Patent US 4,201,159

In a method and apparatus for controlling a combustion engine, a digital computer is adapted to calculate first and second values corresponding to optimal settings of fuel injectors and spark plugs in a time sequence by detecting changes of the amount of air flowing into the engine and the rotation speed of the engine. The computer is programmed to calculate the first and second values from first and second functions describing desired relationships among each setting of the fuel injectors and the spark plugs, the amount of air flowing into the engine and the rotation speed of the engine. An electronic control circuit in the form of a timer is coupled with the digital computer for generating an electric control signal with a predetermined period of time in response to the setting of the spark plugs and applying the control signal to the computer to halt the calculation of the first value during the predetermined period of time even if the computer is conditioned to calculate the first value, the remaining calculation of the first value being subsequently performed after lapse of the predetermined period of time.