2003 Lexus LS 430FACTORY OEM SERVICE PROCEDURE

Intake Air Control System (2UZ-FE): Inspection

WARNING: This page is about a different car, the 2005 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT INTAKE AIR CONTROL VALVE 
    1. With 39.9 kPa (300 mmHg, 11.8 in.Hg) of vacuum applied to the actuator, check that the actuator rod moves.
    2. One minute after applying the vacuum in step (a), check that the actuator rod does not return.

      If operation is not as specified, replace the intake manifold.

    Fig 1: Inspecting Intake Air Control Valve
    G02578361Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. INSPECT VACUUM SWITCHING VALVE ASSY FOR IAC VALVE 
    1. Using an ohmmeter, check that there is continuity between each terminal.

      Resistance: 33 to 39 ohms at 20°C (68°F) 

      If there is no continuity, replace the VSV.

      Fig 2: Checking Continuity Between Terminal Using Ohmmeter
      G02578362Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Using an ohmmeter, check that there is no continuity between each terminal and the body.

      Resistance: 10 k-ohm or higher 

      If there is continuity, replace the VSV.

      Fig 3: Checking Continuity Between Terminal and Body Using Ohmmeter
      G02578363Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Check that air flows from port E to the filter.
      Fig 4: Checking Air Flows From Port E To Filter
      G02578364Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Apply battery voltage across the terminals.
    5. Check that air flows from port E to port F.

      If operation is not as specified, replace the VSV.

    Fig 5: Applying Battery Voltage Across Terminals
    G02578365Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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