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On-Vehicle Inspection

  1. CHECK FUEL PUMP OPERATION 
    1. Connect a LEXUS hand-held tester or OBD II scan tool to the DLC3.
      2. Fig 1: Connecting Hand-Held Tester To DLC3
      G00920295Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the ignition switch ON, and press the LEXUS hand-held tester OBD II scan tool main switch ON.
      NOTE: Do not start the engine. 
    3. Select the ACTIVE TEST mode on the LEXUS hand-held tester or OBD II scan tool.
    4. Please refer to the LEXUS hand-held tester or OBD II scan tool operator's manual for further details.
    5. If you have no LEXUS hand-held tester or OBD II scan tool, connect the positive (+) and negative (-) leads from the battery to the fuel pump connector. (See step  3)
    6. Disconnect the fuel return hose from the clamp on the V-bank cover.
    7. Remove the 2 bolts, nuts and V-bank cover.
    8. Check that the pulsation damper screw pop up when the fuel pump operates.
      Fig 2: Identifying Screw Of Pulsation Damper
      G00920296Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If operation is not as specified, check following parts:

      • Fusible link
      • Fuses
      • EFI main relay
      • Fuel pump
      • ECM
      • Wiring connections
    9. Turn the ignition switch OFF.
    10. Disconnect the LEXUS hand-held tester or OBD II scan tool from the DLC3.
  2. CHECK FUEL PRESSURE 
    1. Check the battery positive voltage is above 12 V.
    2. Disconnect the negative (-) terminal cable from the battery.
    3. Remove the front fuel pipe from the LH delivery pipe. (See REMOVAL )
    4. Install the front fuel pipe and SST (pressure gauge) to the delivery pipe with the 3 lower gasket and SST (adaptor).
      Fig 3: Connecting Pressure Gauge
      G00920297Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. SST 09268-45014 (09268-41190, 90405-06167)
      2. Torque: 39 N.m (400 kgf.cm, 29 ft.lbf) 
    5. Wipe off any splattered gasoline.
    6. Reconnect the negative (-) terminal cable to the battery.
    7. Connect a LEXUS hand-held tester or OBD II scan tool to the DLC3 (See ( a) to ( e) step  1 on the check fuel pump operation).
    8. Measure the fuel pressure.
      1. Fuel pressure: 265 - 304 kPa (2.7 - 3.1 kgf/cm 2  , 38 - 44 psi) 

      If pressure is higher than the specification, replace the fun pressure regulator.

      If pressure is lower than the specification, check these parts:

      • Fuel hoses and connections
      • Fuel pump
      • Fuel filter
      • Fuel pressure regulator
    9. Disconnect the LEXUS hand-held tester or OBD II scan tool from the DLC3.
    10. Start the engine.
    11. Measure the fuel pressure at idle.
      1. Fuel pressure: 265 - 304 kPa (2.7 - 3.1 kgf/cm 2  , 38 - 44 psi) 
    12. Stop the engine.
    13. Check that the fuel pressure remains in the specification below for 5 minutes after the engine stop.
      1. Fuel pressure: 147 kPa (1.5 kgf/cm 2  , 21 psi) or more 

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

    14. After checking the fuel pressure, disconnect the negative (-) terminal cable from the battery and carefully remove the SST to prevent gasoline from splashing.
      1. SST 09268-45014 
    15. Reinstall the front fuel pipe to the LH delivery pipe. (See INSTALLATION )
    16. Reconnect the negative (-) terminal cable to the battery.
    17. Check for fuel leaks. (See PRECAUTION )
    18. Reinstall the V-bank cover with the 2 bolts and nuts.
    19. Reconnect the fuel return hose to the clamp on the V-bank cover.
  3. INSPECT FUEL PUMP 
    1. Remove the No.1 rear seats.
    2. Remove the 2 rear door scuff plates, the step plates and the rear seat lock covers.
    3. Pull off the front and rear floor carpets.
    4. Remove the 2 screws and the rear floor service hole cover.
    5. Disconnect the fuel pump & sender gauge connector.
      6. Fig 4: Inspecting Fuel Pump
      G00920298Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Using an ohmmeter, measure the resistance between terminal 4 and 5.
      1. Resistance: 0.2 - 3.0 Ω at 20°C (68°F) 

      If the resistance is not as specified, replace the fuel pump and/or the lead wire.

      Fig 5: Measuring Resistance Between Terminal 4 & 5
      G00920299Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. Inspect the fuel pump operation.

      Connect the battery positive (+) lead to terminal 4 of the connector, and the battery negative (-) lead to terminal 5. Check that the fuel pump operates.

      NOTE:
      • These tests must be done quickly (within 10 seconds) to prevent the coil burning out. 
      • Keep the fuel pump as far away from the battery as possible. 
      • Always change the connection on the battery side. 

      If operation is not as specified, replace the fuel pump and/or lead wire.

    8. Reconnect the fuel pump & sender gauge connector.
    9. Reinstall the rear floor service hole cover with the 2 screws.
    10. Reinstall the front and rear floor carpets.
    11. Remove the 2 rear door scuff plates, the step plates and the rear sear lock covers.
    12. Reinstall the No.1 rear seats.
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