ECD SYSTEM Engine Knocking or Rattling

DESCRIPTION

Malfunction Condition Main Trouble Area Related Trouble Area

  • Knocking and abnormal sound due to extremely rich combustion

  • Abnormal sound due to friction between parts

(a) Injector assembly malfunctions


  • Injector sliding malfunction

  • Injector stuck closed

  • Injector stuck open

  • Deposits in injector

  • Injector circuit malfunction

(b) Abnormal common rail pressure


  • Suction control valve (fuel supply pump assembly)

  • Fuel pulsation sound

  • Air in fuel

(c) Friction between parts

(d) Compression pressure

  • Injector compensation codes

  • Fuel leakage

  • Intake air system leakage

  • Intake air system blockage

  • Throttle valve system

  • Fuel pressure sensor (common rail assembly)

  • Manifold absolute pressure sensor

  • Mass air flow meter

  • Atmospheric pressure sensor (built into ECM)

  • Vehicle modifications

  • Low quality fuel

  • Lack of fuel

  • ECM

Tech Tips


  • Specified values in the following troubleshooting flowchart are for reference only. Variations in the Data List values may occur depending on the measuring conditions or the vehicle's age. Do not judge the vehicle to be normal even when the Data List values indicate a standard level. There are possibly some concealed factors of the malfunction.

  • Check that the vehicle has not been modified in any way prior to the vehicle inspection.

CAUTION / NOTICE / HINT

Tech Tips


  • This troubleshooting procedure checks for knocking and rattling.

  • Knocking is most likely to occur while the engine is idling.

Note


  • After replacing the ECM, the new ECM needs registration (See page ) and initialization Click here.

  • After replacing the fuel supply pump, the ECM needs initialization Click here.

  • After replacing an injector assembly, the ECM needs registration Click here.

PROCEDURE


  1. CHECK SOUND AREA


    1. Find the source of the abnormal sound using a mechanic's stethoscope.

      Result
      Result Proceed to
      Combustion noise from engine A
      Noise from specific part B

    B

    REPAIR OR REPLACE MALFUNCTIONING PARTS

    A

  2. READ OUTPUT DTCS (RELATING TO ENGINE)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine / Trouble Codes.


      Powertrain > Engine > Trouble Codes

    4. Read the DTCs.

      Result

      Result
      Result Proceed to
      No output A
      Engine related DTCs B

    B

    GO TO DTC CHART Click here

    A

  3. CHECK INJECTOR COMPENSATION CODE

    Note

    Injector compensation codes are unique, 30-digit, alphanumeric values printed on the head portion of each injector assembly. If an incorrect injector compensation code is input into the ECM, the engine may rattle or engine idling may become rough. In addition, engine failure may occur and the life of the engine may be shortened.


    1. Check the injector compensation code.

      Click here

      OK
      Compensation codes of the installed injector assemblies are the same as the compensation codes registered in the ECM.
      Result
      Proceed to
      OK
      NG

    NG

    GO TO STEP 10 Click here

    OK

  4. TAKE SNAPSHOT DURING IDLING AND 4000 RPM (AFTER ENGINE WARMED UP)


    1. Connect the GTS to the DLC3.

    2. Start the engine and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine / Data List / All Data.

    4. Take a snapshot of the following Data List items.

      Tech Tips


      • A snapshot can be used to compare vehicle data from the time of the malfunction to normal data and is very useful for troubleshooting. The data in the list below is that of a normal vehicle, but as the data varies between individual vehicles, this data should only be used for reference.

      • Check the Data List at idling and at 4000 rpm with no load after the engine is warmed up.

      Result
      Proceed to
      NEXT

    NEXT

  5. CHECK SNAPSHOT (INJECTION FEEDBACK VAL #1 TO #4 AND INJECTION VOLUME)


    1. Check Injection Feedback Val #1 to #4 and Injection Volume in the snapshot taken when the engine was idling and at 4000 rpm with no load.

      Result
      Result Proceed to

      Injection Feedback Val for at least one cylinder is more than +3 mm3/st

      		 A

      Injection Volume is 10 mm3/st or less at 4000 rpm

      		 B
      Except above C

      Tech Tips


      • When there is a problem with the operation of an injector assembly due to foreign matter in the inside of the injector assembly, etc., the fuel injection volume decreases. As a result, the ECM gives instructions to increase the fuel injection volume, which causes Injection Feedback Val to increase.

      • The ECM controls the system so that the sum of Injection Feedback Val for all of the cylinders is approximately 0 mm3/st. Even if the value of Injection Feedback Val for a cylinder is less than -3.0 mm3/st (-3.0 mm3/st is the lowest normal value), as long as the value of Injection Feedback Val for each of the other cylinders is 3.0 mm3/st or less, the injector assemblies are not malfunctioning.


    B

    REPLACE FUEL INJECTORS OF ALL CYLINDERS Click here

    C

    CHECK SNAPSHOT (COMMON RAIL PRESSURE AND TARGET COMMON RAIL PRESSURE) Click here

    A

  6. PERFORM ACTIVE TEST USING GTS (CHECK THE CYLINDER COMPRESSION)

    Tech Tips

    Use this Active Test to help determine whether a cylinder has compression loss or not.


    1. Connect the GTS to the DLC3.

    2. Start the engine and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine / Active Test / Check the Cylinder Compression / Data List / Compression / Engine Speed of Cyl #1 to #4.


      Powertrain > Engine > Active Test
      Active Test Display
      Check the Cylinder Compression
      Data List Display
      Engine Speed of Cyl #1
      Engine Speed of Cyl #2
      Engine Speed of Cyl #3
      Engine Speed of Cyl #4

    4. Check the engine speed during the Active Test.

      Result
      Result Proceed to
      Except below A
      The values of Engine Speed Cyl #1 to #4 are within 10 rpm of each other. B

      Tech Tips

      When cranking, if the speed of a cylinder is approximately 100 rpm more than the other cylinders, there is probably a complete loss of compression in that cylinder.


    B

    GO TO STEP 8 Click here

    A

  7. CHECK CYLINDER COMPRESSION PRESSURE


    1. Check the cylinder compression pressure.

      Click here

      Tech Tips

      When compression is low, there may be cracks in the piston or the injector may be installed improperly.

      Result
      Proceed to
      OK
      NG

    NG

    CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION

    OK

  8. REPLACE INJECTOR ASSEMBLY OF MALFUNCTIONING CYLINDER


    1. Replace the injector assembly of the malfunctioning cylinder.

      Click here

      Note


      • When replacing the injector assembly for a cylinder, always be sure to use a new injection pipe.

      • Follow the procedure in the repair manual and temporarily install the injection pipes and nozzle leakage pipe, and then correctly position the injector assemblies. After that, tighten parts according to the torque specifications.

      • If the installation procedure is not performed correctly, injector assemblies may become out of position, which may cause the injector assemblies to deteriorate, resulting in malfunctions.

      • If an injector assembly deteriorates and malfunctions, other problems such as knocking, rough idle, etc. may occur.

      • If an injector assembly becomes out of position, it is possible that the seal between the injector assembly and injection pipe may become incomplete, resulting in a fuel leak.

      Result
      Proceed to
      NEXT

    NEXT

  9. CLEAN OR REPLACE FUEL FILTER ASSEMBLY


    1. Clean the interior of the fuel filter case.

    2. If the fuel filter is obviously dirty or clogged, replace the fuel filter assembly.

      Result
      Proceed to
      NEXT

    NEXT

  10. REGISTER INJECTOR COMPENSATION CODE AND PERFORM PILOT QUANTITY LEARNING


    1. RegisRegister the injector compensation codes.

      Click here

    2. Perform the fuel injector pilot quantity learning.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  11. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  12. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Check whether the knocking has been successfully repaired.

      Result
      Proceed to
      NEXT

    NEXT

    END

  13. REPLACE FUEL INJECTORS OF ALL CYLINDERS


    1. Replace the fuel injectors.

      Click here

      Note


      • When replacing the injector assembly for a cylinder, always be sure to use a new injection pipe.

      • Follow the procedure in the repair manual and temporarily install the injection pipes and nozzle leakage pipe, and then correctly position the injector assemblies. After that, tighten parts according to the torque specifications.

      • If the installation procedure is not performed correctly, injector assemblies may become out of position, which may cause the injector assemblies to deteriorate, resulting in malfunctions.

      • If an injector assembly deteriorates and malfunctions, other problems such as knocking, rough idle, etc. may occur.

      • If an injector assembly becomes out of position, it is possible that the seal between the injector assembly and injection pipe may become incomplete, resulting in a fuel leak.

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 9 Click here

  14. CHECK SNAPSHOT (COMMON RAIL PRESSURE AND TARGET COMMON RAIL PRESSURE)


    1. Check Common Rail Pressure and Target Common Rail Pressure in the snapshot taken when the engine was warmed up and idling.

      OK
      Common Rail Pressure is within 5000 kPa of Target Common Rail Pressure.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FUEL SUPPLY PUMP ASSEMBLY (SUCTION CONTROL VALVE) Click here

    OK

  15. PERFORM PILOT QUANTITY LEARNING (DETAIL)


    1. Perform the pilot quantity learning (detail).

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  16. CHECK ENGINE KNOCKING OR RATTLING


    1. Check engine knocking or rattling.

      Result
      Result Proceed to
      Sound disappears A
      Except above (Sound continues occurring) B

    B

    END

    A

  17. CHECK THE TEMPERATURE WHEN KNOCKING OCCURS


    1. Check the temperature when knocking trouble occurs.

      Result
      Result Proceed to
      Knocking occurs only in cold engine A
      Knocking occurs both in cold and warmed up engine B

    B

    READ VALUE USING GTS (MAP AND ATMOSPHERE PRESSURE) Click here

    A

  18. INSPECT GLOW PLUG (RESISTANCE)


    1. Inspect the glow plug.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE GLOW PLUG Click here

    OK

  19. TAKE SNAPSHOT DURING IDLING (WHEN ENGINE COLD)


    1. Make sure that the engine is cold so that the snapshot can be taken under the correct conditions.

    2. Connect the GTS to the DLC3.

    3. Start the engine and turn the GTS on.

    4. Enter the following menus: Powertrain / Engine / Data List / All Data.

    5. Take a snapshot of the following Data List items.

      Tech Tips


      • A snapshot can be used to compare vehicle data from the time of the malfunction to normal data and is very useful for troubleshooting. The data in the list below is that of a normal vehicle, but as the data varies between individual vehicles, this data should only be used for reference.

      Result
      Proceed to
      NEXT

    NEXT

  20. CHECK SNAPSHOT (INJECTION FEEDBACK VAL #1 TO #4)


    1. Check Injection Feedback Val #1 to #4 in the snapshot taken when the engine was idling.

      Result
      Result Proceed to

      Injection Feedback Val for at least one cylinder is more than +3 mm3/st

      		 A
      Except above B

      Tech Tips


      • When there is a problem with the operation of an injector assembly due to foreign matter in the inside of the injector assembly, etc., the fuel injection volume decreases. As a result, the ECM gives instructions to increase the fuel injection volume, which causes Injection Feedback Val to increase.

      • The ECM controls the system so that the sum of Injection Feedback Val for all of the cylinders is approximately 0 mm3/st. Even if the value of Injection Feedback Val for a cylinder is less than -3.0 mm3/st (- 3.0 mm3/st is the lowest normal value), as long as the value of Injection Feedback Val for each of the other cylinders is 3.0 mm3/st or less, the injector assemblies are not malfunctioning.


    A

    GO TO STEP 8 Click here

    B

  21. READ VALUE USING GTS (MAP AND ATMOSPHERE PRESSURE)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine / Data List / MAP and Atmosphere Pressure.


      Powertrain > Engine > Data List
      Tester Display
      Atmosphere Pressure
      MAP

    4. Compare MAP to Atmosphere Pressure when the ignition switch is ON (do not start the engine).

      Standard
      Difference between MAP and Atmosphere Pressure is less than 8 kPa.

      Tech Tips


      • If MAP and Atmosphere Pressure have the same value, both are normal. If there is a difference of 8 kPa or more, compare the values to the atmospheric pressure for that day. The sensor whose deviation is the greatest is malfunctioning.

      • Standard atmospheric pressure is 101 kPa. For every 100 m increase in elevation, pressure drops by 1 kPa. This varies by weather.

      Result
      Result Proceed to
      MAP and Atmosphere Pressure have same value A
      MAP is different from actual atmospheric pressure B
      Atmosphere Pressure is different from actual atmospheric pressure C

    B

    REPLACE MANIFOLD ABSOLUTE PRESSURE SENSOR Click here

    C

    REPLACE ECM Click here

    A

  22. BASIC INSPECTION


    1. Check the fuel quality.

    2. Check the fuel for air.

    3. Check the fuel system for blockages.

    4. Check the air filter.

    5. Check the engine oil.

    6. Check the engine coolant.

    7. Check the engine idling speed and maximum engine speed.

    8. Check the vacuum pump.

      Result
      Proceed to
      NEXT

    NEXT

    END

  23. REPLACE FUEL SUPPLY PUMP ASSEMBLY (SUCTION CONTROL VALVE)


    1. Replace the fuel supply pump assembly.

      Click here

      Tech Tips

      If the common rail pressure becomes too high when transitioning due to problems with SCV operation, knocking noise worsens.

      Result
      Proceed to
      NEXT

    NEXT

  24. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system .

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  25. PERFORM FUEL SUPPLY PUMP INITIALIZATION


    1. Perform fuel supply pump initialization.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  26. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Check whether the knocking has been successfully repaired by starting the engine.

      Result
      Proceed to
      NEXT

    NEXT

    END