Inspection Procedure 10: A Large Amount of Fuel Consumption




PROBABLE CAUSES




DIAGNOSIS PROCEDURE


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


Q. Is the diagnosis code set?

Inspection chart for diagnosis code (Refer to ).
Go to Step 2.

STEP 2. Check whether other trouble symptoms are occurring.


Q. Are other trouble symptoms occurring?

Inspection chart for trouble symptoms (Refer to ).
Go to Step 3.

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



  • Refer to Data List Reference Table .

    1. Item 5: Barometric pressure sensor
    2. Item 6: Manifold absolute pressure sensor
    3. Item 7: Engine coolant temperature sensor
    4. Item 8: EGR gas temperature sensor
    5. Item 9: Accelerator pedal position sensor (main)
    6. Item 10: Accelerator pedal position sensor (sub)
    7. Item 16: EGR valve position sensor
    8. Item 21: Fuel temperature sensor
    9. Item 43: Intake air temperature sensor
    10. Item 45: Throttle position 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 injector identification code.



  • Check injector identification code (Refer to GROUP 00 - Precautions before Service - Injector Identification Code Registration Procedure <4N1> ).

Q. Is the check result normal?

Go to Step 5.
Register the injector ID.

STEP 5. Small injection quantity learning.



  • Carry out the small injection quantity learning procedure (Refer to GROUP 00 - Precautions before Service - Small Injection Quantity Learning Procedure <4N1> ).

Q. Does the trouble symptom persist?

Go to Step 6.
Check end.

STEP 6. Check the turbocharging pressure.



  • Check the turbocharging pressure (Refer to GROUP 15 - On-vehicle Service - Turbocharger Supercharging Pressure Check ).

Q. Is the check result normal?

Go to Step 7.
Repair.

STEP 7. Check thermostat.



  • Check thermostat (Refer to GROUP 14 - Thermostat and Thermostat Case <4N1> - Thermostat Inspection ).

Q. Is the check result normal?

Go to Step 8.
Replace the thermostat.

STEP 8. M.U.T.-III actuator test.



  • Refer to Actuator Test Reference Table .

    1. Item 19: Suction control valve

Q. Is the check result normal?

Go to Step 9.
Check suction control valve system (Refer to Code No. P0003 , Refer to Code No. P0004 ).

STEP 9. M.U.T.-III data list.



  • Refer to Data List Reference Table .

    1. Item 63: Rail pressure sensor
    2. Item 64: Rail pressure target

Q. Are the check results normal?

Go to Step 12.
Go to Step 10.

STEP 10. Replace the fuel pressure sensor.



  • After replacing the common-rail assembly, re-check the trouble symptoms.

Q. Does the trouble symptom persist?

Go to Step 11.
Check end.

STEP 11. Check the trouble symptoms.


Q. Does the trouble symptom persist?

Replace the supply pump assembly.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

STEP 12. Check injector itself.



  • Injector connector check.
  • Check injector itself (Refer to ).

Q. Is the check result normal?

Go to Step 13.
Repair or replace the connector, or replace the injector at the failed cylinder.

STEP 13. Check compression pressure.



  • Check 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 the trouble symptoms.


Q. Does the trouble symptom persist?

Replace the engine-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).