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Minimum Air Rate

NOTE: Verify correct controlled idle speed. Perform idle air control check before adjusting minimum air rate. Refer to the CCC TBI TESTS W/CODES article in the COMPUTER ENG CONTROL section.
  1. Remove air cleaner and gasket. With Idle Air Control (IAC) valve connected, ground terminal "A" to "B" at ALDL connector. refer to the CCC TBI TESTS W/CODES article in the COMPUTER ENG CONTROL section.
  2. Turn ignition on, DO NOT start engine. Wait approximately 30 seconds for IAC valve pintle to extend and seat in throttle body.
  3. With ignition on, disconnect IAC valve electrical connector. Remove ground at ALDL connector. Using an awl, remove plug for minimum idle speed adjustment by piercing, then applying leverage.
  4. Install a tachometer and start engine. Allow engine to reach operating temperature. Adjust idle screw to specification with vehicle in Neutral. Turn ignition off. Reconnect IAC valve electrical connector. Install air cleaner and gasket.
  5. This procedure will set a code 35. Erase code by disconnecting electrical power to ECM for 30 seconds.
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