ECD SYSTEM (w/ DPF), Diagnostic DTC:P0093

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

DESCRIPTION

The fuel pressure sensor mounted on the common rail converts the fuel pressure inside the common rail into an electrical signal and outputs the signal to the ECM. The ECM controls the supply pump in order to maintain the fuel pressure inside the common rail 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.

P0093
DTC Detection Drive Pattern DTC Detection Condition Trouble Area

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.

Fuel pressure drop before and after 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

  • Suction control valve

  • Common rail assembly

  • Injector assembly

  • Pressure discharge valve (common rail assembly)

  • Fuel pressure sensor (common rail assembly)

  • Crankshaft position sensor

  • Fuel filter element sub-assembly

  • Open or short in injector driver circuit (P062D stored simultaneously)

  • Open or short in injector circuit

  • Injector driver (P062D stored simultaneously)

  • ECM
Related Data List
DTC No. Data List
P0093

  • Fuel Press

  • 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 intelligent tester: Powertrain / Engine and ECT / Data List / Fuel Press.

Reference
Engine Speed Fuel Pressure
Idling Approximately 30000 to 40000 kPa
3000 rpm (No engine load) Approximately 95000 to 115000 kPa

MONITOR DESCRIPTION


MONITOR STRATEGY

Required sensors Fuel pressure sensor
Frequency of operation Continuous
Duration 1 second
MIL operation 1 driving cycle

INSPECTION PROCEDURE

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

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

Tech Tips

Read freeze frame data using the intelligent tester. 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.

A01BDCGE01

Tech Tips


  • The following can be deduced from the above freeze frame data:


    • The common rail fuel pressure dropped suddenly when the engine was being run at a moderate engine speed during engine warmup and DTC P0093 was stored at the point when data set 4 was recorded.

    • Injection Feedback Val #3 is 5.0 mm3/st which is large (the normal value is between -3.0 and 3.0 mm3/st) and indicates that the injector assembly of cylinder 3 may be malfunctioning.

  • Actual cause: In this case, foreign matter in the fuel is stuck inside an injector assembly causing the injector assembly to malfunction temporarily.

    In order to remove the foreign matter in the fuel (the main cause of the problem), the fuel filter case needs to be cleaned and the fuel filter needs to be replaced.

A01BF5FE01
A01BF51E01

Tech Tips

*1: Fuel press suddenly decreases for a moment, and then recovers. This can be seen clearly by comparing it to target common rail pressure.

*2: Injection feedback Val #3 is 5.0 mm3/st which is large (the normal value is between -3.0 and 3.0 mm3/st) and indicates that the injector assembly of cylinder 3 may be malfunctioning.

Reference Values for DTC P0093 Storage Point (Point A)
Data List Value Unit
Engine Speed 1478 rpm
Fuel Press 8900 kPa
Target Common Rail Pressure 65320 kPa
Injection Volume (Point A) 51.26

mm3/st
Injection Volume (Point A`) 9.76

mm3/st
Accel Position 63.67 %
Injection Feedback Val #1 -1.1

mm3/st
Injection Feedback Val #2 -2.5

mm3/st
Injection Feedback Val #3 5.0

mm3/st
Injection Feedback Val #4 -1.8

mm3/st
MIL ON -

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.

    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 intelligent tester to the DLC3.

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

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

    4. Read the DTCs and freeze frame data.

      Result
      Result Proceed to
      P0093 and "P0190, P0192 and/or P0193" are output C
      P0093 and "P0335, P0339 and/or P0340" are output B
      Except above A

    B

    GO TO CRANKSHAFT POSITION SENSOR "A" 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

    CHECK FREEZE FRAME DATA (INJECTION FEEDBACK VAL #1 TO #4) Click here

    A

  4. ADD FUEL


    1. Add fuel.


    NEXT

  5. CHECK WHETHER DTC OUTPUT RECURS (DTC P0093)


    1. A01BEZ7

      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 intelligent tester to the DLC3.

    5. Turn the ignition switch to ON and turn the intelligent tester on.

    6. Clear the DTCs Click here.

    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)

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

      A01BCPLE03

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

    12. Read Current DTCs.


      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 Click here.

    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.

      A01BH6HE02

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

    21. Read Current DTCs.

      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

    CLEAN FUEL FILTER CASE AND REPLACE FUEL FILTER Click here

    A

  7. READ VALUE USING INTELLIGENT TESTER (FUEL PRESS)


    1. Connect the intelligent tester to the DLC3.

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

    3. Clear the DTCs Click here.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press.

    5. Start the engine.

    6. Read the value of Fuel Press while cranking and idling the engine.

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

    B

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

    A

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


    1. Connect the intelligent tester to the DLC3.

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

    5. Read the values.

      Standard
      Tester 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 70°C (158°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

    CLEAN FUEL FILTER CASE AND REPLACE FUEL FILTER Click here

    A

  9. CHECK ENGINE SPEED


    1. Start the engine and drive the vehicle until the engine coolant temperature reaches 60°C (140°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 INTELLIGENT TESTER (ENGINE SPEED) Click here

    A

  10. CLEAN FUEL FILTER CASE AND REPLACE FUEL FILTER


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

      Tech Tips

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


    NEXT

  11. BLEED AIR FROM FUEL SYSTEM


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


    NEXT

  12. 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. 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. A01BF3BE18
      Text in Illustration
      *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 (Fuel Press) 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.

      A01BC0LE01
      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.

      • "Fuel Press" 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 INTELLIGENT TESTER (CONTROL THE CYLINDER #1 TO #4 FUEL CUT)

    Tech Tips

    Use this Active Test to determine the malfunctioning cylinder.


    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 / Control the Cylinder #1 to #4 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.


    NEXT

    REPLACE INJECTOR ASSEMBLY OF MALFUNCTIONING CYLINDER 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 assembly, 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 assembly, 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.


    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 injection pipe.

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

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

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

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


    NEXT

  16. BLEED AIR FROM FUEL SYSTEM


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


    NEXT

  17. 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

    CHECK WHETHER DTC OUTPUT RECURS (DTC P0093) Click here

  18. READ VALUE USING INTELLIGENT TESTER (ENGINE SPEED)


    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 / Engine Speed.

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

      Standard
      Tester Display Engine Condition Specified Condition
      Engine Speed Cranking 50 to 400 rpm
      Idling with warm engine 700 to 800 rpm

      Tech Tips

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


    NG

    REPLACE CRANKSHAFT POSITION SENSOR Click here

    OK

  19. INSPECT ECM (FUEL PRESSURE SENSOR OUTPUT VOLTAGE)


    1. A01BENLE21
      Text in Illustration
      *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.

      A01BCMAE04
      Text in Illustration
      *1 Engine *2 Engine Wire
      *3 Common Rail Assembly (Fuel Pressure Sensor) 4 Wire to Wire
      *5 ECM - -
      *a Vibration Method (Reference) - -
      A01BBNLE03
      Standard Voltage
      Tester Connection Condition Specified Condition
      D76-16 (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. INSPECT FUEL TEMPERATURE SENSOR (SENSOR OUTPUT)


    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 / Fuel Temperature.

    4. Read the value.

      OK
      The value is almost the same as the actual fuel temperature.

      Tech Tips


      • When the engine is stopped and left overnight, the fuel temperature becomes the same as the ambient temperature.

      • If there is a problem with the fuel temperature sensor, and a fuel temperature value lower than the actual fuel temperature is indicated, P0093 may be stored.


    NG

    REPLACE FUEL TEMPERATURE SENSOR Click here

    OK

  21. CHECK FOR INTERMITTENT PROBLEMS


    1. Check for intermittent problems Click here.


    NEXT

    CHECK WHETHER DTC OUTPUT RECURS (DTC P0093) Click here

  22. 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.


    NEXT

    CHECK WHETHER DTC OUTPUT RECURS (DTC P0093) Click here

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


    1. Repair or replace the harness or connector.


    NEXT

  24. INSPECT ECM (FUEL PRESSURE SENSOR OUTPUT VOLTAGE)


    1. A01BENLE21
      Text in Illustration
      *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
      D76-16 (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

    CHECK WHETHER DTC OUTPUT RECURS (DTC P0093) Click here

    A

  25. 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.


    NEXT

  26. BLEED AIR FROM FUEL SYSTEM


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


    NEXT

    CHECK WHETHER DTC OUTPUT RECURS (DTC P0093) Click here

  27. REPLACE FUEL TEMPERATURE SENSOR


    1. Replace the fuel temperature sensor.

      Tech Tips

      Before replacing the fuel temperature sensor, perform a wire harness inspection and if there are any problems with the wire harness, repair or replace it.


    NEXT

  28. CHECK WHETHER DTC OUTPUT RECURS (DTC P0093)


    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. Clear the DTCs Click here.

    5. Start the engine.

    6. Warm up the engine (engine coolant temperature is 70°C (158°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.

      A01BH6HE03

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

    12. Read the DTCs.

      OK
      No DTCs are output.

    NEXT

    END