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On-Vehicle Inspection

  1. CHECK FUEL PUMP OPERATION 
    1. Connect a hand-held tester to the DLC3.
      2. Fig 1: Connecting Hand-Held Tester To DLC3
      G02949192Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the ignition switch ON and hand-held tester main switch ON.
      NOTE: Do not start the engine.
    3. Select the following menu items: DIAGNOSIS/ENHANCED OBD II/ACTIVE TEST/FUEL PUMP/SPD.
    4. Please refer to the hand-held tester operator's manual for further details.
    5. If you have no hand-held tester, connect the positive (+) and negative (-) leads from the battery to the fuel pump connector (See step  3).
    6. Check that the pulsation damper screw rises up when the fuel pump operates.

      If there is no pressure, check the fusible link, fuses, EFI main relay, fuel pump ECU, fuel pump, ECM and wiring connections.

      Fig 2: Checking Pulsation Damper Screw Rises Up When Fuel Pump Operates
      G02949193Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. Turn the ignition switch OFF.
    8. Disconnect the hand-held tester from the DLC3.
  2. CHECK FUEL PRESSURE 
    1. Check the battery positive voltage is above 12V.
    2. Disconnect the negative (-) terminal cable from the battery.
    3. Remove the union bolt and 2 gaskets, and disconnect the fuel inlet hose from the fuel pipe support.
      NOTE:
      • Put a shop towel under the fuel pipe support.
      • Slowly loosen the union bolt.
      Fig 3: Removing Union Bolt Of Fuel Inlet Hose Clamp
      G02949194Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Install the fuel inlet hose and SST (pressure gauge) to the fuel pipe support with the 3 gaskets and SST (union and adapter).
      1. SST 09268-45014 (09268-41190, 90405-06167)
      2. Torque: 29 N.m (300 kgf.cm, 21 ft.lbf) 
      Fig 4: Installing Fuel Inlet Hose And SST (Pressure Gauge) To Fuel Pipe Support With Gaskets And SST (Union And Adapter)
      G02949195Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Wipe off any splattered gasoline.
    6. Connect a hand-held tester to the DLC3 (See step  1 in check fuel pump operation ( a) to ( e).
      Fig 5: Connecting Hand-Held Tester To DLC3
      G02949196Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. Measure the fuel pressure.

      Fuel pressure: 

      304-343 kPa (3.1-3.5 kgf/cm 2  , 44-50 psi) 

      If pressure is high, replace the fuel pressure regulator.

      If pressure is low, check the fuel hoses and connections, fuel pump, fuel filter and fuel pressure regulator.

    8. Disconnect the hand-held tester from the DLC3.
    9. Start the engine.
    10. Measure the fuel pressure at idle.

      Fuel pressure: 

      304-343 kPa (3.1-3.5 kgf/cm 2  , 44-50 psi) 

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

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

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

    13. After checking fuel pressure, disconnect the negative (-) terminal cable from the battery and carefully remove SST to prevent gasoline from splashing.
      1. SST 09268-45014
    14. Reconnect the fuel inlet hose to the fuel pipe support with 2 new gaskets and the union bolt.
      1. Torque: 29 N.m (300 kgf.cm, 21 ft.lbf) 
    15. Reconnect the negative (-) terminal cable to the battery.
    16. Check for fuel leaks.
  3. INSPECT FUEL PUMP 
    1. Remove the rear seat cushion.
    2. Remove the 3 cap nuts and floor service hole cover.
    3. Disconnect the fuel pump & sender gauge connector.
    4. Using an ohmmeter, measure the resistance between terminals 4 and 5.

      Resistance: 0.2-3.0 Ω at 20°C (68°F) 

      If the resistance is not as specified, replace the fuel pump.

      Fig 6: Measuring Resistance Between Terminals 4 And 5
      G02949197Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Inspect the fuel pump operation.

      Connect the positive (+) lead from the battery to terminal 4 of the connector, and the 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 do the switching at the battery side.
      Fig 7: Inspecting Fuel Pump Operation
      G02949198Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If operation is not as specified, replace the fuel pump.

    6. Reconnect the fuel pump & sender gauge connector.
    7. Reinstall the floor service hole cover with the cap nuts.
    8. Reinstall the rear seat cushion.
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