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  5. A. Idle Relearn

A. Idle Relearn

If the ECU has been removed, or battery power has been disconnected, the first start will require an idle relearn
including IAC reset. The ECU will do this automatically on first start once the engine RPM exceeds 2,500rpm for
greater than 4 seconds.

To start the process manually:

  • Start the engine in Park/Neutral. Rev the engine to above 2,500rpm and hold for 10-15 seconds.
  • Slowly reduce throttle back to idle.
  • The ECU should now begin to learn the idle position (you will hear the sucking sound through the throttle body change as the Idle Air Control Motor changes position).

To complete the idle relearn:

  • Bring the engine to normal temperature, have the accessories off.
  • Leave idling for 2 minutes in Park/Neutral to learn.
  • With the vehicle securely held on the brakes or wheel chocks, change into Drive.
  • Leave idling for 2 minutes in Drive to learn.
  • Turn the Air-conditioning on full if fitted.
  • Leave idling for 2 minutes to learn with A/C ON in Drive.
  • Return the vehicle to Park/Neutral with A/C still on.
  • Leave idling for 2 minutes in Park/Neutral to learn.
  • Leave idling for 2 minutes to learn with A/C ON in Park/Neutral.
  • (Obviously a Manual Transmission vehicle learns only in Neutral).