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Intake Air Control System: Inspection

  1. INSPECT INTAKE AIR CONTROL VALVE ACTUATOR 
    1. Attach a vacuum pump to the actuator. Apply a vacuum of 39.9 kPa (300 mmHg, 11.8 in.Hg) and check that the diaphragm's lever moves.
    2. Leave the diaphragm as is for 1 minute. Check that the vacuum pump's vacuum reading has not changed.

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

      Fig 1: Inspecting Intake Air Control Valve Actuator
      G02958831Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. INSPECT VACUUM CONTROL VALVE SET 
    1. Attach a vacuum pump to the port A. While holding the port B closed, apply a vacuum of 66.7 kPa (500 mmHg, 20 in.Hg) and leave the diaphragm as is for 1 minute. Check that the vacuum pump's vacuum reading has not changed.
      Fig 2: Attaching Vacuum Pump To Port A
      G02958832Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check that there is no ventilation when pressure is applied to port B, and that there is ventilation when a vacuum is applied to port B.

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

      Fig 3: Checking No Ventilation When Pressure Is Applied To Port B
      G02958833Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. INSPECT ACIS VSV 
    1. Measure the resistance of the VSV.

      Standard: 

      ACIS VSV RESISTANCE

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

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

      Fig 4: Measuring Resistance Of VSV
      G02958834Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check operation of the VSV.
      1. Check that air flows from port E to the filter.

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

        Fig 5: Checking VSV Operation
        G02958835Courtesy 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.

        Fig 6: Checking Air Flows From Port E To Port F
        G02958836Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002