2002 Lexus SC 430FACTORY OEM SERVICE PROCEDURE

Intake Air Control System: Inspection

WARNING: This page is about a different car, the 2004 Lexus LS 430. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT INTAKE AIR CONTROL VALVE ACTUATOR 
    Fig 1: Inspecting Intake Air Control Valve Actuator
    G01051960Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. (a) 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.

  2. INSPECT VACUUM TANK 
    Fig 2: Inspecting Vacuum Tank
    G01051961Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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.

  3. INSPECT VACUUM SWITCHING VALVE ASSY FOR IAC VALVE 
    1. Measure the VSV resistance.

      Standard: 

      Fig 3: VSV Resistance Chart
      G01051963Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

      Fig 4: Measuring VSV Resistance
      G01051962Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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 5: Checking Air Flows From Port E To Filter
        G01051964Courtesy 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 6: Checking Air Flows From Port E To Filter
      G01051965Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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