Fuel Injection System

CHECK INJECTOR COMPENSATION CODE

Check the injector compensation codes.

Result

Result	Proceed to
Except below	A
Compensation codes of the installed injector assemblies are the same as the compensation codes registered in the ECM	B

B

GO TO STEP 3 Click here

A

REGISTER INJECTOR COMPENSATION CODE AND PERFORM PILOT QUANTITY LEARNING

Register the injector compensation codes.

Click here

Perform the pilot quantity learning.

Click here

Result

Proceed to
NEXT

TAKE SNAPSHOT DURING IDLING AND 4000 RPM (PROCEDURE 3)

Connect the GTS to the DLC3.
Start the engine and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Data List / All Data.

Take a snapshot of the following Data List items.

Tech Tips

A snapshot can be used to compare vehicle data from the time of the malfunction to normal data and is very useful for troubleshooting. The data in the list below is that of a normal vehicle, but as the data varies between individual vehicles, this data should only be used for reference.
Check the Data List at idling and at 4000 rpm with no load after the engine is warmed up.

Result

Proceed to
NEXT

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

Check Injection Feedback Val #1 to #4 and Injection Volume in the snapshot taken in procedure 3 when the engine was idling and at 4000 rpm with no load.

Result

Result	Proceed to
Injection Feedback Val for at least one cylinder is more than 3.0 mm³/st	A
Injection Volume is 5 mm³/st or less at 4000 rpm	B
Except above	C

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 23 Click here

C

READ VALUE USING GTS (INJECTION VOLUME) Click here

A

PERFORM ACTIVE TEST USING GTS (CHECK THE CYLINDER COMPRESSION)

Tech Tips

Use this Active Test to help determine whether a cylinder has compression loss or not.

Connect the GTS to the DLC3.
Start the engine and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Check the Cylinder Compression / Compression / Engine Speed of Cyl #1 to #4.

Powertrain > Engine > Active Test

Tester Display

Check the Cylinder Compression

Tester Display
Check the Cylinder Compression

Check the engine speed during the Active Test.

Result

Result	Proceed to
Except below	A
The values of Engine Speed Cyl #1 to #4 are within +/-10 rpm of each other.	B

Tech Tips

When cranking, if the speed of a cylinder is approximately 100 rpm higher than the other cylinders, there is probably a complete loss of compression in that cylinder.

B

GO TO STEP 7 Click here

A

CHECK CYLINDER COMPRESSION PRESSURE

Check the cylinder compression pressure.

Click here

Tech Tips

When compression is low, there may be cracks in the piston or the injector assembly may be installed improperly.

Result

Proceed to
OK
NG

NG

CHECK AND REPLACE ENGINE ASSEMBLY Click here

OK

PERFORM PILOT QUANTITY LEARNING (DETAIL)

Perform the pilot quantity learning (detail).

Click here

Result

Proceed to
NEXT

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

Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Start the engine and warm it up.

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

Powertrain > Engine > Data List

Tester Display
Injection Feedback Val #1
Injection Feedback Val #2
Injection Feedback Val #3
Injection Feedback Val #4

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 3.0 mm³/st	A
Except above	B

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 11 Click here

A

REPLACE INJECTOR ASSEMBLY OF MALFUNCTIONING CYLINDER

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.

Result

Proceed to
NEXT

GO TO STEP 24 Click here

CHECK AND REPLACE ENGINE ASSEMBLY

Check and replace the engine assembly.

Result

Proceed to
NEXT

PERFORM ACTIVE TEST USING GTS (TEST THE FUEL LEAK)

Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.

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.

Powertrain > Engine > Active Test

Active Test Display
Test the Fuel Leak

Data List Display
Target Common Rail Pressure
Fuel Press
Target Pump SCV Current

Start the engine.
Take a snapshot with the GTS during the Active Test.

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.

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.

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 (102.0 kgf/cm², 1451 psi).

Result

Proceed to
NG
OK*

Note

*: Even when the results of the Active Test are normal, take a snapshot of vehicle data when the vehicle is accelerating. If "Fuel Press" does not follow "Target Common Rail Pressure", proceed to step 12.

If "Fuel Press" does not follow "Target Common Rail Pressure", the fuel filter may be clogged.

Tech Tips

"Target Common Rail Pressure" means target fuel pressure controlled by the ECM.
"Fuel Press" means actual fuel pressure in common rail assembly.
If the pressure discharge valve mounted on the common rail assembly is malfunctioning, the actual fuel pressure may change as indicated by "Pressure Discharge Valve Malfunctioning" in the illustration.
The pressure discharge valve operates to discharge fuel pressure when the internal pressure of the common rail exceeds the target fuel pressure.
There are 2 fuel pressure sensor circuits and both of them display the same value. If the difference between Common Rail Pressure and Common Rail Press Sens 2 exceeds 10000 kPa (102 kgf/cm², 1451 psi) for 2 seconds or more, it is necessary to inspect or repair the wiring for the fuel pressure sensor.

OK*

GO TO STEP 17 Click here

NG

CHECK COMMON RAIL ASSEMBLY (PRESSURE DISCHARGE VALVE)

Connect the GTS to the DLC3.
Start the engine.
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Utility / Pressure Discharge Valve Check.

Powertrain > Engine > Utility

Tester Display

Pressure Discharge Valve Check
Select "Always Closed Check".
Press "Next".

Tester Display
Pressure Discharge Valve Check

Read the Value of fuel pressure values.

OK
Fuel pressure is properly maintained.

Tech Tips

If the fuel pressure cannot be maintained, the pressure discharge valve may not have a tight seal.
If the fuel pressure is being properly maintained, there are no problems with the sealing properties of the high-pressure fuel system. Therefore, an insufficient supply of fuel due to the fuel filter being clogged, or squashed or blocked low-pressure fuel pipes or hoses may be causing the reduction in common rail pressure.

Result

Proceed to
OK
NG

NG

REPLACE COMMON RAIL ASSEMBLY (PRESSURE DISCHARGE VALVE) Click here

OK

INSPECT CLOGGED FUEL PIPE

Connect the GTS to the DLC3.
Start the engine and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Common Rail (All).
With no load after the engine is warmed up, take a snapshot when idling and vehicle was accelerating with the accelerator pedal fully depressed in 2nd gear.

Check the Target Common Rail Pressure and Fuel Press value.

Result

Result	Proceed to
While idling the vehicle, "Fuel Press" deviates from the normal range and varies periodically with a period of approximately 2 seconds or more*1	A
"Fuel Press" is normal while idling the vehicle, but "Fuel Press" does not follow "Target Common Rail Pressure" when the accelerator pedal is fully depressed in 2nd gear*2	A
Except above	B

Note

*1: The cause may be a squashed or blocked fuel pipe or hose.
*2: The cause may be a clogged fuel filter element assembly.

B

GO TO STEP 18 Click here

A

REPAIR OR REPLACE CLOGGED FUEL LINE

Repair or replace the clogged (including frozen fuel) fuel pipe.

Replace the fuel filter element assembly.

Tech Tips

If "Common Rail Pressure" does not follow "Target Common Rail Pressure" when the accelerator pedal is fully depressed in 2nd gear, replace the fuel filter element assembly.

Result

Proceed to
NEXT

GO TO STEP 16 Click here

REPLACE COMMON RAIL ASSEMBLY (PRESSURE DISCHARGE VALVE)

Replace the common rail assembly.

Click here

Result

Proceed to
NEXT

BLEED AIR FROM FUEL SYSTEM

Bleed the air from the fuel system.

Click here

Result

Proceed to
NEXT

READ VALUE USING GTS (FUEL PRESS AND TARGET COMMON RAIL PRESSURE)

Check Fuel Press and Target Common Rail Pressure in the snapshot taken in procedure 3 when the engine was idling.

Result

Result	Proceed to
Except above	A
Difference between Fuel Press and Target Common Rail Pressure is 5000 kPa (51.0 kgf/cm², 725 psi) or more	B

A

END

B

REPLACE SUCTION CONTROL VALVE

Replace the suction control valve.

Click here

Result

Proceed to
NEXT

BLEED AIR FROM FUEL SYSTEM

Bleed the air from the fuel system.

Click here

Result

Proceed to
NEXT

PERFORM SUPPLY PUMP INITIALIZATION

Perform supply pump initialization.

Click here

Result

Proceed to
NEXT

CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

Result

Proceed to
NEXT

END

READ VALUE USING GTS (INJECTION VOLUME)

Check Injection Volume in the snapshot taken in procedure 3 when the engine was idling.

Result

Result	Proceed to
Injection Volume while idling after engine warm up is 15 mm³/st or more	A
Except above	B

Tech Tips

Check that PM forced regeneration is not being performed.

B

GO TO STEP 11 Click here

A

REPLACE INJECTOR ASSEMBLIES OF ALL CYLINDERS

Replace the injector assemblies of all cylinders.

Click here

Note

When replacing the injector assembly for a cylinder, always be sure to use a new injection pipe. 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.

Result

Proceed to
NEXT

REPLACE FUEL FILTER ELEMENT ASSEMBLY

Replace the fuel filter element assembly.

Click here

Result

Proceed to
NEXT

BLEED AIR FROM FUEL SYSTEM

Bleed the air from the fuel system.

Click here

Result

Proceed to
NEXT

REGISTER INJECTOR COMPENSATION CODE AND PERFORM PILOT QUANTITY LEARNING

Register the injector compensation codes.

Click here

Perform the pilot quantity learning.

Click here

Result

Proceed to
NEXT

GO TO STEP 11 Click here

ECD SYSTEM(for DPF) Fuel Injection System