ECD SYSTEM Engine Knocking or Rattling

DESCRIPTION

Malfunction Condition Main Trouble Area Related Trouble Area

Combustion in diesel engines takes place by means of self-ignition. If the timing of the ignition is delayed, the pressure inside the combustion chamber will increase too fast, which leads to uncontrolled combustion and can be heard as diesel knocking.

If any of the following conditions are met, engine knocking may occur due to the fact that


  • The diesel fuel self-ignition timing takes place too late

  • The engine temperature is low

  • The intake air temperature is low

  • The self-ignition temperature of the diesel fuel is high (e.g., low cetane number)

  • Fuel is injected into a cold combustion chamber (compression temperature is too low)

  • There is inadequate fuel vaporization (air-fuel mixture formation is unsatisfactory)

  • There is pilot injection deterioration due to an injector sticking or contamination

  1. Injector malfunctions


    • Injector sliding malfunction

    • Injector stuck closed

    • Injector stuck open

    • Deposits in injector

    • Injector circuit malfunction

  2. Abnormal common rail pressure


    • Fuel supply pump

    • Fuel pulsation sound

    • Air in fuel

  3. Friction between parts

  4. Compression pressure

  • Fuel injector compensation codes

  • Fuel leakage

  • Intake system leakage

  • Intake system blockage

  • EGR system

  • Throttle valve system

  • Fuel pressure sensor

  • Turbo pressure sensor

  • 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.


  1. Faults and Symptoms of Common Rail Diesel Components


    1. Engine Control

      Mass Air Flow Meter
      Component 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.
      Glow System
      Component 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 Try to measure the resistance of the glow plug

    2. Diesel Injection

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

      Fuel Press, Target Common Rail Pressure, Target Pump SCV Current


      • When in a stable condition such as when idling, the fuel pressure is within +/-10000 kPa of the target fuel 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 starting, but is approx. 25000 kPa at engine start after the engine is warmed up.

      • When Target Pump SCV Current is 1530 mA or more, the suction control valve has a tendency to become stuck.
      Diagnostic Trouble Code Even if Fuel Press is less than Target Common Rail Pressure, a DTC may not be stored.
      Fuel Filter
      Component Fuel filter
      Main fault Blockage
      Symptoms Difficult to start, engine stalling, rough idle, lack of power
      Data List

      Fuel Press, Target Common Rail Pressure


      • When in a stable condition such as when idling, the fuel pressure is within +/-10000 kPa of the target fuel 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 starting, but is approx. 25000 kPa at engine start after the engine is warmed up.
      Diagnostic Trouble Code Even if Fuel Press is less than Target Common Rail Pressure, a DTC may not be stored.
      Fuel Injector
      Component Fuel injector
      Main fault

      Injection hole blockage

      Nozzle needle or valve piston does not move smoothly
      Symptoms Rough idle, lack of power, black smoke, white smoke, knocking
      Data List

      Injection Feedback Val


      • "Injection Feedback Val" more than 2.0 mm3/st: Injector breakdown is causing injection volume deviation, or insufficient compression is causing poor combustion.
      Fuel Pressure Sensor
      Component 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

      Fuel Press, Target Common Rail Pressure


      • Slowly raise the engine speed from idling to 3000 rpm with the vehicle stopped, and check that Fuel Press follows Target Common Rail Pressure. If the fuel pressure sensor malfunctions, the actual fuel pressure may deviate from the target fuel pressure. (However, the value may not deviate even when a malfunction is present).
      Diagnostic Trouble Code When the fuel pressure sensor has a fault, some DTCs may be stored.
      Irregular Fuel
      Component Irregular fuel
      Main fault -
      Symptoms Difficult to start, rough idle (especially when cold)

    3. Diesel EGR

      EGR System
      Component EGR system
      Main fault

      • Does not move smoothly

      • Does not close completely
      Symptoms

      • Rough idle

      • EGR valve stuck closed: A loud turbocharger sound.

      • EGR valve stuck open: Difficult to start (does not stall), black smoke, lack of power (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).
      Data List

      Actual EGR Valve Pos., Target EGR Pos.


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

      • Using EGR valve Active Test, check whether Actual EGR Valve Pos. follows Target EGR 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 turned to ON (engine stopped).

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

    4. Diesel Throttle

      Diesel Throttle System
      Component 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, Target Throttle Position

        0%: Fully open

        100%: Fully closed

      • If there is a malfunction of the throttle actuator, compare the target and actual throttle position values for the troubleshooting.

  2. Data List Related to Engine Knocking and Rattling

    Tech Tips

    The Data List values in the table are the results of checking one vehicle under a specific condition (engine coolant temperature, intake air temperature, atmospheric pressure etc.). Therefore, use these values for reference only.


    1. Engine Control

      Engine Speed
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Engine Speed Idling: 720 to 820 rpm

      • Crankshaft position sensor

      • Crankshaft position sensor circuit

      		 When the crankshaft position sensor is malfunctioning, "Engine Speed" is approximately 0 or varies greatly from the actual engine speed.
      MAP
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      MAP

      • When MAP is low, there will be difficulty starting.

      • With ignition switch ON or during idling, MAP is nearly equal to Atmosphere Pressure (standard atmospheric pressure = 101 kPa).

      When MAP is low, the following conditions are possible:


      • Diesel throttle nearly fully closed.

      • Intake system blocked (turbocharger system also).

      • Exhaust system blocked.

      • When the ignition switch is ON or the vehicle is idling, MAP (intake manifold absolute pressure) and Atmosphere Pressure are approximately equal (standard atmospheric pressure = 101 kPa).

        Above approx. 1500 rpm, the turbo becomes effective, and the pressure becomes higher than atmospheric pressure.

      • Inspect while comparing with "Target Booster Pressure".

      • With the accelerator fully open, if the MAP (intake manifold absolute pressure) is low compared to the target booster pressure by at least 15 kPa for 5 seconds or more, a feeling of insufficient power will occur.

      Results of real-vehicle check:


      • Ignition switch ON: 98 kPa

      • Cranking: 98 kPa

      • Idling (warm up the engine): 99 kPa (2 minutes after starting the vehicle)

      • Running without load (2500 rpm): 109 kPa

      • Running without load (3000 rpm): 131 kPa

      • Running without load (4000 rpm): 163 kPa

      • Running without load (4500 rpm): 173 kPa

      • Driving with the accelerator fully open at 2000 rpm: 183 kPa

      • Driving with the accelerator fully open at 3000 rpm: 217 kPa

      • Driving with the accelerator fully open at 4500 rpm: 205 kPa
      MAF
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      MAF -

      • MAF meter

      • MAF meter circuit

      • Intake system clogging, leaking

      • Exhaust system clogging

      • Turbocharger sub-assembly

      • Leaking or clogging of turbocharger passages

      • EGR valve does not close

      • Based on the MAF, the ECM controls the fuel injection volume, injection timing, EGR, etc.

      • If the value is always approximately 0 gm/sec.:


        • Mass air flow meter power source circuit is open.

        • VG circuit is open or shorted.

      • If the value is always 200 gm/sec. or more:


        • EVG circuit is open.

      Results of real-vehicle check:


      • Ignition switch ON: 0 gm/sec.

      • Cranking (295 rpm): 2.72 gm/sec.

      • Idling (warm up the engine): 5.0 gm/sec. (2 minutes after starting the vehicle and "Actual EGR Valve Pos." = 56%)

      • Idling (warm up the engine): 8.5 gm/sec. (2 minutes after starting the vehicle and "Actual EGR Valve Pos." = 0.3%)

      • Running without load (2500 rpm): 21.2 gm/sec. (at "Actual EGR Valve Pos." = 56%)

      • Running without load (4500 rpm): 69.8 gm/sec.

      • Driving with the accelerator fully open at 2000 rpm: 43.94 gm/sec.

      • Driving with the accelerator fully open at 3000 rpm: 72.47 gm/sec.

      • Driving with the accelerator fully open at 4500 rpm: 87.8 gm/sec.

      Tech Tips


      • The maximum fuel injection volume is controlled according to the output from the mass air flow meter.

      • If the time of engine idling is long (approximately 20 minutes or more), EGR will be cut off. At this time, if the vehicle is driven in 5th gear at 70 km/h for 10 minutes, EGR resumes.
      Intake Air
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Intake Air - Intake air temperature sensor.

      • After a long soak, the engine coolant temperature, intake air temperature and ambient air temperature are approximately equal.

      • If the value is -40°C (-40°F) or 140°C (284°F), the sensor circuit is open or shorted.
      Coolant Temp
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Coolant Temp

      • Engine coolant temperature is approximately equal to intake air temperature after a long soak. After warm-up: Engine coolant temperature is 75°C (167°F) or more.

      • In cases when the engine coolant temperature output is obviously higher than the actual engine coolant temperature, when it is cold, there will be difficulty starting due to problems with glow plugs or insufficient fuel injection.

      • In cases when the engine coolant temperature sensor output is obviously lower than the actual engine coolant temperature, when it is warm, there will be difficulty starting (black smoke will also occur) due to an excess of injected fuel.

      		 Engine coolant temperature sensor

      • If the value is -30°C (-22°F) or 120°C (248°F), the sensor circuit is open or shorted.

      • After a long soak, the Coolant Temp, Intake Air and ambient air temperature are approximately equal.
      Engine Speed of Cyl #1 (to #4)
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Engine Speed of Cyl #1 (to #4)

      When cranking, the engine speed of each cylinder is the same under normal conditions. When a cylinder is approximately 100 rpm higher than the other cylinders, it is conceivable that the compression of that cylinder is being lost.

      Tech Tips

      Usually the tester displays the value of when the engine is started.

      		 -

      • The engine is cranked for approximately 10 seconds, then the speed of each cylinder is measured (compression test).

      • Indicates the speed of each cylinder when cranking. Example - Normal: Engine speed of all cylinders is approximately equal. When No. 1 cylinder compression is extremely low, "Engine speed of Cyl #1" is approximately 300 rpm, and "Engine speed of Cyl #2 to #4" is approximately 200 rpm.

    2. Diesel Injection

      Target Common Rail Pressure
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Target Common Rail Pressure - -

      • Inspect the (actual) fuel pressure, comparing it against the common rail target value.

      • Considered normal when the actual fuel pressure is within +/-10000 kPa of the target fuel pressure under stable conditions.

      Results of real-vehicle check:


      • Ignition switch ON: 25000 kPa

      • Cranking: 21470 kPa

      • Idling (warm up the engine): 25000 kPa (2 minutes after starting the vehicle)

      • Running without load (2500 rpm): 35590 kPa

      • Running without load (3500 rpm): 80200 kPa

      • Running without load (4500 rpm): 68200 kPa

      • Driving with the accelerator fully open at 2000 rpm: 114330 kPa

      • Driving with the accelerator fully open at 3000 rpm: 156460 kPa

      • Driving with the accelerator fully open at 4500 rpm: 160000 kPa
      Fuel Press
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Fuel Press

      • Idling: 19900 to 37000 kPa 4000 rpm: 50700 to 73000 kPa Fuel Press = Target Common Rail Pressure +/-10000 kPa at stable condition

      • During cranking, if Fuel Press is lower than 25000 kPa, there may be difficulty starting (take care as there is a response lag when the pressure rises).

      • When Fuel Press is lower than 25000 kPa, rough idling will occur.

      • If there is a fault with the fuel supply pump (lack of discharge quantity) or pressure control valve (will not fully close), the fuel pressure will drop. Also, a blocked fuel filter, leakage from fuel pipes, and lack of fuel will also make the fuel pressure drop.

      • If air mixes with the fuel, the fuel pressure will shift away from the target fuel pressure.

      • When there is a fault with the fuel supply pump, there is a possibility of lack of power, engine stall, rough idle and difficulty starting.

      • Fuel pressure is the actual common rail fuel pressure.

      • Inspect by comparing the fuel pressure with the target fuel pressure.

      • When in a stable condition such as when idling, the fuel pressure is within +/-10000 kPa of the target fuel pressure.

      • The ECM uses fuel pressure for feedback control of the target fuel pressure via the supply pump. The injection amount is determined based on the injection timing and fuel pressure.

      Results of real-vehicle check:


      • Ignition switch ON: 140 kPa

      • Cranking: 21920 kPa

      • Idling (warm up the engine): 25430 kPa (2 minutes after starting the vehicle)

      • Running without load (2500 rpm): 35550 kPa

      • Running without load (4500 rpm): 68990 kPa

      • Driving with the accelerator fully open at 2000 rpm: 114950 kPa

      • Driving with the accelerator fully open at 3000 rpm: 154320 kPa

      • Driving with the accelerator fully open at 4500 rpm: 160280 kPa
      Target Pump SCV Current
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Target Pump SCV Current 1530 mA or less

      • Suction control valve malfunction

      • Clogged fuel filter

      • ECU-calculated value for the suction control valve actuation target current.


      • Value is large when a high fuel pressure is desired.

      • Value becomes stuck at 1800 mA or more or operation is poor (poor movement due to deposits, etc.).

      • When this deviates from the standard value, it indicates that for some reason, even though the pump is running hard, the actual fuel pressure is inconsistent with the target fuel pressure.

      Results of real-vehicle check:


      • Cranking: 1052 mA

      • Idling: 1167 mA

      • Running without load (2500 rpm): 1300 mA

      • Running without load (4500 rpm): 1188 mA

      • Driving with the accelerator fully open at 2000 rpm: 1102 mA

      • Driving with the accelerator fully open at 3000 rpm: 934 mA

      • Driving with the accelerator fully open at 4500 rpm: 920 mA
      Injection Feedback Val #1 (to #4)
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Injection Feedback Val #1 (to #4)

      • When idling after the engine is warmed up, the fuel quantity of each fuel injector is corrected to make each cylinder engine speed equal.

      • Cylinders more than 2 mm3/st may have a fault.

      Tech Tips

      Read the value after one minute of idling after warm up (engine coolant temperature above 75°C (167°F)). This value is only calculated when idling.

      • Injector clogging

      • Injector deterioration

      • Decrease in cylinder compression

      • Injector compensation code is incorrectly set (forgot to input code after replacement or made mistake during setting of code after replacing ECM with one from another vehicle)

      • With fuel injector faults, other than difficulty starting, there is a possibility of rough idling, lack of power, black smoke, white smoke and knocking.

      • When idling after warm up, the injection amount for each cylinder is corrected to optimize the difference between the engine speed of each cylinder. Example: For cylinders that are slowing the engine speed compared to other cylinders, the injection volume is increased.

      • "Injection Feedback Val" more than 2.0 mm3/st: Injector breakdown is causing injection volume deviation, or insufficient compression is causing poor combustion.
      Injection Volume
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Injection Volume - - If injectors are clogged, fuel quality is poor, the fuel filter is clogged, or engine friction increases, then "Injection Volume" will increase.

      Results of real-vehicle check:


      • Cranking: 19.58 mm3/st

      • Idling (warm up the engine): 4.19 mm3/st (at "Actual EGR Valve Pos." = 0.3%)

      • Idling (warm up the engine): 4.58 mm3/st (at "Actual EGR Valve Pos." = 56%)

      • Running without load (2500 rpm): 4.68 mm3/st

      • Running without load (4500 rpm): 8.28 mm3/st

      • Driving in 3rd gear 60 km/h (37 mph): 9.39 mm3/st

      • Driving in 3rd gear 60 km/h (37 mph) during PM regeneration: 26.28 mm3/st

      • Driving with the accelerator fully open at 2000 rpm: 36.48 mm3/st

      • Driving with the accelerator fully open at 3000 rpm: 46.97 mm3/st

      • Driving with the accelerator fully open at 4500 rpm: 37.89 mm3/st
      Pilot 1 Injection Period
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Pilot 1 Injection Period Idling: 140 to 340 μs - -

      Results of real-vehicle check:


      • Cranking: 189 μs

      • Idling (warm up the engine): 228 μs

      • Running without load (2500 rpm): 231 μs

      • Running without load (3500 rpm): 363 μs

      • Driving with the accelerator fully open at 2000 rpm: 169 μs

      • Driving with the accelerator fully open at 3000 rpm: 167 μs
      Main Injection Period
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Main Injection Period Idling: 232 to 432 μs - -

      Results of real-vehicle check:


      • Cranking: 639 μs

      • Idling (warm up the engine): 307 μs (2 minutes after starting the vehicle)

      • Running without load (2500 rpm): 515 μs

      • Driving in 3rd gear 60 km/h (37 mph): 326 μs

      • Driving in 3rd gear 60 km/h (37 mph) during PM regeneration: 235 μs

      • Driving with the accelerator fully open at 2000 rpm: 553 μs

      • Driving with the accelerator fully open at 3000 rpm: 546 μs

      • Driving with the accelerator fully open at 4500 rpm: 439 μs

    3. Diesel Throttle

      Actual Throttle Position
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Actual Throttle Position

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

      • With the diesel throttle stuck almost fully closed, there is a possibility of rough idling, engine stall, black smoke, difficulty starting and lack of power.

      		 Diesel throttle body

      Closing percentage of the throttle valve.


      • Fully closed: 100%

      • Fully open: 0%

      If there is a malfunction of the throttle actuator, compare the target and actual throttle position values for the troubleshooting.

      Results of real-vehicle check:


      • Ignition switch ON: -1%

      • Cranking: -1%

      • Idling (warm up the engine): -1%

      • Running without load (2500 rpm): 0%

      • Running without load (4500 rpm): 0%

      • Driving in 3rd gear 60 km/h (37 mph): -1%

      • Driving in 3rd gear 60 km/h (37 mph) during PM regeneration: 78%

      • Driving with the accelerator fully open at 2000 rpm: 0%

      • Driving with the accelerator fully open at 4500 rpm: 0%

      • Soon after engine running to ignition switch off: 0% → 99% → 0%

    4. Diesel EGR

      Target EGR Position
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Target EGR Position - -

      • Fully open: 100%

      • Fully closed: 0%

      • Used for comparison to "Actual EGR Valve Pos".

      Tech Tips

      If the time of engine idling is long (approximately 20 minutes or more), EGR will be cut off. At this time, if the vehicle is driven in 5th gear at 70 km/h for 10 minutes, EGR resumes.

      Results of real-vehicle check:


      • Ignition switch ON: 0%

      • Cranking: 0%

      • Idling with EGR off (warm up the engine): 0.3%

      • Idling with EGR on (warm up the engine): 56%

      • Running without load (2500 rpm): 57%

      • Running without load (4500 rpm): 0%

      • Driving with the accelerator fully open at 2000 rpm: 0%

      • Driving with the accelerator fully open at 3000 rpm: 0%

      • Driving with the accelerator fully open at 4500 rpm: 0%
      Actual EGR Valve Pos.
      Data List Judgment of Data List Values Faulty Component Diagnosis Note
      Actual EGR Valve Pos.

      • Generally Actual EGR Valve Pos. = Target EGR Position (Fully closed = 0%, Fully open = 100%)

      • The EGR valve Active Test can be used to check whether the Actual EGR Valve Pos. = Target EGR Position

      		 EGR valve assembly

      • Fully open: 100%

      • Fully closed: 0%

      • Inspect while comparing to "Target EGR Position".

      • Check the valve movement via the Active Test.

      • Sometimes the malfunction only occurs around a certain temperature, so refer to the engine coolant temperature and outside temperature at the time the malfunction occurred.

      Tech Tips

      If the time of engine idling is long (approximately 20 minutes or more), EGR will be cut off. At this time, if the vehicle is driven in 5th gear at 70 km/h for 10 minutes, EGR resumes.

      Results of real-vehicle check:


      • Ignition switch ON: 0%

      • Cranking: 0%

      • Idling with EGR off (warm up the engine): 0%

      • Idling with EGR on (warm up the engine): 56%

      • Running without load (2500 rpm): 56%

      • Running without load (4500 rpm): 0.3%

      • Driving in 3rd gear 60 km/h (37 mph): 57%

      • Driving in 3rd gear 60 km/h (37 mph) during PM regeneration: 0.3%

      • Driving with the accelerator fully open at 2000 rpm: 0.3%

      • Driving with the accelerator fully open at 3000 rpm: 0.3%

      • Driving with the accelerator fully open at 4500 rpm: 0%

WIRING DIAGRAM

Refer to DTC P1228 Click here.

INSPECTION PROCEDURE

Note

When replacing the ECM and/or fuel injector, the ECM needs Registration and Initialization Click here.

Tech Tips


  • This troubleshooting procedure checks for knocking and rattling.

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


  1. Explanation of Symptom

    Engine knocking or rattling

    Combustion in diesel engines takes place by means of self-ignition. If the timing of the ignition is delayed, the pressure inside the combustion chamber will increase too fast, which leads to uncontrolled combustion and can be heard as diesel knocking.

    If one of the following conditions are met, engine knocking may occur due to the fact that


    • The diesel fuel self ignition timing takes place too late

    • The engine temperature is low

    • The intake air temperature is low

    • The self-ignition temperature of the diesel fuel is high (e.g., low cetane number)

    • Fuel is injected into a cold combustion chamber (compression temperature is too low)

    • There is inadequate fuel vaporization (air-fuel mixture formation is unsatisfactory)

    • There is pilot injection deterioration due to an injector sticking or contamination

PROCEDURE


  1. CHECK FOR KNOCKING SOUND


    1. Open the hood and check for knocking.

      Result
      Result Proceed to
      Knocking A
      No knocking B

    B

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

  2. CHECK HARNESS AND CONNECTOR (IN ENGINE ROOM)


    1. Check the harness and connector connections of common rail system components.

      OK
      The wire harnesses and connectors are connected securely.

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK INTAKE SYSTEM (PROCEDURE 3)


    1. Check the intake system (turbocharger, MAP sensor, EGR valve, etc.).

      OK
      All hoses are connected securely and there are no leaks or blockage in the air induction system.

    NG

    REPAIR OR REPLACE INTAKE SYSTEM

    OK

  4. READ OUTPUT DTCS (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 DTCs.

      Result
      Result Proceed to
      No output A
      Engine related DTCs B

    B

    GO TO DTC CHART Click here

    A

  5. READ VALUE USING INTELLIGENT TESTER (MAP AND ATMOSPHERE 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 7 kPa.

      Tech Tips


      • If MAP and Atmosphere Pressure have the same value, both are normal. If there is a difference of 7 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 altitude, pressure drops by 1 kPa. Varies by weather (high atmospheric pressure, low atmospheric pressure)

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

    B

    REPLACE TURBO PRESSURE SENSOR Click here

    C

    REPLACE ECM Click here

    A

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


    1. Connect the intelligent tester to the DLC3.

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

    3. A011A55E01

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

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

      Tech Tips

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

    5. Maintain the engine speed of 3500 rpm, and then press the "Start" button.

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

      A0117GYE02

      Tech Tips


      • The EPS, ABS and SRS warning lights may blink when the engine speed exceeds 3500 rpm during this test.

      • To ensure accurate measurements, perform the Active Test with measurements 5 times or more.

      Standard
      The difference between the target fuel pressure and the actual fuel pressure is less than 15000 kPa when the target fuel pressure reaches the maximum value approximately 2 seconds after the Active Test starts.

    7. Read the value of Target Pump SCV Current in the Data List when the "Test the Fuel Leak" Active Test is performed.

      Standard current
      Target Pump SCV Current is less than 1530 mA.

      Tech Tips

      If the value of Target Pump SCV Current stored in the snapshot is higher than the standard, the intermittent suction control valve is probably stuck.

      Result
      Result Proceed to
      Both results are within standard A

      Fuel pressure exceeds "Target Common Rail Pressure + 15000 kPa"

      and/or

      Target Pump SCV Current value is out of standard range

      		 B
      Fuel pressure does not reach "Target Common Rail Pressure - 15000 kPa" C

    B

    CHECK HARNESS AND CONNECTOR (SUCTION CONTROL VALVE - ECM) Click here

    C

    BLEED AIR FROM FUEL SYSTEM Click here

    A

  7. CHECK INJECTOR COMPENSATION CODE


    1. Check the injector compensation codes Click here.

      OK
      Compensation codes of the installed injectors are the same as the compensation codes registered in the ECM.

    NG

    PERFORM REGISTRATION AND INITIALIZATION Click here

    OK

  8. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Check whether the malfunction has been successfully repaired.

      OK
      Malfunction has been repaired successfully.

    NG

    READ VALUE USING INTELLIGENT TESTER (CONTROL THE EGR STEP POSITION) Click here

    OK

    END

  9. READ VALUE USING INTELLIGENT TESTER (CONTROL THE EGR STEP POSITION)


    1. Turn the ignition switch to ON.

    2. Turn the ignition switch off and wait for 30 seconds or more.

    3. Connect the intelligent tester to the DLC3.

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

    5. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position / Data List / Actual EGR Valve Pos.

    6. When changing the Active Test value from 0 to 100%, check that Actual EGR Valve Pos. smoothly changes to the set opening angle.

      OK
      Value smoothly changes to the set opening angle.

      Tech Tips

      Under normal conditions, Actual EGR Valve Pos. is indicated as follows.

      EGR Valve Condition Actual EGR Valve Pos.
      Fully closed 0%
      Fully open About 100%

    NG

    REPLACE ELECTRIC EGR VALVE ASSEMBLY Click here

    OK

  10. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (DIESEL THROTTLE TARGET ANGLE)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Active Test / Diesel Throttle Target Angle.

    4. When continuously changing the Active Test value to 0, 30, 60, 90, 60, 30 and 0%, check that Actual Throttle Position smoothly changes to the set opening angle.

      OK
      Value smoothly changes to the set opening angle.

    NG

    REPLACE DIESEL THROTTLE BODY ASSEMBLY Click here

    OK

  11. CHECK THE TEMPERATURE WHEN KNOCKING OCCURS


    1. Check the temperature when knocking trouble occurs.

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

    B

    READ VALUE USING INTELLIGENT TESTER (MAP AND MAF) Click here

    A

  12. INSPECT ENGINE COOLANT TEMPERATURE SENSOR


    1. After warming up the engine, the engine coolant temperature should be 60°C (140°F) or more. After leaving the vehicle overnight, the engine coolant temperature should be nearly equal to the intake air temperature.

      OK
      The engine coolant temperature is nearly equal to the intake air temperature.

      Tech Tips

      If the engine coolant temperature sensor output is less than the actual engine coolant temperature, engine knocking may occur.


    NG

    REPLACE ENGINE COOLANT TEMPERATURE SENSOR Click here

    OK

  13. CHECK PRE-HEATING CONTROL CIRCUIT


    1. Check the pre-heating control circuit Click here.


    NG

    REPAIR OR REPLACE MALFUNCTIONING PARTS

    OK

  14. READ VALUE USING INTELLIGENT TESTER (INJECTOR FEEDBACK VAL #1 TO #4)

    Tech Tips


    • Read the values of Injector Feedback Val. #1 to #4 when the engine is cold.

    • If the engine coolant temperature is more than 40°C (104°F), leave the vehicle until the engine coolant reaches almost the same temperature as the atmospheric temperature.


    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 / Injector Feedback Val. #1 to #4.

    4. Start the engine.

    5. Read the values during engine idling when the engine is cold, and write them down.

      Standard
      Tester Display Condition Specified Condition

      Injector Feedback Val. #1

      Injector Feedback Val. #2

      Injector Feedback Val. #3

      Injector Feedback Val. #4

      		 Idling with cold engine

      Between -2.0 and 2.0 mm3/st

      Tech Tips

      If any Injector Feedback Val. is out of the specified range, replace all of the fuel injectors together.


    NG

    REPLACE INJECTOR ASSEMBLY Click here

    OK

  15. READ VALUE USING INTELLIGENT TESTER (MAP AND MAF)


    1. Connect the intelligent tester to the DLC3.

    2. Start the engine, warm it up, and then turn the tester on.

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

      Standard
      Item Engine Speed*1 Standard Range Description
      MAP*2 Ignition switch ON (engine stopped) Same as atmospheric pressure Intake manifold internal pressure detected by manifold absolute pressure sensor
      Idling 90 to 102 kPa (675 to 765 mmHg, 26.58 to 30.12 in.Hg)
      3000 rpm (no engine load) 100 to 150 kPa (750 to 1125 mmHg, 29.53 to 44.29 in.Hg)
      3500 rpm (driving with full throttle acceleration) Min. 180 kPa (1350 mmHg, 53.15 in.Hg)
      MAF*2, *3 Ignition switch ON (engine stopped) Less than 0.5 gm/sec Intake air volume detected by mass air flow meter
      Idling 3.5 to 12 gm/sec
      2000 rpm (no engine load) 10 to 40 gm/sec
      3500 rpm (driving with full throttle acceleration) Min. 67 gm/sec
      Result
      Item Result Proceed to
      MAP and MAF Within standard range A
      MAP and MAF Outside standard range B
      Only MAP Outside standard range C
      Only MAF Outside standard range D

      Tech Tips

      *1: The A/C switch and all accessory switches should be off with a fully warm engine.

      *2: This value is indicated when the ambient temperature is 25°C (77°F), the atmospheric pressure is 101 kPa (758 mmHg, 29.83 in.Hg), and a stable boost pressure is maintained for approximately 10 seconds.

      *3: When the mass air flow meter malfunctions, the MAF output may deviate from the standard (referential) range when the engine idles and is accelerated from 3000 to 4000 rpm with full throttle acceleration.


    B

    CHECK INTAKE SYSTEM (PROCEDURE 3)

    C

    GO TO DTC P0236 (RELATED TO TURBO PRESSURE SENSOR) Click here

    D

    GO TO DTC P0102 AND P0103 (RELATED TO MASS AIR FLOW METER) Click here

    A

  16. INSPECT ELECTRIC EGR VALVE ASSEMBLY


    1. Remove the electric EGR valve assembly Click here.

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

      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.

    3. Hold the electric EGR control valve up to a light, and then from the side indicated by the arrow in the illustration, visually check that there is no clearance between the valve and body.

      A01187PE01
      OK
      No light passes through (there is no clearance between the valve and body).

      If light passes through (there is a clearance between the valve and body), replace the electric EGR control valve assembly.

      Tech Tips

      Light passes through part A shown in the illustration even if the valve is completely closed, this is not a problem.

    4. Reinstall the electric EGR valve assembly Click here.


    NG

    REPLACE ELECTRIC EGR VALVE ASSEMBLY Click here

    OK

  17. BASIC INSPECTION


    1. Check the fuel quality.

    2. Check the fuel line for air.

    3. Check the fuel system for blockages.

    4. Check the air filter.

    5. Check the engine oil.

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

    7. Check the vacuum pump.


    NG

    REPAIR OR REPLACE MALFUNCTIONING PARTS

    OK

  18. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Check whether the malfunction has been successfully repaired.

      OK
      Malfunction has been repaired successfully.

    NG

    READ VALUE USING INTELLIGENT TESTER (INJECTION VOLUME AND INJECTOR) Click here

    OK

    END

  19. READ VALUE USING INTELLIGENT TESTER (INJECTION VOLUME AND INJECTOR)


    1. Connect the intelligent tester to the DLC3.

    2. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

    3. Allow the engine to idle for 1 minute or more.

      Tech Tips

      The A/C switch and all accessory switches should be off with a fully warm engine.

    4. Turn the tester on.

    5. Enter the following menus: Powertrain / Engine and ECT / Data List / Injection Volume and Injector Feedback Val. #1 to #4.

    6. Read the values during engine idling.

      Tech Tips

      When reading the values of Data List, confirm that PM regeneration is not activating (value of "After Injection Period" is 0) by entering the following menus: Powertrain / Engine and ECT / Data List / After Injection Period.

      If PM regeneration is activating (value of "After Injection Period" is not 0), drive the vehicle until the PM regeneration is complete (value of "After Injection Period" becomes 0).

      Standard
      Tester Display Condition Specified Condition
      Injection Volume Idling

      8 mm3/st or less

      Injector Feedback Val. #1

      Injector Feedback Val. #2

      Injector Feedback Val. #3

      Injector Feedback Val. #4

      		 Idling

      Between -2.0 and 2.0 mm3/st

      Tech Tips


      • Cylinders that have a compensation value which is more than the value specified above are considered to be faulty. Use the following steps to inspect and repair the cylinder.

      • If the value of Injection Volume is more than 8 mm3/st and the value of all of the Injector Feedback Val. #1 to #4 is within the threshold, replace the fuel injectors for all cylinders.

        In this case, there is a possibility that too much recirculated exhaust gas enters into the engine. Therefore, you should compare the Target EGR Position with the Actual EGR Valve Pos. by entering the following menus using the intelligent tester: Powertrain / Engine and ECT / Data List / Target EGR Position and Actual EGR Valve Pos.

        If the difference between Target EGR Position and Actual EGR Valve Pos. exceeds +/-10%, the EGR system may have a malfunction.


    NG

    REPLACE INJECTOR ASSEMBLY Click here

    OK

    END

  20. BLEED AIR FROM FUEL SYSTEM


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


    NEXT

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


    1. Connect the intelligent tester to the DLC3.

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

    3. A011A55E01

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

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

      Tech Tips

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

    5. Maintain the engine speed of 3500 rpm, and then press the "Start" button.

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

      A0117GYE02

      Tech Tips


      • The EPS, ABS and SRS warning lights may blink when the engine speed exceeds 3500 rpm during this test.

      • To ensure accurate measurements, perform the Active Test with measurements 5 times or more.

      Standard
      The difference between the target fuel pressure and the actual fuel pressure is less than 15000 kPa when the target fuel pressure reaches the maximum value approximately 2 seconds after the Active Test starts.

    NG

    CHECK HARNESS AND CONNECTOR (SUCTION CONTROL VALVE - ECM) Click here

    OK

  22. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    NEXT

    END

  23. CHECK HARNESS AND CONNECTOR (SUCTION CONTROL VALVE - ECM)


    1. Disconnect the suction control valve connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      B42-2 - B9-12 (PCV) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      B42-2 or B9-12 (PCV) - Body ground Always 10 kΩ or higher

    4. Reconnect the suction control valve connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  24. CONFIRM IF FUEL BEING SUPPLIED TO FUEL SUPPLY PUMP


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

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

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

      Tech Tips


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

      • Check that the fuel filter is not clogged.

      • Check for fuel freezing in the fuel line.

      • Check for clogging or leaks in the fuel pipe and hose between the fuel tank and fuel supply pump.


    NG

    REPAIR OR REPLACE FUEL FILTER OR CLOGGED FUEL PIPE (INCLUDING FUEL FREEZING, FUEL TANK - FUEL SUPPLY PUMP)

    OK

  25. REPLACE FUEL SUPPLY PUMP


    1. Replace the fuel supply pump Click here.


    NEXT

  26. BLEED AIR FROM FUEL SYSTEM


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


    NEXT

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


    1. Connect the intelligent tester to the DLC3.

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

    3. A011A55E01

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

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

      Tech Tips

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

    5. Maintain the engine speed of 3500 rpm, and then press the "Start" button.

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

      A0117GYE02

      Tech Tips


      • The EPS, ABS and SRS warning lights may blink when the engine speed exceeds 3500 rpm during this test.

      • To ensure accurate measurements, perform the Active Test with measurements 5 times or more.

      Standard
      The difference between the target fuel pressure and the actual fuel pressure is less than 15000 kPa when the target fuel pressure reaches the maximum value approximately 2 seconds after the Active Test starts.

    OK

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

    NG

    REPLACE COMMON RAIL ASSEMBLY Click here

  28. REPLACE COMMON RAIL ASSEMBLY


    1. Replace the common rail assembly Click here.


    NEXT

  29. BLEED AIR FROM FUEL SYSTEM


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


    NEXT

  30. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    NEXT

    END

  31. REPLACE INJECTOR ASSEMBLY


    1. Replace the injector assembly Click here.


    NEXT

  32. PERFORM REGISTRATION AND INITIALIZATION


    1. Register the injector compensation codes Click here.

    2. Perform Pilot Quantity Learning Values Reset Click here.


    NEXT

  33. BLEED AIR FROM FUEL SYSTEM


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


    NEXT

  34. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    NEXT

    END

  35. PERFORM REGISTRATION AND INITIALIZATION


    1. Register the injector compensation codes Click here.

    2. Perform Pilot Quantity Learning Values Reset Click here.


    NEXT

  36. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    NEXT

    END