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Fuel System: Precaution

  1. PRECAUTION 
    1. Before working on 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.
  2. DISCHARGE FUEL SYSTEM PRESSURE 
    CAUTION:
    • Do not disconnect any part of the fuel system pressure until you have discharged the fuel system pressure.
    • Even after discharging the fuel pressure, place a shop rag over fitting as you separate them to reduce risk of fuel spray on yourself or in the engine compartment.
    1. Remove the circuit opening relay from the instrument panel junction block.
    2. Start the engine. After the engine stopped, turn the ignition switch OFF.

      HINT: 

      Possibly DTC P0171 (system too lean) will be set

    3. Check that the engine does not start.
    4. Remove the fuel tank cap, and let the air out of the fuel tank.
    5. Disconnect the negative (-) battery cable.
    6. Reinstall the circuit opening relay.
      Fig 1: Identifying C/OPN Relay
      G00759288Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. FUEL SYSTEM 
    1. When disconnecting the high fuel pressure line, a large amount of gasoline will spill out, so observe these procedures.
      1. Discharge the pressure in the fuel system.
      2. Disconnect the fuel pump tube.

        (See REMOVAL & INSTALLATION AND DISASSEMBLY & REASSEMBLY  )

      3. Drain the fuel that remains inside the fuel pump tube.
      4. In order to prevent the disconnected fuel pump tube from being damaged and foreign objects from being introduced, cover with a vinyl or plastic bag.
      5. Place a tray under the vehicle or point of disconnection to catch any fuel that may spill.
      Fig 2: Covering Fual Line Connector
      G00759289Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Take the following precautions when removing and installing the fuel injectors.
      NOTE: Never reuse the O-ring.
      1. When installing a new O-ring on the injector, be careful not to damage it.
      2. Coat the new O-ring with grease or gasoline before installing. Never use engine oil, gear oil or brake oil.
      Fig 3: Installing Method Of Injector O-Ring
      G00759290Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Install the injector to the delivery pipe and cylinder head as shown in the illustration. Before installing the injector, be sure to apply grease or gasoline on the place where the delivery pipe contacts the O-ring of the injector.
      Fig 4: Installing Injector To Delivery Pipe And Cylinder Head
      G00759291Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Take these precautions when disconnecting the fuel tube connectors.
      1. Disconnect the fuel pipe clamp from the connector.
      2. Check on the pipe and around the connector for dirt or mud before disconnecting them and remove the dirt if necessary.
        Fig 5: Identifying Fuel Pipe Clamp
        G00759292Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Disconnect the connector from the hose while pinching part A with your fingers as shown in the illustration.
        Fig 6: Disconnecting Connector From Hose
        G00759293Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. If the connector and pipe are stuck, pinch the fuel pipe with your fingers, push and pull the connector to release and disconnect and pull it out. Do not use any tools.
      5. If there is dirt or any other substance on the sealing surface that might interfere with the seal, clean the area thoroughly before assembling.
        Fig 7: Pinching Fuel Pipe
        G00759294Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      6. Prevent damage and dirt on the disconnected pipe and connector from damage and dirt by covering them with a vinyl or plastic bag.
      Fig 8: Covering Pipe Connector
      G00759295Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Take these precautions when connecting the fuel tube connectors.
      1. Check the connected part of the pipe for damage or foreign objects.
      2. Align the axis of the connector with the axis of the pipe, and push into the connector until the connector makes a "click" sound. In case that the connection is tight, apply a little amount of fresh engine oil on the tip of the pipe.
        Fig 9: Checking Pipe Connection
        G00759296Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. After finishing the connection, check if the pipe and connector are securely connected by pulling on them.
      4. Install the fuel pipe clamp to the connector.
      5. Check for fuel leaks.
      Fig 10: Checking Fuel Leaks
      G00759297Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. CHECK FOR FUEL LEAKS 
    1. Check that there are no fuel leaks after doing maintenance anywhere on the fuel system. (See ON-VEHICLE INSPECTION  )