FUEL SYSTEM (for DPF) ON-VEHICLE INSPECTION


  1. INSPECT FOR FUEL LEAK


    1. Perform the Active Test.


      1. Connect the intelligent tester to the DLC3.

      2. Turn the ignition switch to ON.

      3. Turn the intelligent tester on.

      4. Enter the following menus: Powertrain / Engine and ECT / Active Test.

      5. Perform the Active Test.

        Intelligent Tester Display Test Part Control Range Diagnostic Note
        Test the Fuel Leak Pressurize common rail interior and check for fuel leaks Stop/Start
        • The fuel pressure inside the common rail increases to the specified value and the engine speed increases to 2000 rpm when the Active Test is performed.

        • The above conditions are maintained while the Active Test is being performed.

  2. CHECK PRESSURE DISCHARGE VALVE

    Tech Tips


    • This is the procedure for troubleshooting fuel pressure control malfunctions and combustion problems.

    • Malfunctions can be determined by checking the fuel pressure when performing fuel cut and operating the pressure discharge valve with the intelligent tester.

    • During "Pressure Discharge Valve Check", the intelligent tester measures the fuel pressure while the engine is running, after the engine is stopped, and after the pressure discharge valve operates.


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. A01DVOT

      Turn the intelligent tester on.

      Note

      The following conditions must be met:


      • The engine is idling.

      • The vehicle is stopped.

      • The fuel pressure is not extremely high (below 100000 kPa).

      • The fuel pressure is not extremely low (higher than 26000 kPa).

      • The fuel pressure sensor is normal.

      • The battery voltage is higher than 8 V.

      Tech Tips

      When the common rail pressure is unstable, the fuel pressure may decrease to a level where the test cannot be performed. In this situation, wait until the common rail pressure meets the test condition, and then perform the test.

    4. Enter the following menus: Powertrain / Engine / Utility / Pressure Discharge Valve Check.

    5. A01DYH9

      Press "Next".

    6. A01E0L4

      Press "Next" again to proceed.

    7. A01E32M

      Select "Close to Open Check".

    8. Press "Next".

    9. Read the value of "Open and Engine OFF".

      A01DZYM
      OK
      0.5 MPa or less

      Tech Tips


      • When the system is normal, the value of "Open and Engine OFF" should be at or close to 0 MPa.

      • When the fuel pressure value of "Open and Engine OFF" does not become equal to or less than 0.5 MPa, the pressure discharge valve may be stuck closed.

      • When the fuel pressure values of "Close and Engine OFF" and "Open and Engine OFF" are both 0 MPa, the pressure discharge valve may be stuck open or there may be a fuel leak.

      • Perform "Always Closed Check" if the value is not 0 MPa when the pressure discharge valve is open during "Close to Open Check". If the results are the same as during "Close to Open Check", there is a pressure discharge valve operation malfunction.

        A01DYEAE09
      Text in Illustration
      *1 Fuel Press (Always Closed Check) *2 Fuel Press (Close to Open Check)
      *3 Engine Speed *4 Fuel Cut Operation Signal
      *5 Pressure Discharge Valve Operation Prohibition *6 Pressure Discharge Valve Operation (Always Closed Check)
      *7 Pressure Discharge Valve Operation (Close to Open Check) - -
      *a Fuel Press Recorded Point *b Closed (on)
      *c Open (on) - -
      A01E2TX Pressure Discharge Valve Operation Start - -
  3. BLEED AIR FROM FUEL SYSTEM


    1. A01DYNDE02

      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, the hand pump may be malfunctioning, or the vehicle may have run out of fuel.

      • If air bleeding using the hand pump is incomplete, the common rail pressure does not rise to the pressure range necessary for normal use, and the engine cannot be started.

    2. Check if the engine starts.

      Note


      • Even if air bleeding using the hand pump has been completed, 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 (refer to the procedures above). 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.*1

    8. A01DVKYE05
      Text in Illustration
      *a

      Reference

      (Active Test Operation)

      Enter the following menus: Powertrain / Engine and ECT / Active Test / Test the Fuel Leak.*2

    9. Perform the following test 5 times with on/off intervals of 10 seconds: Active Test / Test the Fuel Leak.*3

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

      A01DYT1E05

      Tech Tips

      When the Active Test "Test the Fuel Leak" is used to change the pump control mode, the actual fuel pressure inside the common rail drops below the target fuel pressure when the Active Test is off, but this is normal and does not indicate a pump malfunction.

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

    12. Read Current DTCs.

    13. Clear the DTCs Click here.

      Tech Tips

      It is necessary to clear the DTCs, as DTC P1604 or P1605 may be stored when air is bled from the fuel system after replacing or repairing fuel system parts.

    14. Repeat steps *1 to *3.

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

    16. Read Current DTCs.

      OK
      No DTCs are output.