ECD 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 front exhaust pipe or exhaust manifold converter 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


  • Suction control valve

(c) Abnormal intake air volume


  • Intake air system leakage or clogged

  • Turbocharger

  • Front exhaust pipe blockage

  • 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 sub-assembly is clogged

  • Throttle valve

  • Mass air flow meter

  • Compression pressure

  • Injector compensation code

  • Fuel leak

  • Glow plug

  • Fuel pressure sensor

  • Manifold absolute pressure sensor

  • Vacuum hose connection for manifold absolute pressure sensor

  • Injector driver (P0200 stored simultaneously)

  • 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
      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.
      Intake System
      Symptom and Corresponding Main Fault

      • Lack of power (no black smoke) due to air filter 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 (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 Open circuit, glow plug relay fault
      Symptoms Difficult to start, rough idle, knocking, white smoke (when cold)
      Data List Check the glow plug indicator light
      Diagnostic Point Measure the resistance of the glow plug
      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, Target Pump SCV Current


      • In a stable condition (e.g. idling), Common Rail Pressure is within 5000 kPa of "Target Common Rail Pressure".

      • 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.

      • If Target Pump SCV Current is 3000 mA or higher, the suction control valve may be stuck.

      Tech Tips


      • The fuel pressure changes at engine start, but is approx. 25000 kPa at engine start after the engine is warmed up.

      • When Target Pump SCV Current is 3000 mA or higher, the suction control valve has a tendency to become stuck.
      Diagnostic Trouble Code Even if Common Rail Pressure is below Target Common Rail Pressure, a DTC will not be stored.
      Fuel Filter Element Sub-assembly
      Main fault Blockage
      Symptoms Difficult to start, engine stalling, rough idle, lack of power
      Data List

      Common Rail Pressure, Target Common Rail Pressure


      • In a stable condition (e.g. idling), the fuel pressure is within 5000 kPa of "Target Common Rail Pressure".

      • 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 with the engine warmed up (engine coolant temperature is higher than 70°C (158°F)).
      Injector Driver
      Main fault Circuit fault: The injector assembly does not open.
      Symptoms Difficult to start, rough idle, lack of power, black smoke, white smoke, knocking
      Data List Same as injector assembly
      Diagnostic Trouble Code When the injector driver has a fault, some DTCs may be stored.
      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


      • In a stable condition (e.g. idling), Common Rail Pressure is within 5000 kPa of "Target Common Rail Pressure".
      Diagnostic 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 Position


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

      • Using the EGR valve Active Test, check whether Actual EGR Valve Pos. follows Target EGR Position (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., EGR Close Lrn. Status


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

      • In cases when EGR Close Lrn. Status. is NG or 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 (fully closed: 0%, fully open: 100%)

      • 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

    • Target Pump SCV Current

    • Injection Feedback Val #1 (to #4)

    • Injection Volume

    • Actual Throttle Position

    • Target EGR Position

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

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

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

PROCEDURE


  1. READ OUTPUT DTC (RELATING TO ENGINE)


    1. Connect the intelligent tester to the DLC3.

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

    3. Enter the following menus: Powertrain / Engine and ECT / DTC.

    4. Read pending DTCs.

      Result
      Result Proceed to
      No DTCs are output A
      Engine related DTCs are output B

    B

    GO TO DTC CHART Click here

    A

  2. TAKE SNAPSHOT DURING IDLING AND 4000 RPM


    1. B001D63E02
      *1 Snapshot Button

      Connect the intelligent tester to the DLC3.

    2. Start the engine and turn the tester on.

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

    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.

      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.


    NEXT

  3. TAKE SNAPSHOT DURING LACK OF POWER


    1. B001D63E02
      *1 Snapshot Button

      Connect the intelligent tester to the DLC3.

    2. Start the engine and turn the tester on.

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

    4. Take a snapshot of the following Data List items with the intelligent tester during lack of power.

      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 (obey all laws and regulations, and pay attention to traffic conditions while driving the vehicle). 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).

      Tech Tips


      • Examples of actual malfunctions (See "Diagnostic Help" menu):


        • Lack of power caused by overly low boost pressure

        • Lack of power caused by overly low MAF

        • EGR valve stuck in open position

      • For engine protection, exhaust gas or fuel economy related reasons, there are some ranges of engine operation where engine power feels like it flattens out, but this is not a malfunction.

      • 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.

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

      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 when the engine was running at 4000 rpm with no load.

      Result
      Result Proceed to
      MAP is 114 kPa or higher and MAF is 84 g/sec. or more*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.

      *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 INTELLIGENT TESTER (MAP AND ATMOSPHERIC PRESSURE) Click here

    C

    CHECK AIR INTAKE SYSTEM Click here

    A

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


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

      Result
      Result Proceed to
      MAP is below 205 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 205 kPa.


    B

    BLEED AIR FROM FUEL SYSTEM Click here

    C

    CHECK AIR INTAKE SYSTEM Click here

    A

  6. CHECK INTAKE SYSTEM


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

      Tech Tips


      • Inspect the air intake system, especially hoses and pipes between the air cleaner and turbocharger.

      • 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.

    NG

    REPAIR OR REPLACE AIR INTAKE SYSTEM Click here

    OK

  7. REPLACE FUEL FILTER ELEMENT SUB-ASSEMBLY


    1. Replace the fuel filter element sub-assembly.


    NEXT

  8. REPLACE INJECTOR ASSEMBLIES OF ALL CYLINDERS


    1. Replace the injector assemblies Click here.


    NEXT

  9. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system Click here.


    NEXT

  10. REGISTER INJECTOR COMPENSATION CODE AND PERFORM PILOT QUANTITY LEARNING


    1. Register the injector compensation code Click here.

    2. Perform the injector pilot quantity learning Click here.


    NEXT

  11. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    NEXT

    END

  12. READ VALUE USING INTELLIGENT TESTER (MAP AND ATMOSPHERIC PRESSURE)


    1. Connect the intelligent tester to the DLC3.

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

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

    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

  13. CHECK AIR INTAKE SYSTEM


    1. Check for air leaks and blockages between the air cleaner case and turbocharger, and between the turbocharger 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 air intake system, especially hoses and pipes between the air cleaner and turbocharger.

      • 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

        • Clogged intake hose

        • Diesel throttle valve stuck in closed position

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


    B

    REPLACE TURBOCHARGER SUB-ASSEMBLY Click here

    A

  14. REPAIR OR REPLACE AIR INTAKE SYSTEM


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


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  15. REPLACE TURBOCHARGER SUB-ASSEMBLY


    1. Replace the turbocharger sub-assembly Click here.


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  16. REPLACE MANIFOLD ABSOLUTE PRESSURE SENSOR


    1. Replace the manifold absolute pressure sensor Click here.


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  17. REPLACE ECM


    1. Replace the ECM Click here.


    NEXT

  18. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    NEXT

    END

  19. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system Click here.


    NEXT

  20. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (TEST THE FUEL LEAK)


    1. Connect the intelligent tester to the DLC3.

    2. Start the engine and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Active Test / Test the Fuel Leak / Data List / Common Rail Pressure, Target Common Rail Pressure.

    4. B001D63E02
      *1 Snapshot Button

      Take a snapshot with the intelligent tester during the Active Test.

      Tech Tips

      Detailed graphs can be displayed by transferring the stored snapshot from the tester to a PC (personal computer) with Intelligent Viewer installed.

    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.

      B001E8EE01
      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.


    OK

    END

    NG

  21. CHECK IF FUEL IS BEING SUPPLIED TO FUEL SUPPLY PUMP ASSEMBLY


    1. Disconnect the inlet hose from the fuel supply pump assembly.

    2. Operate the priming pump and check that fuel is being supplied to the fuel supply pump assembly.

      OK
      Fuel is properly supplied to the fuel supply pump assembly when the priming pump is operated.

      Tech Tips


      • When there is a lack of fuel, the fuel pressure drops.

      • Inspect for fuel filter element sub-assembly clogging.

    3. Reconnect the inlet hose.


    NG

    REPAIR OR REPLACE CLOGGED FUEL PIPE (INCLUDING FROZEN FUEL) (FUEL TANK - FUEL SUPPLY PUMP) Click here

    OK

  22. REPLACE SUCTION CONTROL VALVE


    1. Replace the suction control valve Click here.


    NEXT

    BLEED AIR FROM FUEL SYSTEM Click here

  23. REPAIR OR REPLACE CLOGGED FUEL PIPE (INCLUDING FROZEN FUEL) (FUEL TANK - FUEL SUPPLY PUMP)


    1. Check and repair or replace the clogged fuel pipe.


    NEXT

  24. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system Click here.


    NEXT

  25. PERFORM FUEL SUPPLY PUMP INITIALIZATION


    1. Perform fuel supply pump initialization Click here.


    NEXT

  26. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the intelligent tester to the DLC3.

    2. Start the engine and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Active Test / Test the Fuel Leak / Data List / Common Rail Pressure, Target Common Rail Pressure.

    4. B001D63E02
      *1 Snapshot Button

      Take a snapshot with the intelligent tester during the Active Test.

      Tech Tips

      Detailed graphs can be displayed by transferring the stored snapshot from the tester to a PC (personal computer) with Intelligent Viewer installed.

    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.

      B001E8EE01
      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.


    NEXT

    END

  27. CHECK AIR INTAKE SYSTEM


    1. Check for air leaks and blockages between the air cleaner case and turbocharger, and between the turbocharger 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 air intake system, especially hoses and pipes between the air cleaner and turbocharger.

      • 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 AIR INTAKE SYSTEM Click here

    A

  28. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (ACTIVATE THE VSV FOR EGR CUT)


    1. Connect the intelligent tester 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 tester on.

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

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

    7. Enter the following menus: Powertrain / Engine and ECT / Active Test / Activate the VSV for EGR Cut or Activate the EGR valve Close.

    8. Read the mass air flow meter value when the VSV for EGR Cut or electric vacuum regulating valve assembly is turned from off to on using the Active Test function.

      Tech Tips


      • If idling continues for 15 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 to restart the engine.

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

      • When "Coolant Temp" is 75°C (167°F) or higher during idling, the exhaust gas flows through the EGR cooler. If MAF does not change when the EGR is cut even though the EGR valve is operating normally, the EGR cooler may be clogged.

      • When idling while warming up the engine, the actuator operates and the EGR cooler is bypassed. However, if the connector of the VSV for the EGR cooler is disconnected, the EGR cooler is not bypassed and it is possible to check how clogged the EGR cooler is.

      Result
      Active Test Result Proceed to

      Activate the VSV for EGR Cut:

      Off (Open) to on (Close)

      		 MAF value does not change A
      MAF value changes B

      Note

      As the values shown below may differ 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 vacuum regulating valve assembly or mass air flow meter.

      Reference
      EGR Valve Condition (Opening) Measuring Condition MAF (Reference)
      Open (55%)

      • Atmosphere pressure: 101 kPa

      • Intake air temperature: 30°C (86°F)

      • Engine coolant temperature: 88°C (190°F)

      		 4.5 to 10.5 g/sec
      Close (0%) 13 to 20 g/sec

    B

    READ VALUE USING INTELLIGENT TESTER (MAF) Click here

    A

  29. READ VALUE USING INTELLIGENT TESTER (MAF)


    1. Connect the intelligent tester to the DLC3.

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

    3. Enter the following menus: Powertrain / Engine and ECT / Data List / MAF.

    4. Read the value.

      Standard
      Tester Display Condition Specified Condition
      MAF Engine not running Less than 0.3 g/sec

    NG

    REPLACE MASS AIR FLOW METER Click here

    OK

  30. REMOVE DEPOSIT (ELECTRIC EGR CONTROL VALVE ASSEMBLY)


    1. Remove the electric EGR control valve assembly.

    2. Visually check the electric EGR control valve assembly for deposits.

      If there are deposits, clean the electric EGR control valve assembly.

      Tech Tips


      • If the EGR valve is stuck closed, the intake air amount increases and engine vibration may worsen.

      • If the EGR valve does not operate due to clogging or disconnection of the vacuum hose, repair the hose.

      • 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.

      • When cleaning the electric EGR control valve assembly, use a piece of cloth soaked with non-residue solvent. Spraying the solvent directly onto this part or soaking it in solvent may damage it.

    3. Reinstall the electric EGR control valve assembly.


    NEXT

  31. INSPECT ELECTRIC EGR CONTROL VALVE ASSEMBLY


    1. Inspect the electric EGR control valve assembly Click here.


    OK

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

    NG

    REPLACE ELECTRIC EGR CONTROL VALVE ASSEMBLY Click here

  32. REPAIR OR REPLACE AIR INTAKE SYSTEM


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


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  33. REPLACE MASS AIR FLOW METER


    1. Replace the mass air flow meter Click here.

      Tech Tips

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


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  34. REPLACE ELECTRIC EGR CONTROL VALVE ASSEMBLY


    1. Replace the electric EGR control valve assembly Click here.


    NEXT

  35. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    OK

    END

    NG

    CHECK FRONT EXHAUST PIPE ASSEMBLY (CATALYST CONVERTER) Click here

  36. READ VALUE USING INTELLIGENT TESTER (MAF)


    1. Connect the intelligent tester to the DLC3.

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

    3. Enter the following menus: Powertrain / Engine and ECT / Data List / MAF.

    4. Read the value.

      Standard
      Tester Display Condition Specified Condition
      MAF Engine not running Less than 0.3 g/sec

    NG

    REPLACE MASS AIR FLOW METER Click here

    OK

  37. CHECK FRONT EXHAUST PIPE ASSEMBLY (CATALYST CONVERTER)


    1. Remove the front exhaust pipe assembly.

    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 front exhaust pipe assembly.


    NG

    REPLACE FRONT EXHAUST PIPE ASSEMBLY (CATALYST CONVERTER) Click here

    OK

  38. INSPECT TURBOCHARGER SUB-ASSEMBLY


    1. Inspect the turbocharger sub-assembly Click here.


    NG

    REPLACE TURBOCHARGER SUB-ASSEMBLY Click here

    OK

  39. CHECK FOR INTERMITTENT PROBLEMS


    1. Check for intermittent problems Click here.


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  40. REPLACE MASS AIR FLOW METER


    1. Replace the mass air flow meter Click here.

      Tech Tips

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


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  41. REPLACE FRONT EXHAUST PIPE ASSEMBLY (CATALYST CONVERTER)


    1. Replace the front exhaust pipe assembly.


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  42. REPLACE TURBOCHARGER SUB-ASSEMBLY


    1. Replace the turbocharger sub-assembly Click here.


    NEXT

  43. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    NEXT

    END

  44. 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 intelligent tester.

      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

    CHECK SNAPSHOT (MAP AND MAF) Click here

    B

  45. EXPLAIN THE INVESTIGATION RESULT TO CUSTOMER


    1. Vehicle performance is normal.

      There is no problem at this point in time. However, if the problem reoccur, 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.


    NEXT

    END