ECD SYSTEM, Diagnostic DTC:P0093

DTC Code DTC Name
P0093 Fuel System Leak Detected - Large Leak

DESCRIPTION

The fuel pressure sensor mounted on the common rail assembly converts the fuel pressure inside the common rail assembly into an electrical signal and outputs the signal to the ECM. The ECM controls the fuel supply pump assembly in order to maintain the fuel pressure inside the common rail assembly at a target pressure calculated by the ECM. Refer to System Description Click here.

Tech Tips


  • If the drop in the internal fuel pressure is large when injecting fuel, the ECM interprets this as a fault and stores P0093.

  • If P0093 is present, refer to "Diagnostic Trouble Code (DTC) Table for Common Rail System" Click here.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory
P0093 Fuel System Leak Detected - Large Leak

Fuel pressure drop before and after the fuel injection is larger than the threshold a certain number of times (0.2 seconds or more).

(1 trip detection logic)

  • Fuel line between fuel supply pump assembly and common rail assembly

  • Fuel line between common rail assembly and each injector assembly

  • Common rail assembly

  • Injector assembly

  • Pressure discharge valve (common rail assembly)

  • Fuel pressure sensor (common rail assembly)

  • Crankshaft position sensor

  • Fuel filter element assembly

  • Open or short in injector assembly circuit

  • ECM

 Comes on DTC stored
Related Data List
DTC No. Data List
P0093

  • Common Rail Pressure

  • Target Common Rail Pressure

Tech Tips

When DTC P0093 is set, check the internal fuel pressure of the common rail by entering the following menus on the GTS: Powertrain / Engine and ECT / Data List / Common Rail Pressure.

Reference
Engine Speed Common Rail Pressure
Idling Approximately 25000 to 45000 kPa
3000 rpm (No engine load) Approximately 60000 to 95000 kPa

CONFIRMATION DRIVING PATTERN

DTC No. DTC Detection Drive Pattern
P0093

After idling for 60 seconds, run engine at 2500 rpm for 30 seconds.

Fully depress the accelerator pedal for 5 seconds, and then release it. (*A)

Rev the engine to 3000 rpm and fully release the accelerator pedal immediately after the engine reaches 3000 rpm. (*B)

Repeat procedures (*A) and (*B) 5 times.

MONITOR DESCRIPTION

This DTC indicates that fuel leaks exist in high pressure areas in the common rail system. The ECM constantly monitors the internal fuel pressure of the common rail after the engine is started. The ECM stores this DTC if the drop in the internal fuel pressure is large when injecting fuel.

In the common rail system, high-pressure fuel is always supplied to the high-pressure areas including the fuel supply pump assembly, common rail assembly, injector assemblies and piping.

The ECM adjusts the timing of when the pre-stroke control valve is closed to obtain the target internal fuel pressure.

If this DTC is stored, the ECM enters fail-safe mode. In fail-safe mode, fuel supply pump assembly operation is limited. The ECM continues operating in fail-safe mode until the ignition switch is turned off.

CAUTION / NOTICE / HINT

Note


  • Soon after starting the engine, visually check for fuel leaks in the fuel line.

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

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

Tech Tips

Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.

PROCEDURE


  1. CHECK FOR FUEL LEAKS (IN HIGH-PRESSURE AREAS)


    1. Before starting the engine, visually check for fuel leaks from the fuel supply pump assembly, injector assembly, common rail assembly, and the fuel pipes in high-pressure areas.

      OK
      No fuel leaks in high-pressure areas.
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR FUEL LEAK POINT

    OK

  2. CHECK FOR ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0093) AND RECORD STORED DTC AND FREEZE FRAME DATA (PROCEDURE 2)


    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 and ECT / Trouble Codes.

    4. Read the DTCs and freeze frame data.


      Powertrain > Engine and ECT > Trouble Codes
      Result
      Result Proceed to
      P0093 and "P0190, P0192 and/or P0193" are output C
      P0093 and "P0335, P0337, P0338 and/or P0339" are output B
      Except above A

    B

    GO TO DTC CHART (CRANKSHAFT POSITION SENSOR CIRCUIT) Click here

    C

    GO TO FUEL RAIL PRESSURE SENSOR CIRCUIT Click here

    A

  3. CHECK FUEL RECEIVER GAUGE (AMOUNT OF FUEL)


    1. Check if the fuel level is low.

      Result
      Result Proceed to
      The indicator (fuel warning light) is illuminated A
      The indicator (fuel warning light) is not illuminated B

    B

    GO TO STEP 6 Click here

    A

  4. ADD FLUID


    1. Add fuel.

      Result
      Proceed to
      NEXT

    NEXT

  5. CHECK WHETHER DTC OUTPUT RECURS (DTC P0093)


    1. B0024CA

      Using the hand pump mounted on the fuel filter cap, bleed the air from the fuel system. Continue pumping until the pump resistance increases.

      Note


      • Hand pump pumping speed: Max. 2 strokes/sec.

      • The hand pump must be pushed with a full stroke during pumping.

      • When the fuel pressure at the supply pump inlet port reaches a saturated pressure, the hand pump resistance increases.

      • If pumping is interrupted during the air bleeding process, fuel in the fuel line may return to the fuel tank. Continue pumping until the hand pump resistance increases.

      • If the hand pump resistance does not increase despite consecutively pumping 200 times or more, there may be a fuel leak between the fuel tank and fuel filter element sub-assembly, the hand pump may be malfunctioning, or the vehicle may have run out of fuel.

      • If a large amount of air remains inside the fuel system, the common rail pressure does not rise to the pressure range necessary for normal use, and the engine cannot be started.

    2. Start the engine.

      Note


      • If a large amount of air remains inside the fuel system, the starter may need to be cranked for 10 seconds or more to start the engine.

      • Do not crank the engine continuously for more than 20 seconds. The battery may be discharged.

      • Use a fully-charged battery.


      1. When the engine can be started, proceed to the next step.

      2. If the engine cannot be started, bleed the air again using the hand pump until the hand pump resistance increases. Then start the engine.

    3. Turn the ignition switch off.

    4. Connect the GTS to the DLC3.

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

    6. Clear the DTCs.


      Powertrain > Engine and ECT > Clear DTCs

    7. Start the engine. (*A)

    8. Enter the following menus: Powertrain / Engine and ECT / Active Test / Test the Fuel Leak. (*B)

    9. Perform the following test 5 times with on/off intervals of 10 seconds: Active Test / Test the Fuel Leak. (*C)


      Powertrain > Engine and ECT > Active Test
      Tester Display
      Test the Fuel Leak

    10. Allow the engine to idle for 3 minutes or more after performing the Active Test for the fifth time. (*D)

      B002704E03

    11. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    12. Read Current DTCs.


      Powertrain > Engine and ECT > Trouble Codes

      1. When no DTCs are output, the air bleeding is completed.

      2. If any DTCs are output, proceed to the next step.

    13. Repeat steps (*A) to (*D).

    14. Clear the DTCs.


      Powertrain > Engine and ECT > Clear DTCs

    15. Start the engine and warm it up.

    16. Confirm that the shift lever is in neutral and securely apply the parking brake.

    17. Fully depress the accelerator pedal for 5 seconds, and then release it. (*E)

    18. Rev the engine to 3000 rpm and fully release the accelerator pedal immediately after the engine reaches 3000 rpm. (*F)

    19. Repeat procedures (*E) and (*F) 5 times.

      B0025MJE08

    20. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    21. Read Current DTCs.


      Powertrain > Engine and ECT > Trouble Codes
      Result
      Result Proceed to
      DTC is output A
      No DTC is output B

    B

    DTC CAUSED BY RUNNING OUT OF FUEL

    A

  6. CHECK FREEZE FRAME DATA (INJECTION FEEDBACK VAL #1 TO #4)


    1. Read the value of Injection Feedback Val #1 to #4 in the freeze frame data recorded in Procedure 2.

      Result
      Result Proceed to

      Injection Feedback Val for at least one cylinder is 5 mm3/st in at least 1 set of freeze frame data

      		 B
      Except above A

      Tech Tips

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


    B

    GO TO STEP 10 Click here

    A

  7. READ VALUE USING GTS (COMMON RAIL PRESSURE)


    1. Connect the GTS to the DLC3.

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

    3. Clear the DTCs.


      Powertrain > Engine and ECT > Clear DTCs

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / Common Rail Pressure.


      Powertrain > Engine and ECT > Data List
      Tester Display
      Common Rail Pressure

    5. Start the engine.

    6. Read the value of Common Rail Pressure while cranking and idling the engine.

      Result
      Result Proceed to
      The engine cannot be started or the engine can be started but Common Rail Pressure is below 20000 kPa 2 seconds after the starter signal changes from OFF to ON B
      Except above A

    B

    GO TO STEP 14 Click here

    A

  8. READ VALUE USING GTS (INJECTION FEEDBACK VAL #1 TO #4)


    1. Connect the GTS to the DLC3.

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

    3. Start the engine and warm it up.

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


      Powertrain > Engine and ECT > Data List
      Tester Display
      Injection Feedback Val #1
      Injection Feedback Val #2
      Injection Feedback Val #3
      Injection Feedback Val #4

    5. Read the values.

      Standard
      GTS Display Engine Condition* Normal Value

      Injection Feedback Val #1

      Injection Feedback Val #2

      Injection Feedback Val #3

      Injection Feedback Val #4

      		 Idling

      -3.0 mm3/st to 3.0 mm3/st

      Tech Tips

      *: The A/C switch and all accessory switches should be off, the engine coolant temperature should be 75°C (167°F) or higher and the engine should be idled for 1 minute or more.

      Result
      Result Proceed to

      Injection Feedback Val for at least one cylinder is more than 3 mm3/st and engine vibration is abnormally large

      		 B
      Except above A

      Tech Tips


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

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


    B

    GO TO STEP 10 Click here

    A

  9. CHECK ENGINE SPEED


    1. Start the engine and drive the vehicle until the engine coolant temperature reaches 75°C (167°F) or higher.

    2. Stop the vehicle and allow the engine to idle.

    3. While checking the tachometer, fully depress the accelerator pedal for 5 seconds, and then release it.*1

    4. Repeat procedure *1 5 times.

      Result
      Result Proceed to
      No problems such as sluggishness or variations in the tachometer reading A
      Except above B

    B

    READ VALUE USING GTS (ENGINE SPEED) Click here

    A

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


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

      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

  11. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  12. PERFORM ACTIVE TEST USING GTS (TEST THE FUEL LEAK)


    1. Connect the GTS to the DLC3.

    2. Start the engine and turn the GTS on.

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


      Powertrain > Engine and ECT > 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.

      Click here

      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
      Standard
      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
      Result Proceed to
      The difference between the target fuel pressure and the actual fuel pressure 2 seconds after the Active Test starts is less than 10000 kPa A
      Except above B

    B

    INSPECT INJECTOR ASSEMBLY (INSPECTION FOR VALVE CLOSING PROBLEM) Click here

    A

  13. PERFORM ACTIVE TEST USING GTS (CONTROL THE SELECT CYLINDER FUEL CUT)

    Tech Tips

    Use this Active Test to determine the malfunctioning cylinder.


    1. Connect the GTS to the DLC3.

    2. Start the engine and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Select Cylinder Fuel Cut.


      Powertrain > Engine and ECT > Active Test
      Tester Display
      Control the Select Cylinder Fuel Cut

      Tech Tips


      • If the engine idle speed does not change when an injector assembly is disabled, the cylinder being tested is malfunctioning. Record any malfunctioning cylinders.

      • If the cylinder being tested is normal, there will be a significant change in idle speed when the fuel injection is stopped for that cylinder.

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 15 Click here

  14. INSPECT INJECTOR ASSEMBLY (INSPECTION FOR VALVE CLOSING PROBLEM)


    1. Remove the glow plug for all the cylinders.

      Click here

    2. Visually check if there is fuel on the glow plugs.

      Tech Tips


      • If there is fuel on a glow plug, fuel may be leaking from an injector assembly.

      • After replacing an injector assembly, make sure that the common rail pressure (fuel pressure) is within 5000 kPa (51.0 kgf/cm2, 725 psi) of the target fuel pressure while cranking the engine.

      • If there is fuel on a glow plug, fuel may have mixed with the engine oil. Check the engine oil amount and whether the engine oil smells of diesel fuel. If the oil level is above the full line or the engine oil smells of diesel fuel, replace the engine oil.

    3. Install the glow plug.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  15. REPLACE INJECTOR ASSEMBLY OF MALFUNCTIONING CYLINDER


    1. Replace the injector assembly of the malfunctioning cylinder.

      Click here

      Note


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

  16. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  17. REGISTER INJECTOR COMPENSATION CODE AND PERFORM PILOT QUANTITY LEARNING


    1. Register the injector compensation code.

      Click here


      Powertrain > Engine and ECT > Utility
      Tester Display
      Injector Compensation

    2. Perform the injector pilot quantity learning.

      Click here


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

    NEXT

    GO TO STEP 21 Click here

  18. READ VALUE USING GTS (ENGINE SPEED)


    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 and ECT / Data List / Engine Speed.


      Powertrain > Engine and ECT > Data List
      Tester Display
      Engine Speed

    4. Read the value while cranking and idling the engine.

      Standard
      GTS Display Engine Condition Specified Condition
      Engine Speed Cranking 50 to 400 rpm
      Idling with warm engine 800 to 900 rpm

      Tech Tips

      The value should be the same as the actual engine speed and displayed with no interruption on the GTS.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE CRANKSHAFT POSITION SENSOR Click here

    OK

  19. INSPECT ECM (FUEL PRESSURE SENSOR OUTPUT VOLTAGE)


    1. B002688C98
      *a

      Component with harness connected

      (ECM)

      Connect the positive (+) probe of an oscilloscope to the fuel pressure sensor input terminal of the ECM connector and the negative (-) probe to the body ground.

    2. Turn the ignition switch to ON.

    3. Check for any noise in the waveform when vibration is applied to the wire harness and connectors between the fuel pressure sensor and ECM.

      B0027YSC01
      *1 Engine *2 Engine Wire
      *3 Common Rail Assembly (Fuel Pressure Sensor) *4 Wire to Wire
      *5 ECM - -
      *a Vibration Method (Reference) - -
      B00277OE07
      Standard Voltage
      Tester Connection Condition Specified Condition
      C59-18 (PCR1) - Body ground Vibration is applied to the wire harness and connectors No noise in the waveform
      Result
      Result Proceed to
      MIL comes on or noise present in the waveform B
      Except above A

    B

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - FUEL PRESSURE SENSOR) Click here

    A

  20. CHECK FOR INTERMITTENT PROBLEMS


    1. Check for intermittent problems.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  21. CHECK WHETHER DTC OUTPUT RECURS (DTC P0093)


    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 and ECT / Trouble Codes.

    4. Clear the DTCs.


      Powertrain > Engine and ECT > Clear DTCs

    5. Start the engine.

    6. Warm up the engine (engine coolant temperature is 75°C (167°F) or higher).

    7. Confirm that the shift lever is in neutral and securely apply the parking brake.

    8. Fully depress the accelerator pedal for 5 seconds, and then release it. (*A)

    9. Rev the engine to 3000 rpm and fully release the accelerator pedal immediately after the engine reaches 3000 rpm. (*B)

    10. Repeat procedures (*A) and (*B) 5 times.

      B0025MJE09

    11. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes

    12. Read the DTCs.


      Powertrain > Engine and ECT > Trouble Codes
      OK
      No DTCs are output.
      Result
      Proceed to
      NEXT

    NEXT

    END

  22. REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - FUEL PRESSURE SENSOR)


    1. Repair or replace the harness or connector.

      Result
      Proceed to
      NEXT

    NEXT

  23. INSPECT ECM (FUEL PRESSURE SENSOR OUTPUT VOLTAGE)


    1. B002688C99
      *a

      Component with harness connected

      (ECM)

      Connect the positive (+) probe of an oscilloscope to the fuel pressure sensor input terminal of the ECM connector and the negative (-) probe to the body ground.

    2. Turn the ignition switch to ON.

    3. Check for any noise in the waveform when vibration is applied to the wire harness and connectors between the fuel pressure sensor and ECM.

      Standard Voltage
      Tester Connection Condition Specified Condition
      C59-18 (PCR1) - Body ground Vibration is applied to the wire harness and connectors No noise in the waveform
      Result
      Result Proceed to
      MIL comes on or noise present in the waveform A
      Except above B

    B

    GO TO STEP 21 Click here

    A

  24. REPLACE COMMON RAIL ASSEMBLY


    1. Replace the common rail assembly.

      Click here

      Tech Tips

      Before replacing the common rail 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

  25. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 21 Click here

  26. REPLACE CRANKSHAFT POSITION SENSOR


    1. Replace the crankshaft position sensor.

      Click here

      Tech Tips

      Before replacing the crankshaft position sensor, 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 21 Click here