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Intake Air Control System: Inspection

  1. INSPECT INTAKE AIR CONTROL VALVE ACTUATOR 
    1. Connect the MITYVAC (hand-held vacuum pump) to the actuator.
    2. Apply a vacuum of 39.9 kPa (300 mmHg, 11.8 in.Hg) to the actuator and check that the actuator rod moves.
    3. One minute after applying the vacuum, check that the rod's position is the same as in step (a).

    If the result is not as specified, replace the IAC valve actuator.

    Fig 1: Inspect Intake Air Control Valve Actuator
    G02999226Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. INSPECT VACUUM TANK 
    1. Connect the MITYVAC (hand-held vacuum pump) to port A.
    2. Apply a vacuum of 66.7 kPa (500 mmHg, 20 in.Hg) to the vacuum tank.
    3. One minute after applying the vacuum, check that the pressure does not change.

    If the result is not as specified, replace the vacuum control valve set.

    Fig 2: Inspecting Vacuum Tank
    G02999227Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. INSPECT VACUUM SWITCHING VALVE ASSY FOR IAC VALVE 
    1. Measure the VSV resistance.
      Fig 3: Measuring VSV Resistance
      G02999228Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      VACUUM SWITCHING VALVE ASSY FOR IAC VALVE

      Tester Connection Specified Condition
      1 - 2 33 to 39 Ω at 20°C (68°F)
      1 - Body ground, 2 - Body ground 10 kΩ or higher

      If the resistance is not as specified, replace the VSV assy.

    2. Check the VSV operation.
      1. Check that air flows from port E to the filter.

        If the result is not as specified, replace the VSV assy.

        Fig 4: Checking Air Flows From Port E To Filter
        G02999229Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Apply battery positive voltage across the terminals.
      3. Check that air flows from port E to port F.

      If the result is not as specified, replace the VSV assy.

      Fig 5: Checking Air Flows From Port E To Port F
      G02999230Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002