PURPOSE: To perform fine control/diagnosis with high responce, in an electronic controller for car engine by predicting the operating stage of engine accurately and reflecting it onto control thereby predicting future phenomena such as engine stall.

CONSTITUTION: An electronic engine controller is provided with various sensors for detecting the operating state of engine or auxiliary machines, operating means 21 for performing various operations required for control or display, variour actuators functionable with correspondence to the results from the operating means 21 and display means 22. An actual operation pattern measuring means 23 will sample/store signals from sensor group 20 with predetermined period. State pattern memory means 24 is storing operating pattern data corresponding with specific engine state. Furhtermore, an engine state predicting means 25 will compare between the pattern data from measuring means 23 and memory means 24 to predict whether engine is in specific state on the basis whether they are similar patterns or not.