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Engine Fuel System: Precaution

  1. EXPRESSIONS OF IGNITION SWITCH 

    The type of ignition switch used on this model differs according to the specifications of the vehicle. The expressions listed in the table below are used in this section.

    IGNITION SWITCH EXPRESSIONS CHART

    Expression / Switch Type Ignition Switch (position) Engine Switch (condition)
    Ignition Switch off LOCK Off
    Ignition switch on (IG) ON On (IG)
    Ignition Switch on (ACC) ACC On (ACC)
    Engine Start START Start
  2. PRECAUTION 
    1. Before inspecting and repairing the fuel system, disconnect the negative (-) battery cable.
    2. Do not smoke or work near fire when handling the fuel system.
    3. Keep gasoline away from rubber or leather parts.
  3. DISCHARGE FUEL SYSTEM PRESSURE 
    CAUTION:
    • Perform the following procedures to prevent fuel from spilling out before removing any fuel system parts.
    • Pressure will still remain in the fuel line even after performing the following procedures. When disconnecting the fuel line, cover with a shop rag or a piece of cloth to prevent fuel from spraying or spewing out.
    1. Disconnecting the fuel pump connector.
      1. Remove the rear seat cushion assy.
      2. Remove the rear floor service hole cover.
      3. Disconnect the fuel pump connector.
      4. Start the engine.
      5. After the engine stops, turn the ignition switch off.

        HINT:

        DTC P0171/25 (fuel problem) and/or P0191/49 (fuel pressure sensor signal error) may be detected.

      6. Crank the engine again. Check that the engine does not start.
      7. Remove the fuel tank cap to discharge pressure from the fuel tank.
      8. Disconnect the negative (-) battery terminal cable.
      9. Reconnect the fuel pump connector.
        Fig 1: Disconnect Negative (-) Battery Terminal Cable
        G02974088Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      10. Install the rear floor service hole cover.
      11. Install the rear seat.
  4. FUEL SYSTEM 
    1. When disconnecting the high fuel pressure line, a large amount of gasoline will spill out, so observe the following procedures:
      1. Discharge the fuel system pressure, (step  3)
      2. Disconnect the fuel pump tube (see Removal & Installation and Disassembly & Reassembly ).
      3. Drain the fuel that remains inside the fuel pump tube.
      4. To protect the disconnected fuel pump tube from damage and contamination, cover it with a plastic bag.
      5. Put a container under the connection part.
        Fig 2: Covering Fuel Pump With Plastic Bag
        G02974089Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Observe the following precautions when removing and installing fuel injectors:
      1. Never reuse the O-ring.
      2. When placing a new O-ring on the injector, do not damage the O-ring.
      3. Coat new O-ring with spindle oil or gasoline before installing.
        NOTE: Do not use engine oil, gear oil or brake oil.
        Fig 3: Identifying Correct Way Of Removing & Installing Fuel Injectors
        G02974090Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Install the injector to the delivery pipe and lower intake manifold as shown in the illustration.
      NOTE: Before installing the injector, be sure to apply grease or gasoline on the place where the delivery pipe or cylinder head contacts the O-ring of the injector.
      Fig 4: Installing Injector To Delivery Pipe
      G02974091Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Observe the following precautions when disconnecting the fuel tube connectors (Quick type A):
      1. Remove the fuel pipe clamp No. 1.
        Fig 5: Removing Fuel Pipe Clamp No. 1
        G02974092Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Check that there is no dirt or other foreign objects on the pipe and around the connector before disconnecting them. Clean them if necessary.
      3. Disconnect the connector from the pipe by hand.
      4. When the connector and the pipe are stuck, push in and pull on the connector to release it and pull the connector out of the pipe carefully.
      5. Check that there is no dirt or other foreign objects on the sealing surface of the disconnected pipe. Clean it away if necessary.
        Fig 6: Pushing In & Pull On Connector To Release It & Pull Connector Out Of Pipe Carefully
        G02974093Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      6. Do not damage the disconnected pipe and connector, and prevent intrusion of foreign objects by covering them with a plastic bag.
        Fig 7: Covering Connector With Plastic Bag
        G02974094Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Observe the following precautions when connecting the fuel tube connectors (Quick Type A):
      1. Check that there is no damage or foreign objects in the connected part of the pipe.
      2. Match the axis of the connector with the axis of the pipe, and push into the connector until the connector makes a "click" sound. If the connection is tight, apply a small amount of fresh engine oil to the tip of the pipe.
        Fig 8: Connecting Fuel Tube Connectors
        G02974095Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. After finishing the connection, check if the pipe and the connector are securely connected by pulling on them.
      4. Check for fuel leaks.
        Fig 9: Checking Pipe & Connector Are Securely Connected
        G02974096Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Observe the following precautions when disconnecting the fuel tube connector (Quick type B):
      1. Check that there is no dirt or other foreign objects around the connector before disconnecting the fuel pump tube.
      2. Disengage the 2 claws of the connector retainer. Push down on the connector and disconnect it from the pipe.

        HINT:

        Be sure to disconnect it by hand.

        Fig 10: Disengaging Claws Of Connector Retainer
        G02974097Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. If the connector and pipe are stuck, pinch the fuel pipe by hand and push or pull on the connector to disconnect it.
      4. Check that there is no dirt or other foreign objects on the sealing surface of the disconnected pipe.
        Fig 11: Disconnecting Fuel Pipe By Hand, Pushing Or Pulling On Connector
        G02974098Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Do no damage the connector and pipe, and prevent intrusion of foreign objects by covering them with a plastic bag.
        Fig 12: Covering Connector & Pipe With Plastic Bag
        G02974099Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. Observe the following precautions when disconnecting the fuel tube connector (Quick type B):
      1. Match the axis of the connector with the axis of the pipe. Push into the connector and push up on the retainer.

        HINT:

        If it is hard to make the connection, apply a small amount of engine oil to the tip of the pipe.

      2. After finishing the connection, pull on the connector and pipe and make sure that they are securely connected.
      3. Check for fuel leaks.
        Fig 13: Connecting Fuel Tube Connector (Quick Type B)
        G02974100Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    8. Observe the following precautions when handling a nylon tube:
      CAUTION:
      • Do not twist the connection part of the nylon tube and the quick connector when connecting them.
      • Do not bend or twist the nylon tube.
      • Do not remove the EPDM protector on the outside of the nylon tube.
      • Do not close the piping by bending the nylon tube.
  5. CHECK FOR FUEL LEAKS 
    1. Check that there are no fuel leaks after doing maintenance on the fuel system (see ON-VEHICLE INSPECTION ).
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