GM Service Manual Online
For 1990-2009 cars only

Whenever the throttle body and/or the engine control module (ECM) are replaced, the following idle learn procedure must be performed:

  1. Turn the ignition ON for 5 seconds.
  2. Initialize the idle speed control (ISC) using a scan tool.
  3. Initialize the ECM using the scan tool. This is for a replacement ECM only.
  4. Turn the ignition OFF for 10 seconds.
  5. Turn the scan tool OFF.
  6. Turn the ignition ON for 10 seconds.
  7. Turn the ignition OFF for 10 seconds.
  8. Start the engine in park/neutral.
  9. Allow the engine to run until the engine coolant is above 85°C (185°F).
  10. Turn the A/C ON.
  11. If the vehicle is equipped with an automatic transaxle, apply the parking brake. While pressing the brake pedal, place the transaxle in drive (D).
  12. Turn the A/C OFF.
  13. If the vehicle is equipped with an automatic transaxle, apply the parking brake. While pressing the brake pedal, place the transaxle in drive (D).
  14. Turn the ignition OFF. The idle learn procedure is complete.