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Engine Control Module (ECM) - Learning Ability

The ECM has a learning ability that allows it to make corrections for minor variations in the fuel system to improve drive ability and engine idle. If the battery is disconnected, or the ECM is replaced, the ECM must go through a learning process. Until the ECM has gone through this learning process, a change may be noted in the drive ability, or idle of the vehicle. To allow the ECM to relearn, the following steps must be performed:
^ Start the vehicle and run the engine until normal operating temperature is obtained.
^ Drive the vehicle at part throttle, with moderate acceleration and idle conditions until normal performance returns.
^ Park the vehicle and engage the parking brake with engine running.
^ Place the transaxle in Drive.
^ Allow the vehicle to idle for about two minutes, until engine idle stabilizes. Make sure engine is at operating temperature.