Adaptation Values

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To maintain an ideal air/fuel ratio, engine control module is capable of adapting to various environmental conditions encountered while the vehicle is in operation (i.e. changes in altitude, humidity, ambient temperature, fuel quality, etc.). Adaptation system can only make slight corrections and cannot compensate for large changes which may be encountered as a result of incorrect airflow or incorrect fuel supply to the engine.

Within areas of adjustable adaption, engine control module modifies injection rate during idle and low load mid range engine speeds (additive adaptation) and during operation under a normal to higher load when at higher engine speeds (multiplicative adaptation). These values are displayed in DIAGNOSIS REQUESTS section of DIS software and is a helpful diagnostic tool that shows how system is trying to compensate for a less than ideal initial air/fuel ratio. See DIAGNOSIS REQUESTS table.

NOTE: If adaptation value is greater than 0.0 ms, engine control module is trying to enrichen mixture. If adaptation value is less then 0.0 ms, engine control module is trying to lean mixture.

DIAGNOSIS REQUESTS

Diagnostic Request Status/Additive Mixture Adaptation (Idle)	Explanation
The O2 sensor indicates a LEAN condition.	The engine control module tries to RICHEN the mixture. If the value is less than -0.2 ms there is an air restriction or too much fuel is being supplied to the system. If the value is greater than 0.2 ms there is an unmetered air leak or not enough fuel being supplied to the system.
The O2 sensor indicates a RICH condition.	The engine control module tries to LEAN out the mixture. If the value is greater than 8% there is an unmetered air leak or not enough fuel being supplied to the system.