ECD SYSTEM(w/ Urea SCR System) Lack of Power or Hesitation

DESCRIPTION

Malfunction Condition Main Trouble Area Related Trouble Area

  • Lack of power caused by abnormal fuel injection volume (fuel supply pump assembly malfunction, injector assembly malfunction, etc.)

  • Lack of power caused by intake air volume shortage (turbocharger malfunction or exhaust manifold converter sub-assembly blocked)

(a) Injector assembly malfunctions


  • Injector sliding malfunction

  • Injector stuck closed

  • Injector stuck open

  • Deposits in injector

  • Injector circuit malfunction

(b) Abnormal common rail pressure


  • Pre-stroke control valve

(c) Abnormal intake air volume


  • Intake system leakage or clogged

  • Turbocharger sub-assembly

  • Exhaust manifold converter blockage

  • EGR valve does not close

  • Throttle valve does not open

  • Pressure discharge valve (P1271 stored simultaneously)

  • Intake air system blockage

  • EGR system

  • Fuel filter element assembly is clogged

  • Throttle valve

  • Mass air flow meter sub-assembly

  • Compression pressure

  • Injector compensation code

  • Fuel leak

  • Glow plug

  • Fuel pressure sensor

  • Manifold absolute pressure sensor

  • Vacuum hose connection for manifold absolute pressure sensor

  • Vehicle modifications

  • Clutch disc wear

  • Low quality fuel

  • Frozen 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 causing the malfunction.

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

  • This troubleshooting procedure checks for the cause of an obvious lack of engine power while the vehicle is being driven (such as the maximum speed being extremely low).


  1. Faults and Symptoms of Common Rail Diesel Components


    1. Engine Control

      Mass Air Flow Meter Sub-assembly
      Main fault Decrease in performance (foreign matter is stuck)
      Symptoms Lack of power, black smoke
      Data List MAF

      Tech Tips

      The maximum fuel injection volume is controlled according to the output from the mass air flow meter sub-assembly.
      Intake System
      Symptom and Corresponding Main Fault

      • Lack of power (no black smoke) due to air cleaner filter element blockage or crushed or leaking air duct

      • Black smoke (no lack of power) due to leakage between the turbo and intake manifold
      Data List

      • MAP

      • Target Booster Pressure

        When the accelerator is fully depressed, if MAP is 20 kPa lower than Target Booster Pressure for more than 5 seconds, then a lack of power will be felt.

      • MAF
      Turbocharger System
      Main fault

      • Air leak in the turbocharged air passage

      • Turbocharger sub-assembly (turbine, bearing, variable nozzle)
      Symptoms

      Lack of power (when vehicle is starting, under heavy load)

      (Black smoke is not emitted when racing while vehicle is stopped)
      Data List

      MAP, Target Booster Pressure


      • When the accelerator is fully depressed, if MAP is 20 kPa lower than Target Booster Pressure for more than 5 seconds, then a lack of power will be felt.

      • With the ignition switch ON or during idling, MAP = atmospheric pressure (standard atmospheric pressure = 101 kPa). When the engine speed is about 1500 rpm or more, the turbocharger starts to take effect and MAP becomes higher than atmospheric pressure.

      • Atmospheric pressure decreases by 1 kPa each time elevation increases by 100 m, and is also affected by the current weather conditions.
      Exhaust System
      Main fault Blockage
      Symptoms Lack of power (high engine speed, under heavy load)
      Data List

      MAP, Target Booster Pressure

      When the accelerator is fully depressed, if MAP is 20 kPa lower than Target Booster Pressure for more than 5 seconds, then a lack of power will be felt.
      Glow System
      Main fault Glow system malfunction
      Symptoms Difficult to start, rough idle, knocking, white smoke (when cold)
      Diagnostic Point

      • Measure the resistance of the glow plug

      • Check the glow plug indicator light
      Engine - 1
      Main fault Damaged, seized up
      Symptoms Cannot crank, crank speed is low, strange noise
      Engine - 2
      Main fault Loss of compression
      Symptoms Rough idle (lack of power always)
      Data List

      Engine Speed of Cyl#


      • When cranking during the "Check the Cylinder Compression" Active Test, if there is a high speed cylinder, approx. 100 rpm more than the other cylinders, that cylinder may lose compression.

      Injection Feedback Val


      • When an Injector Feedback Val is more than 3 mm3/st, there may be a malfunction in the corresponding cylinder.

    2. Diesel Injection

      Fuel Supply Pump Assembly
      Main fault -
      Symptoms Difficult to start, engine stalling, rough idle, lack of power
      Data List

      Common Rail Pressure, Target Common Rail Pressure


      • Common Rail Pressure is within 5000 kPa of Target Common Rail Pressure during idling with the engine warmed up (engine coolant temperature is higher than 75°C (167°F)).

      • If the fuel pressure is 20000 kPa below the target pressure, then a lack of power will be felt.

      • If the fuel pressure is below 25000 kPa, then idling will be rough.

      Tech Tips

      The fuel pressure changes at engine start, but is approx. 25000 kPa at engine start after the engine is warmed up.
      Diagnostic Trouble Code Even if Common Rail Pressure is below Target Common Rail Pressure, a DTC will not be stored.
      Fuel Filter Element Assembly
      Main fault Blockage
      Symptoms Difficult to start, engine stalling, rough idle, lack of power
      Data List

      Common Rail Pressure, Target Common Rail Pressure


      • Common Rail Pressure is within 5000 kPa of Target Common Rail Pressure during idling with the engine warmed up (engine coolant temperature is higher than 75°C (167°F)).

      • If the fuel pressure is 20000 kPa below the target pressure, then a lack of power will be felt.

      • If the fuel pressure is below 25000 kPa, then idling will be rough.

      Tech Tips

      The fuel pressure changes at engine start, but is approx. 25000 kPa at engine start after the engine is warmed up.
      Diagnostic Trouble Code Even if Common Rail Pressure is below Target Common Rail Pressure, a DTC will not be stored.
      Injector Assembly
      Main fault Blockage
      Symptoms Rough idle, lack of power, black smoke, white smoke, knocking
      Data List

      Injection Feedback Val


      • When an Injector Feedback Val is more than 3 mm3/st, there may be a malfunction in the corresponding cylinder. This value can be read after idling for 1 minute.
      Fuel Pressure Sensor
      Main fault Open circuit, decrease in performance (foreign matter is stuck)
      Symptoms Difficult to start, rough idle, engine stall, lack of power
      Data List

      Common Rail Pressure, Target Common Rail Pressure


      • Common Rail Pressure is within 5000 kPa of Target Common Rail Pressure during idling with the engine warmed up (engine coolant temperature is higher than 75°C (167°F)).
      Diagnostic Trouble Code When the fuel pressure sensor has a fault, some DTCs may be stored.
      Irregular Fuel
      Main fault -
      Symptoms Difficult to start, rough idle (especially when cold)

    3. Diesel EGR

      EGR System
      Main fault

      • Does not move smoothly

      • Does not close fully
      Symptoms

      • Rough idle

      • EGR valve stuck closed: A loud turbocharger sound.

      • EGR valve stuck open: Difficult to start (does not stall), black smoke, white smoke (when engine is cold), lack of power, jerking (If there is an excess in the quantity of EGR and there is a heavy load, when the vehicle starts moving, a lack of power will be felt. Also, when racing the engine, there will be some black smoke).
      Data List

      Actual EGR Valve Pos, Target EGR Valve Pos


      • Generally, Actual EGR Valve Pos = Target EGR Valve Pos +/-5% (fully closed: 0%, fully open: 100%).

      • Using the EGR valve Active Test, check whether Actual EGR Valve Pos follows Target EGR Valve Pos (the engine coolant temperature and intake air temperature should be considered when a malfunction occurs).

      • EGR valve is fully closed when the ignition switch is ON (engine stopped).

      • EGR valve opens to the halfway point at idling after the engine is warmed up.

      • When the EGR valve does not close, MAF (Mass Air Flow) decreases when the vehicle is accelerated at full throttle. MAP also decreases in comparison to Target Booster Pressure, however there is not a large difference.

      EGR Close Lrn. Val.


      • When leaving the vehicle idling, the normal range of EGR Close Lrn. Val. is 0 to 1 V.

      • In cases when EGR Close Lrn. Val. is out of the normal range (0 to 1 V), it is possible that the EGR valve cannot completely close.

    4. Diesel Throttle

      Diesel Throttle System
      Main fault Stuck, does not move smoothly
      Symptoms

      • Stuck closed: Lack of power, difficult to start, rough idle, engine stall, black smoke. These may occur when stuck almost fully closed.

      • Stuck open: Turbocharger sound increases. When the engine is stopped, engine vibrations may occur.
      Data List

      Actual Throttle Position


      • 0%: Fully closed

      • 100%: Fully open

      • When the ignition switch is ON (engine stopped), the diesel throttle is fully open. When idling, the diesel throttle is at the halfway point. When the ignition switch is turned from ON to off, the throttle is fully closed temporarily.

  2. Data List Related to Lack of Power


    • Engine Speed

    • MAP

    • MAF

    • Intake Air

    • Coolant Temp

    • Target Common Rail Pressure

    • Common Rail Pressure

    • Injection Feedback Val #1 (to #4)

    • Injection Volume

    • Actual Throttle Position

    • Target EGR Valve Pos

    • Actual EGR Valve Pos

CAUTION / NOTICE / HINT


  1. Explanation of Symptom

    Lack of Power

    The power of the diesel engine is determined by the quantity of injected fuel and the quantity of intake air.

    The quantity of injected fuel is determined by the fuel pressure and the amount of time the injector assembly is open. Basically, the fuel pressure is controlled so that it reaches the target fuel pressure. The throttle valve does not restrict air flow volume, so the manifold absolute pressure is almost the same as atmospheric pressure when idling. At more than approximately 1500 rpm, the turbo starts to operate causing the manifold absolute pressure to become higher than atmospheric pressure.

    The manifold absolute pressure is controlled so that it reaches the Target Booster Pressure when accelerating the vehicle at full throttle. Also, when accelerating the vehicle at full throttle, the throttle is fully open and the EGR valve is fully closed, preserving the mass air flow.

    Note

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

PROCEDURE


  1. 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.

    4. Read the pending DTCs.


      Powertrain > Engine > Trouble Codes
      Result
      Result Proceed to
      No DTC is output A
      Engine related DTCs are output B

      Tech Tips

      If only DTC P1608 is output, proceed to step 2.


    B

    GO TO DTC CHART Click here

    A

  2. TAKE SNAPSHOT DURING IDLING AND 4000 RPM (PROCEDURE 2)


    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 / Diesel Lack of Power.

    4. With no load after the engine is warmed up, take a snapshot when idling and at 4000 rpm.

      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 shift lever should be in neutral and the A/C switch and all accessory switches should be off.

      Result
      Proceed to
      NEXT

    NEXT

  3. TAKE SNAPSHOT DURING LACK OF POWER (PROCEDURE 3)


    1. Enter the following menus: Powertrain / Engine / Data List / Diesel Lack of Power.

    2. Check for a lack of power during the driving test.

      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.

      • Move the shift lever to 2nd gear and accelerate the vehicle with the accelerator pedal fully depressed. Then, check the Data List with the engine warmed up and idling (the shift lever should be in neutral and the A/C switch and all accessory switches should be off).

      Note

      Obey all laws and regulations, and pay attention to traffic conditions while driving the vehicle.

      Result
      Result Proceed to
      Apparent lack of power is present A
      Apparent lack of power is not present B

    B

    COMPARE WITH SIMILAR VEHICLE WITH SAME ENGINE Click here

    A

  4. CHECK SNAPSHOT (MAP AND MAF)


    1. Check MAP and MAF in the snapshot taken in procedure 2 when the engine was running at 4000 rpm with no load.

      Result
      Result Proceed to
      MAF 84 gm/sec or more and MAP 105 kPa or higher*1 A
      MAP is below 90 kPa*2 B
      Except above*3 C

      Tech Tips

      The above values were measured under standard atmospheric pressure. The values are influenced by elevation, weather conditions, etc.

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

      *1: There may be a problem in the fuel injection system or intake system.

      *2: There may be a problem in the turbocharger system.

      *3: There may be a problem in the intake system or a problem with the EGR valve (valve stuck open or valve does not close).


    B

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

    C

    CHECK INTAKE SYSTEM Click here

    A

  5. CHECK SNAPSHOT (MAP, COMMON RAIL PRESSURE AND TARGET COMMON RAIL PRESSURE)


    1. Check MAP, Common Rail Pressure and Target Common Rail Pressure in the snapshot taken in procedure 3 when the vehicle was accelerating with the accelerator pedal fully depressed in 2nd gear.

      Result
      Result Proceed to
      MAP is below 190 kPa at an engine speed of 3000 rpm A
      Difference between Common Rail Pressure and Target Common Rail Pressure is 20000 kPa or more B
      Except above C

      Tech Tips


      • The above values were measured under standard atmospheric pressure. The values are influenced by elevation, weather conditions, etc. Standard atmospheric pressure is 101 kPa. For every 100 m increase in elevation, pressure drops by 1 kPa. This varies by weather.

      • The engine speed must be 1500 rpm or less before performing the inspection in which the accelerator pedal is fully depressed and the engine is accelerated to a speed of 3000 rpm.

      • If the turbocharger movement is not smooth, etc., the value of MAP in the snapshot taken during lack of power will not reach the target value. When the accelerator pedal is fully depressed and the engine speed is 3000 rpm, the MAP should be higher than 190 kPa.


    B

    INSPECT CLOGGED FUEL PIPE Click here

    C

    GO TO STEP 26 Click here

    A

  6. CHECK INTAKE SYSTEM


    1. Check for air leaks and blockages between the air cleaner case and turbocharger sub-assembly, and between the turbocharger sub-assembly and intake manifold.

      Tech Tips


      • Inspect the intake system, especially hoses and pipes between the air cleaner filter element sub-assembly and turbocharger sub-assembly.

      • Check for abnormal disconnections, pipe and hose squashing, and any damage in the intake system.

      • Using your hand, check whether the pipes and hoses in the intake system are securely connected.

      • By applying soapy water and revving up the engine, air leaks from the intake system can be checked by checking for bubbles.

      • Check for any modifications in the intake system made by the user.

      OK
      No leakage or blockage.
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE INTAKE SYSTEM Click here

    OK

  7. CLEAN FUEL FILTER CASE AND REPLACE FUEL FILTER ELEMENT ASSEMBLY


    1. Clean the fuel filter case and replace the fuel filter element assembly.

      Click here

      Tech Tips

      Be sure to clean the inside of the fuel filter case as the injector assemblies may not operate properly if the fuel filter element assembly is installed with foreign matter remaining inside the fuel filter case.

      Result
      Proceed to
      NEXT

    NEXT

  8. REPLACE INJECTOR ASSEMBLIES OF ALL CYLINDERS


    1. Replace the injector assemblies of all cylinders.

      Click here

      Note


      • When replacing the injector assembly for a cylinder, always be sure to use a new No. 1 injection pipe sub-assembly and a new No. 2 injection pipe sub-assembly.

      • Follow the procedure in the repair manual and temporarily install the No. 1 injection pipe sub-assembly, No. 2 injection pipe sub-assembly and No. 1 nozzle leakage pipe assembly, 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 sub-assembly may become incomplete, resulting in a fuel leak.

      Result
      Proceed to
      NEXT

    NEXT

  9. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  10. REGISTER INJECTOR COMPENSATION CODE AND PERFORM PILOT QUANTITY LEARNING


    1. Register the injector compensation code.

      Click here


      Powertrain > Engine > Utility
      Tester Display
      Injector Compensation

    2. Perform the injector pilot quantity learning.

      Click here


      Powertrain > Engine > Utility
      Tester Display
      Pilot Quantity Learning
      Result
      Proceed to
      NEXT

    NEXT

  11. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

    Result
    Proceed to
    NEXT

    NEXT

    END

  12. COMPARE WITH SIMILAR VEHICLE WITH SAME ENGINE


    1. Confirm the situation in which the lack of power was experienced by the customer again, and compare the driving feeling under the same conditions using a similar vehicle with the same engine while collecting data with the GTS.

      Tech Tips

      Confirm the state of the following conditions when the lack of power was experienced.


      • Accelerator pedal position (vehicle load)

      • Vehicle speed

      • Engine coolant temperature

      • Ambient temperature

      • Driving conditions before the lack of power occurred

      • Climate

      • Road and traffic conditions

      • When (what day) the problem was noticed

      • Whether the problem occurs suddenly or gradually

      • How often the problem occurs

      • Why the customer felt there is a lack of power (e.g. the customer compared their vehicle with another vehicle, somebody told the customer that their vehicle has a lack of power, etc.)

      • Level of lack of power (slight or drastic)

      Result
      Result Proceed to
      Significant difference is found A
      Significant difference is not found B

    A

    GO TO STEP 4 Click here

    B

    EXPLAIN THE INVESTIGATION RESULT TO CUSTOMER Click here

  13. READ VALUE USING GTS (ATMOSPHERIC PRESSURE AND MAP)


    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 / Atmosphere Pressure and MAP.


      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

  14. CHECK INTAKE SYSTEM


    1. Check for air leaks and blockages between the air cleaner cap and turbocharger sub-assembly, and between the turbocharger sub-assembly and intake manifold.

      Result
      Result Proceed to
      Leaks and/or blockages exist in the intake system A
      No leaks or blockages in the intake system B

      Tech Tips


      • Inspect the intake system, especially hoses and pipes between the air cleaner filter element sub-assembly and turbocharger sub-assembly.

      • Check for abnormal disconnections, pipe and hose squashing, and any damage in the intake system.

      • Using your hand, check whether the pipes and hoses in the intake system are securely connected.

      • When inspecting for a clogged intake system (cause of low MAP), check the following points:


        • - Clogged air cleaner filter element

        • - Clogged intake hose

        • - Diesel throttle valve stuck in closed position

      • Check for any modifications in the intake system made by the user.


    B

    CHECK LACK OF POWER (TURBOCHARGER SYSTEM) Click here

    A

  15. REPAIR OR REPLACE INTAKE SYSTEM


    1. Repair or replace the malfunctioning part in the intake system.

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 18 Click here

  16. EXPLAIN THE INVESTIGATION RESULT TO CUSTOMER


    1. Vehicle performance is normal. There is no problem at this point in time. However, if the problem reoccurs, ask the customer to explain in detail the situation in which the problem occurred. The best course may be to have the customer ride in another vehicle with the same specifications to understand that there is no problem with the customer's vehicle.

      Result
      Proceed to
      NEXT

    NEXT

    END

  17. CHECK LACK OF POWER (TURBOCHARGER SYSTEM)


    1. Check the lack of power (turbocharger system).

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  18. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

    Result
    Proceed to
    NEXT

    NEXT

    END

  19. INSPECT CLOGGED FUEL PIPE


    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 / Target Common Rail Pressure and Common Rail Pressure.


      Powertrain > Engine > Data List
      Tester Display
      Target Common Rail Pressure
      Common Rail Pressure

    4. With no load after the engine is warmed up, take a snapshot when idling and vehicle was accelerating with the accelerator pedal fully depressed in 2nd gear.

    5. Check the Target Common Rail Pressure and Common Rail Pressure value.

      B0025O8E04
      Result
      Result Proceed to
      While idling the vehicle, "Common Rail Pressure" deviates from the normal range and varies periodically with a period of approximately 2 seconds or more*1 A
      "Common Rail Pressure" is normal while idling the vehicle, but "Common Rail Pressure" does not follow "Target Common Rail Pressure" when the accelerator pedal is fully depressed in 2nd gear*2
      Except above B

      Note


      • *1: The cause may be a squashed or blocked fuel pipe or hose.

      • *2: The cause may be a clogged fuel filter element assembly.


    B

    REPLACE FUEL SUPPLY PUMP ASSEMBLY Click here

    A

  20. REPAIR OR REPLACE CLOGGED FUEL LINE


    1. Repair or replace the clogged (including frozen fuel) fuel pipe.

    2. Replace the fuel filter element assembly.

      Click here

      Tech Tips

      If "Common Rail Pressure" does not follow "Target Common Rail Pressure" when the accelerator pedal is fully depressed in 2nd gear, replace the fuel filter element assembly.

      Result
      Proceed to
      NEXT

    NEXT

  21. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  22. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    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 / Test the Fuel Leak / Data List / Target Common Rail Pressure and Common Rail Pressure.


      Powertrain > Engine > Active Test
      Active Test Display
      Test the Fuel Leak
      Data List Display
      Target Common Rail Pressure
      Common Rail Pressure

    4. Take a snapshot with the GTS during the Active Test.

    5. Measure the difference between the target fuel pressure (Target Common Rail Pressure) and the actual fuel pressure (Common Rail Pressure) when the "Test the Fuel Leak" Active Test is performed.

      Tech Tips

      In order to obtain an exact measurement, perform the Active Test 5 times and measure the difference once each time the Active Test is performed.

      B0027UBE55
      OK
      The difference between the target fuel pressure and the actual fuel pressure 2 seconds after the Active Test starts is less than 10000 kPa.

      Tech Tips


      • "Target Common Rail Pressure" is the target fuel pressure controlled by the ECM.

      • "Common Rail Pressure" is the actual fuel pressure.

      Result
      Proceed to
      NEXT

    NEXT

    END

  23. REPLACE FUEL SUPPLY PUMP ASSEMBLY


    1. Replace the fuel supply pump assembly.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 21 Click here

  24. REPLACE MANIFOLD ABSOLUTE PRESSURE SENSOR


    1. Replace the manifold absolute pressure sensor.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 18 Click here

  25. REPLACE ECM


    1. Replace the ECM.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 18 Click here

  26. CHECK INTAKE SYSTEM


    1. Check for air leaks and blockages between the air cleaner cap and turbocharger sub-assembly, and between the turbocharger sub-assembly and intake manifold.

      Result
      Result Proceed to
      No leaks or blockages in the intake system A
      Leaks and/or blockages exist in the intake system B

      Tech Tips


      • Inspect the intake system, especially hoses and pipes between the air cleaner filter element sub-assembly and turbocharger sub-assembly.

      • Check for abnormal disconnections, pipe and hose squashing, and any damage in the intake system.

      • Using your hand, check whether the pipes and hoses in the intake system are securely connected.

      • By applying soapy water and revving up the engine, air leaks from the intake system can be checked by checking for bubbles.

      • Make sure that the hose between the manifold absolute pressure sensor and intake manifold is not loose or disconnected.

      • Check for any modifications in the intake system made by the user.


    B

    REPAIR OR REPLACE INTAKE SYSTEM Click here

    A

  27. PERFORM ACTIVE TEST USING GTS (ACTIVATE THE EGR VALVE CLOSE)


    1. Connect the GTS to the DLC3.

    2. Start the engine and warm it up, and make sure the A/C switch and all accessory switches are off.

    3. Turn the ignition switch off. Wait for 30 seconds, and then restart the engine.

    4. Turn the GTS on.

    5. Enter the following menus: Powertrain / Engine / Data List / MAF.


      Powertrain > Engine > Data List
      Tester Display
      MAF

    6. Read the MAF value displayed on the GTS while the engine is idling.

    7. Enter the following menus: Powertrain / Engine / Active Test / Activate the EGR Valve Close / Data List / MAF.


      Powertrain > Engine > Active Test
      Active Test Display
      Activate the EGR Valve Close
      Data List Display
      MAF

    8. Read the MAF value when the EGR valve is closed using the Active Test function.

      Tech Tips


      • If idling continues for 20 minutes or more, the EGR valve target opening angle becomes 0% (EGR valve fully closed). As this makes diagnosis impossible, it becomes necessary to drive the vehicle or restart the engine.

      • Before performing the diagnosis, confirm that the EGR valve target opening angle is not 0%.

      Result
      Active Test Result Proceed to

      Activate the EGR Valve Close:

      Off (Open) to On (Closed)

      		 MAF value does not change A
      MAF value changes B

      Note

      As the measured values may differ from those shown below due to factors such as differences in measuring environments and changes in vehicle condition due to aging, do not use these values to determine whether the vehicle is malfunctioning or not.

      Tech Tips

      The problem may be a temporary one, due to the entry of deposits or foreign matter. Check that there are no deposits or foreign matter in the electric EGR control valve assembly or mass air flow meter sub-assembly.

      Reference
      EGR Valve Condition (Opening) Measuring Condition MAF (Reference)
      Open (50%)

      • Atmospheric pressure: 101 kPa

      • Engine coolant temperature: 75°C (167°F)

      		 3 to 10 gm/sec
      Closed (0%) 12 to 18 gm/sec

    B

    PERFORM ACTIVE TEST USING GTS (ACTIVATE THE VSV FOR EGR COOLER BYPASS) Click here

    A

  28. READ VALUE USING GTS (ENGINE SPEED AND MAF)


    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 / Engine Speed and MAF.


      Powertrain > Engine > Data List
      Tester Display
      Engine Speed
      MAF

    4. Start the engine and read the value when 30 seconds has elapsed.

      Standard
      Engine Speed MAF
      Idling

      • 2 to 17 gm/sec (EGR on)

      • 13 to 20 gm/sec (EGR off)
      3000 rpm (without load)

      • 36 to 67 gm/sec (EGR on)

      • 63 to 72 gm/sec (EGR off)
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE MASS AIR FLOW METER SUB-ASSEMBLY Click here

    OK

  29. PERFORM ACTIVE TEST USING GTS (ACTIVATE THE VSV FOR EGR COOLER BYPASS)


    1. Connect the GTS to the DLC3.

    2. Start the engine and warm it up, and make sure the A/C switch and all accessory switches are off.

    3. Turn the ignition switch off and wait for 30 seconds.

    4. Start the engine and turn the GTS on.

    5. Enter the following menus: Powertrain / Engine / Data List / MAF.


      Powertrain > Engine > Data List
      Tester Display
      MAF

    6. Read the MAF value displayed on the GTS while the engine is idling.

    7. Enter the following menus: Powertrain / Engine / Active Test / Activate the VSV for EGR Cooler Bypass / Data List / MAF and EGR Cooler Bypass Position.

      Tech Tips

      Whether the EGR is passing through the bypass side or cooler side during the Active Test can be confirmed by checking EGR Cooler Bypass Position.


      Powertrain > Engine > Active Test
      Active Test Display
      Activate the VSV for EGR Cooler Bypass
      Data List Display
      MAF
      EGR Cooler Bypass Position

    8. Using the Active Test function, switch the EGR cooler bypass valve between "Cooler" and "Bypass" a few times, and then check whether the MAF value changes after switching the valve from "Cooler" to "Bypass".

      Tech Tips


      • If idling continues for 20 minutes or more, the EGR valve target opening angle becomes 0% (EGR valve fully closed). As this makes diagnosis impossible, it becomes necessary to drive the vehicle or restart the engine.

      • When operating "Activate the VSV for EGR Cooler Bypass", check that "Cooler" and "Bypass" can be switched between and the EGR cooler by-pass valve regulating link operates. If the link does not operate, the inspection cannot be performed correctly. Therefore, inspect and repair the following parts, perform the Active Test and read the changes in the MAF value.

        - No. 2 EGR valve assembly

        Click here

        - Vacuum hose connection

        Click here

        - Vacuum switching valve assembly (for EGR Bypass Valve)

        Click here

      Result
      GTS Display Result Proceed to

      Activate the VSV for EGR Cooler Bypass:

      Cooler to Bypass

      		 MAF value does not change A
      MAF value changes B

      Tech Tips

      If the EGR cooler is clogged, the mass air flow changes.


    B

    REPLACE NO. 1 EGR COOLER Click here

    A

  30. CHECK FOR DEPOSIT (ELECTRIC EGR CONTROL VALVE ASSEMBLY)


    1. Remove the electric EGR control valve assembly.

      Click here

    2. Visually check the electric EGR control valve assembly for deposits. If there are deposits, clean the electric EGR control valve assembly.

      Note


      • When cleaning the electric EGR control valve, make sure the valve is completely closed.

      • Do not forcibly open the valve, as it may be damaged or deformed.

      • When cleaning the electric EGR control valve, use a piece of cloth soaked with cleaning solvent. Spraying the solvent directly onto these parts or soaking the parts in the solvent may damage the parts.

      • When cleaning the electric EGR control valve, care should be taken to prevent the ingress of cleaning solvent into the bearings of the valve shaft, and when wiping off deposits on the EGR valve, care should be taken not to push the deposits into the bearings of the valve shaft. These contaminants may adversely affect the function of the EGR valve.

      • When cleaning the electric EGR control valve assembly, perform the initialization procedure.

        Click here

      Tech Tips


      • If the EGR valve does not open properly or is stuck closed, the amount of intake air increases and combustion sounds and engine vibration may increase.

      • If the EGR valve does not close properly or is stuck open, EGR becomes excessive and combustion becomes unstable. Also, there may be a lack of power. In this case, clean the electric EGR control valve assembly.

    3. Reinstall the electric EGR control valve assembly.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 33 Click here

  31. REPAIR OR REPLACE INTAKE SYSTEM


    1. Repair or replace the malfunctioning part in the intake system.

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 33 Click here

  32. REPLACE NO. 1 EGR COOLER


    1. Replace the No. 1 EGR cooler.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  33. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

    Result
    Proceed to
    OK
    NG

    OK

    END

    NG

    GO TO STEP 36 Click here

  34. REPLACE MASS AIR FLOW METER SUB-ASSEMBLY


    1. Replace the mass air flow meter sub-assembly.

      Click here

      Tech Tips


      • If foreign matter is stuck inside the mass air flow meter sub-assembly, the output characteristics of the mass air flow meter sub-assembly may change, resulting in a malfunction.

      • Before replacing the mass air flow meter sub-assembly, perform a wire harness inspection and if there are any problems with the wire harness, repair or replace it.

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 33 Click here

  35. PERFORM ACTIVE TEST USING GTS (ACTIVATE THE VSV FOR EGR COOLER BYPASS)


    1. Connect the GTS to the DLC3.

    2. Start the engine and warm it up, and make sure the A/C switch and all accessory switches are off.

    3. Turn the ignition switch off and wait for 30 seconds.

    4. Start the engine and turn the GTS on.

    5. Enter the following menus: Powertrain / Engine / Data List / MAF.


      Powertrain > Engine > Data List
      Tester Display
      MAF

    6. Read the MAF value displayed on the GTS while the engine is idling.

    7. Enter the following menus: Powertrain / Engine / Active Test / Activate the VSV for EGR Cooler Bypass / Data List / MAF and EGR Cooler Bypass Position.

      Tech Tips

      Whether the EGR is passing through the bypass side or cooler side during the Active Test can be confirmed by checking EGR Cooler Bypass Position.


      Powertrain > Engine > Active Test
      Active Test Display
      Activate the VSV for EGR Cooler Bypass
      Data List Display
      MAF
      EGR Cooler Bypass Position

    8. Using the Active Test function, switch the EGR cooler bypass valve between "Cooler" and "Bypass" a few times, and then check whether the MAF value changes after switching the valve from "Cooler" to "Bypass".

      Tech Tips


      • If idling continues for 20 minutes or more, the EGR valve target opening angle becomes 0% (EGR valve fully closed). As this makes diagnosis impossible, it becomes necessary to drive the vehicle or restart the engine.

      • When operating "Activate the VSV for EGR Cooler Bypass", check that "Cooler" and "Bypass" can be switched between and the EGR cooler by-pass valve regulating link operates. If the link does not operate, the inspection cannot be performed correctly. Therefore, inspect and repair the following parts, perform the Active Test and read the changes in the MAF value.

        - No. 2 EGR valve assembly

        Click here

        - Vacuum hose connection

        Click here

        - Vacuum switching valve assembly (for EGR Bypass Valve)

        Click here

      Result
      GTS Display Result Proceed to

      Activate the VSV for EGR Cooler Bypass:

      Cooler to Bypass

      		 MAF value does not change A
      MAF value changes B

      Tech Tips

      If the EGR cooler is clogged, the mass air flow changes.


    B

    REPLACE NO. 1 EGR COOLER Click here

    A

  36. CHECK EXHAUST MANIFOLD CONVERTER SUB-ASSEMBLY


    1. Remove the exhaust manifold converter sub-assembly.

      Click here

    2. Visually check for catalyst clogging or carbon deposits adhering to the inner wall of the exhaust pipe upstream of the catalyst.

      OK
      Less than 10% of the cells are clogged.

    3. Reinstall the exhaust manifold converter sub-assembly.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE EXHAUST MANIFOLD CONVERTER SUB-ASSEMBLY Click here

    OK

  37. CHECK LACK OF POWER (TURBOCHARGER SYSTEM)


    1. Check the lack of power (turbocharger system).

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  38. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

    Result
    Proceed to
    NEXT

    NEXT

    END

  39. REPLACE EXHAUST MANIFOLD CONVERTER SUB-ASSEMBLY


    1. Replace the exhaust manifold converter sub-assembly.

      Click here

      Note

      Perform the initialization procedure for DPF catalyst record clear.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 38 Click here

  40. REPLACE NO. 1 EGR COOLER


    1. Replace the No. 1 EGR cooler.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 38 Click here