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Home >> Buick >> 2005 >> Century Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Introduction >> Repair Instructions >> Idle Air Control (IAC) Valve Replacement >> Installation Procedure
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Installation Procedure

NOTE: The IAC valve may be damaged if installed with the cone (pintle) extended more than 28 mm (1-1/8 in). Measure the distance that the valve is extended before installing a new valve. The distance from the idle air control valve motor housing to the end of the idle air control valve pintle should be less than 28 mm (1-1/8 in). Manually compress the pintle until the extension is less than 28 mm (1-1/8 in).
    Fig 1: IAC Valve O-Ring
    GM185626Courtesy of GENERAL MOTORS CORP.
  1. Install the new IAC valve O-ring.
  2. Fig 2: View Of IAC Valve
    GM185583Courtesy of GENERAL MOTORS CORP.
  3. Install the IAC valve.
  4. Fig 3: Installing IAC Valve Screws
    GM185614Courtesy of GENERAL MOTORS CORP.
    NOTE: Refer to Fastener Notice in Cautions and Notices.
  5. Install the IAC valve screws.

    Tighten:  Tighten the screws to 3 N.m (27 lb in).

  6. Fig 4: View Of IAC Valve Electrical Connector
    GM69056Courtesy of GENERAL MOTORS CORP.
  7. Connect the IAC valve electrical connector.
  8. The powertrain control module (PCM) will reset the IAC valve whenever the ignition is turned ON, then OFF. Turn the ignition ON, then OFF.
  9. Start the engine. Allow the engine to reach operating temperature. Verify proper operation.