Dtc P0093 Fuel System Leak Detected - Large Leak

DESCRIPTION

MONITOR DESCRIPTION

INSPECTION PROCEDURE

CHECK FOR FUEL LEAKS (IN HIGH-PRESSURE AREAS)

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

CHECK FUEL RECEIVER GAUGE (AMOUNT OF FUEL)

ADD FUEL

CHECK WHETHER DTC OUTPUT RECURS (DTC P0093)

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

READ VALUE USING GTS (COMMON RAIL PRESSURE)

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

CHECK ENGINE SPEED

REPLACE FUEL FILTER ELEMENT ASSEMBLY

BLEED AIR FROM FUEL SYSTEM

PERFORM ACTIVE TEST USING GTS (TEST THE FUEL LEAK)

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

INSPECT INJECTOR ASSEMBLY (INSPECTION FOR VALVE CLOSING PROBLEM)

REPLACE INJECTOR ASSEMBLY OF MALFUNCTIONING CYLINDER

BLEED AIR FROM FUEL SYSTEM

REGISTER INJECTOR COMPENSATION CODE AND PERFORM PILOT QUANTITY LEARNING

READ VALUE USING GTS (ENGINE SPEED)

INSPECT ECM (FUEL PRESSURE SENSOR OUTPUT VOLTAGE)

CHECK FOR INTERMITTENT PROBLEMS

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

INSPECT ECM (FUEL PRESSURE SENSOR OUTPUT VOLTAGE)

REPLACE COMMON RAIL ASSEMBLY

BLEED AIR FROM FUEL SYSTEM

REPLACE CRANKSHAFT POSITION SENSOR

CHECK WHETHER DTC OUTPUT RECURS (DTC P0093)

DTC 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 (LandCruiser RM000000XSN04PX.html).

HINT:

1. If the drop in the internal fuel pressure is large when injecting fuel, the ECM interprets this as a fault and stores P0093.
   
2. If P0093 is present, refer to "Diagnostic Trouble Code (DTC) Table for Common Rail System" (LandCruiser RM000000XSN04PX.html).
   

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 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 circuit ECM

Related Data List

DTC No.	Data List
P0093	Common Rail Pressure Target Common Rail Pressure

HINT:

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	Fuel Pressure
Idling	Approximately 30000 to 50000 kPa
3000 rpm (No engine load)	Approximately 80000 to 110000 kPa

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, PM forced regeneration and fuel supply pump assembly operation is prohibited. The ECM continues operating in fail-safe mode until the engine switch is turned off.

INSPECTION PROCEDURE

NOTICE:

1. Soon after starting the engine, visually check for fuel leaks in the fuel line.
   
2. After replacing the ECM, the new ECM needs registration (LandCruiser RM0000012XK0AVX.html) and initialization (LandCruiser RM000000TIN08IX.html).
   
3. After replacing an injector assembly, the ECM needs registration (LandCruiser RM0000012XK0AVX.html).
   

HINT:

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.

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 GTS to the DLC3.
   

2. Turn the engine switch on (IG) and turn the GTS on.
   

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

4. Read the DTCs and freeze frame data.
   
   

   Result

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

B	GO TO DTC CHART (LandCruiser RM0000031HW07PX.html)
C	GO TO FUEL RAIL PRESSURE SENSOR CIRCUIT (LandCruiser RM0000018800CCX.html)

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

A

4.ADD FUEL

1. Add fuel.
   

NEXT

5.CHECK WHETHER DTC OUTPUT RECURS (DTC P0093)

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

   NOTICE:

   1. Hand pump pumping speed: Max. 2 strokes/sec.
      
   2. The hand pump must be pushed with a full stroke during pumping.
      
   3. When the fuel pressure at the fuel supply pump inlet port reaches a saturated pressure, the hand pump resistance increases.
      
   4. 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.
      
   5. If the priming pump does not become harder to push even after pumping continuously 200 times or more, the pipe between the fuel tank and the fuel filter may have a leak, there may be an insufficient amount of fuel or the priming pump may be malfunctioning.
      
   6. 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.
   

   NOTICE:

   1. Even if air bleeding completes with the priming pump, the vehicle may take 10 seconds or more to start.
      
   2. Do not crank the engine continuously for more than 20 seconds. The battery may be discharged.
      
   3. 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 engine switch off.
   

4. Connect the GTS to the DLC3.
   

5. Turn the engine switch on (IG) and turn the GTS on.
   

6. Clear the DTCs (LandCruiser RM000000PDK1ENX.html).
   

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)
    

    
    
    
    

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

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 (LandCruiser RM000000PDK1ENX.html).
    

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.
    

    
    
    
    

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

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

   HINT:

   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

A

7.READ VALUE USING GTS (COMMON RAIL PRESSURE)

1. Connect the GTS to the DLC3.
   

2. Turn the engine switch on (IG) and turn the GTS on.
   

3. Clear the DTCs (LandCruiser RM000000PDK1ENX.html).
   

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

A

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

1. Connect the GTS to the DLC3.
   

2. Turn the engine switch on (IG) 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.
   

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

   HINT:

   *: 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

   HINT:

   1. 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.
      
   2. 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

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	Go to step 18

A

10.REPLACE FUEL FILTER ELEMENT ASSEMBLY

1. Replace the fuel filter element assembly (LandCruiser RM0000045HW008X.html).
   

NEXT

11.BLEED AIR FROM FUEL SYSTEM

1. Bleed the air from the fuel system (LandCruiser RM000002SY803FX_01_0002.html).
   

NEXT

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

1. Connect the GTS to the DLC3.
   

2. Turn the engine switch on (IG) 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.
   

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 (LandCruiser RM0000012X109TX.html).
   

   HINT:

   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.

   
   
   
   

   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.
   

   HINT:

   1. "Target Common Rail Pressure" is the target fuel pressure controlled by the ECM.
      
   2. "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	Go to step 14

A

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

HINT:

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.
   

   HINT:

   1. If the engine idle speed does not change when an injector assembly is disabled, the cylinder being tested is malfunctioning. Record any malfunctioning cylinders.
      
   2. 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	Go to step 15

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

1. Remove the glow plug for all the cylinders (LandCruiser RM000000JIT01FX.html).
   

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

   HINT:

   1. If there is fuel on a glow plug assembly, fuel may be leaking from an injector assembly.
      
   2. 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.
      
   3. 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 assembly (LandCruiser RM000000JIQ01IX.html).
   

NEXT

15.REPLACE INJECTOR ASSEMBLY OF MALFUNCTIONING CYLINDER

1. Replace the injector assembly of the malfunctioning cylinder (LandCruiser RM000005UHS000X.html).
   

   NOTICE:

   1. 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.
      
   2. 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.
      
   3. 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.
      
   4. If an injector assembly deteriorates and malfunctions, other problems such as knocking, rough idle, etc. may occur.
      
   5. 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.
      

NEXT

16.BLEED AIR FROM FUEL SYSTEM

1. Bleed the air from the fuel system (LandCruiser RM000002SY803FX_01_0002.html).
   

NEXT

17.REGISTER INJECTOR COMPENSATION CODE AND PERFORM PILOT QUANTITY LEARNING

1. Register the injector compensation code (LandCruiser RM0000012XK0AVX_02_0003.html).
   

2. Perform the injector pilot quantity learning (LandCruiser RM0000012XK0AVX_02_0009.html).
   

NEXT	Go to step 26

18.READ VALUE USING GTS (ENGINE SPEED)

1. Connect the GTS to the DLC3.
   

2. Turn the engine switch on (IG) and turn the GTS 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:

   
   

   GTS Display	Engine Condition	Specified Condition
   Engine Speed	Cranking	50 to 400 rpm
   	Idling with warm engine	650 to 750 rpm

   HINT:

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

NG	Go to step 25

OK

19.INSPECT ECM (FUEL PRESSURE SENSOR OUTPUT VOLTAGE)

1. 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.
   

   Text in Illustration

   *a	Component with harness connected (ECM)

2. Turn the engine switch on (IG).
   

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.
   

   
   
   
   
   

   Text in Illustration

   *1	Engine	*2	Common Rail Assembly (Fuel Pressure Sensor)
   *3	Engine Wire	*4	Wire to Wire
   *5	ECM	-	-
   *a	Vibration Method (Reference)	-	-

   
   
   
   
   

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   C151-18 (PCR1) - Body ground	Vibration is applied to the wire harness and connectors	No noise in the waveform

   
   

   Result

   Result	Proceed to
   MIL does not come on	B
   MIL come on	A

B	Go to step 21

A

20.CHECK FOR INTERMITTENT PROBLEMS

1. Check for intermittent problems (LandCruiser RM000000PDQ1A0X.html).
   

NEXT	Go to step 26

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

1. Repair or replace the harness or connector.
   

NEXT

22.INSPECT ECM (FUEL PRESSURE SENSOR OUTPUT VOLTAGE)

1. 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.
   

   Text in Illustration

   *a	Component with harness connected (ECM)

2. Turn the engine switch on (IG).
   

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
   C151-18 (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 26

A

23.REPLACE COMMON RAIL ASSEMBLY

1. Replace the common rail assembly (LandCruiser RM000005UI0000X.html).
   

   HINT:

   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

24.BLEED AIR FROM FUEL SYSTEM

1. Bleed the air from the fuel system (LandCruiser RM000002SY803FX_01_0002.html).
   

NEXT	Go to step 26

25.REPLACE CRANKSHAFT POSITION SENSOR

1. Replace the crankshaft position sensor (LandCruiser RM0000013Z6020X.html).
   

   HINT:

   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

26.CHECK WHETHER DTC OUTPUT RECURS (DTC P0093)

1. Connect the GTS to the DLC3.
   

2. Turn the engine switch on (IG) and turn the GTS on.
   

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

4. Clear the DTCs (LandCruiser RM000000PDK1ENX.html).
   

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.
    

    
    
    
    

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

12. Read the DTCs.
    

    OK:

    No DTCs are output.
    

NEXT
END