Controller for internal combustion engine

Abstract

A controller for controlling the combustion timing of an internal combustion engine and a method for controlling the ignition timing of an internal combustion engine in which variations in combustion timing as detected from the pressure in the combustion chamber of the engine and the intensity of knocking are simultaneously detected and the ignition timing corrected to provide optimum combustion efficiency at all times. From the sensed pressure in the combustion chamber, the crank angle at which the maximum pressure occurs is determined. If the crank angle thus determined exceeds a first reference value, a first ignition time correcting signal is generated. If the knocking intensity exceeds a second reference value, a second ignition timing correcting signal is generated. The output signal utilized to correct the ignition timing is produced by selecting one of the two ignition timing correcting signals thus generated, wherein the second ignition timing correcting signal has priority over the first ignition timing correcting signal.