Learning control system for controlling an automotive engine

A system for updating data in an apparatus for controlling air-fuel ratio in an automotive engine by the updated data, the system comprising:

• a look-up table for storing data with respect to at least one operating condition of the engine;
• and
• first means for detecting an operating condition of the engine and for producing a feedback signal dependent on the latter operating condition;
• the apparatus comprising means for controlling the air-fuel ratio dependent on said feedback signal and on the currently prevailing of the data in the look-up table;
• said system further comprising:
• second means for determining that engine operation is in steady state by determining that two variables of engine operation stay in one of divisions of a matrix for a predetermined period, the matrix being formed by the two variables of engine operation, said second means for producing an output signal when the steady state is so determined;
• third means for detecting said output signal and for producing a first updating signal when said output signal did not occur before, and respectively for producing a second updating signal in response to occurrence of the output signal after a first occurrence of said output signal;
• fourth means responsive to the first updating signal for completely updating the data in the table stored with respect to said at least one operating condition of the engine with a value dependent on an arithmetical average of the feedback signal;
• fifth means responsive to the second updating signal for incrementing and respectively decrementing the data stored in the table with a minimum value capable of storing in said table;
• and
• sixth means for continuing the operation of the fifth means until the feedback signal reaches a desired value.