - Emission Control <MPI> - Exhaust Gas Recirculation (EGR) Valve - Exhaust Gas Recirculation Valve (Stepper Motor) Check ).

Q. Is the check result normal?
Go to Step 15 .
Replace the exhaust gas recirculation valve.

STEP 15. Replace the engine-ECU.

  • After the engine-ECU has been replaced, check for the trouble symptom again.

Q. Does the trouble symptom persist?
Check for foreign matters (water, kerosene, etc.) in fuel and replace if necessary.
Check end.