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On-Vehicle Inspection

  1. CHECK FOR FUEL PUMP OPERATION AND INSPECT FOR FUEL LEAK 
    1. Check fuel pump operation.
      1. Connect the Techstream to the DLC3.
      2. Turn the engine switch on (IG).
        NOTE: Do not start the engine.
      3. Turn the Techstream on.
      4. Enter the following menus. Powertrain / Engine / Active Test / Control the Fuel Pump/Speed.
      5. Check for pressure in the fuel inlet tube from the fuel line Check that sounds of fuel flowing in the fuel tank can be heard If no sounds can be heard, check the instrument panel junction block, fuel pump, ECM and wiring connectors.
    2. Inspect for fuel leaks
      1. Check that there are no fuel leaks from the fuel system after performing any maintenance. If there is a fuel leak, repair or replace parts as necessary.
    3. Turn the engine switch off.
    4. Disconnect the Techstream from the DLC3.
  2. CHECK FUEL PRESSURE 
    1. Using a voltmeter, measure the battery voltage according to the value(s) in the table below.

      Standard Voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Switch Condition Specified Condition
      Positive terminal - Negative terminal Engine switch off 11 to 14 V
    2. Discharge the fuel system pressure (See FUEL SYSTEM )
    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 hose connector cover.
        Fig 1: Locating Fuel Hose Connector Cover
        G05749901Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Pinch the connector and pull the fuel tube (See FUEL SYSTEM )
      CAUTION:
      • Always read Precaution (See PRECAUTION ) before disconnecting the fuel tube connector (for 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 into the engine compartment.
      Fig 2: Pinching Connector And Pulling Fuel Tube
      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
        G05749929Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Pinch the connector and pull the fuel tube.
      CAUTION:
      • Always read Precaution (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 into the engine compartment.
    6. Install SST (pressure gauge) as shown in the illustration.
      Fig 4: Pinching Connector And Pulling Fuel Tube
      G04947864Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 5: Identifying SST (Pressure Gauge)
      G05749931Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      SST 09268-31012 (09268-41500, 90467-13001, 95336-08070), 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 Techstream 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 the fuel tank) If the pressure is lower than the specification, check the fuel hoses, connections and fuel pump (built into the 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 FUEL SYSTEM )
    18. Inspect 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 Techstream on.
    4. Start and warm up the engine.
    5. Run the engine at idle.
    6. Enter the following menus Powertrain / Engine / Data List / 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 
    NOTE: When disconnecting the cable, some systems need to be initialized after the cable is reconnected (See INITIALIZATION ).
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