LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2008 >> LS 460L >> Repair and Diagnosis >> Engine Performance >> Fuel Delivery >> Fuel System >> On-Vehicle Inspection
April 5, 2026: LEMON Manuals is launched! Read the announcement.

On-Vehicle Inspection

  1. CHECK FUEL PUMP OPERATION AND FOR FUEL LEAKS 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
      NOTE: Do not start the engine.
    3. Turn the tester ON.
    4. Enter the following menus: Powertrain / Engine / Active Test / Control the Fuel Pump Speed.
    5. Check the fuel pump operation.
      1. Check for pressure in the fuel inlet tube from the fuel line. Check that the sound of fuel flowing in the fuel tank can be heard. If no sound can be heard, check the integration relay, fuel pump, ECM and wiring connector.
    6. Check for fuel leaks.
      1. Check that there are no fuel leaks anywhere on the system after performing maintenance. If there is a fuel leak, repair or replace parts as necessary.
  2. CHECK FUEL PRESSURE 
    1. Check that the battery positive voltage is above 12 V.
    2. Discharge the fuel system pressure (see PRECAUTION  ).
    3. Disconnect the cable from the negative (-) battery terminal.
    4. When checking the fuel pressure of the direct injection side:

      Disconnect the fuel pump main tube.

      1. Remove the fuel pipe clamp.
        Fig 1: Locating Fuel Tube Connector (Quick Type A)
        G04947837Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Pinch the connector and pull the fuel tube (see PRECAUTION  ).
        CAUTION:
        • Always read the precautions (see PRECAUTION  ) before disconnecting the fuel tube connector (quick type A).
        • The fuel tube may spray fuel as a result of pressure that remains in the tube. Do not allow fuel to be sprayed in the engine compartment.
          Fig 2: Pinching Connector
          G04947862Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. When checking the fuel pressure of the port injection side: Disconnect the fuel pump main tube.
      1. Remove the fuel pipe clamp.
        Fig 3: Locating Fuel Pipe Clamp
        G04947863Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Pinch the connector and pull the fuel tube.
        CAUTION:
        • Always read the precautions (see PRECAUTION  ) before disconnecting the fuel tube connector (quick type A).
        • The fuel tube may spray fuel as a result of pressure that remains in the tube. Do not allow fuel to be sprayed in the engine compartment.
        • Fig 4: Pinching Connector
          G04947864Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Install SST (pressure gauge) as shown in the illustration.
      Fig 5: Installing SST (Pressure Gauge)
      G04947865Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      SST 09268-31012 (90467-13001, 95336-08070, 09268-41500), 09268-45014 (09268-41200, 09268-41220, 09268-41250) 

    7. Wipe off any gasoline.
    8. Reconnect the cable to the negative (-) battery terminal.
    9. Operate the fuel pump.
      1. Connect the Techstream to the DLC3.
      2. Turn the engine switch on (IG).
        NOTE: Do not start the engine.
      3. Turn the tester ON.
      4. Enter the following menus: Powertrain / Engine / Active Test / Control the Fuel Pump Speed.
    10. Measure the fuel pressure.

      Standard fuel pressure: 

      196 to 588 kPa (2 to 6 kgf/cm 2  , 28 to 85 psi) 

      If the fuel pressure is higher than the specification, replace the fuel pump (built into fuel tank).

      If the pressure is lower than the specification, check the fuel hoses, connections and fuel pump (built into fuel tank).

    11. Connect the Techstream to the DLC3.
    12. Start the engine.
    13. Measure the fuel pressure at idle.

      Standard fuel pressure: 

      196 to 588 kPa (2 to 6 kgf/cm 2  , 28 to 85 psi) 

      If the pressure is not as specified, check the fuel pump and injectors.

    14. Stop the engine.
    15. Check that the fuel pressure remains as specified for 5 minutes after the engine has stopped.

      Standard fuel pressure: 

      147 kPa (1.5 kgf/cm 2  , 21 psi) or more 

      If the pressure is not as specified, check the fuel pump or injectors.

    16. After checking the fuel pressure, disconnect the cable from the negative (-) battery terminal and carefully remove SST and the fuel tube connector to prevent fuel from spilling.
    17. Reconnect the fuel pump main tube (see PRECAUTION  ).
    18. Check for fuel leaks.
  3. CHECK FUEL PRESSURE (for High Pressure) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the tester ON.
    4. Start and warm up the engine.
    5. Run the engine at idle.
    6. Enter the following menus: Powertrain / Engine / Data List / All Data / Fuel Press.
    7. Check the high pressure side fuel pressure.

      Standard fuel pressure: 

      3.5 to 4.5 MPa (35.7 to 45.9 kgf/cm 2  , 508 to 653 psi) 

      If the pressure is not as specified, check the fuel pump, high pressure side fuel pump, fuel pressure sensor and wirings.

    8. Stop the engine.
  4. PERFORM INITIALIZATION 
    1. Perform initialization (see INITIALIZATION ).
      NOTE: Certain systems need to be initialized after disconnecting and reconnecting the cable to the negative (-) battery terminal.