ENGINE CONTROLLER, AND ABNORMALITY DIAGNOSTIC DEVICE THEREFOR

摘要

PROBLEM TO BE SOLVED: To diagnose abnormality in change control of a fuel injection situation for an engine. SOLUTION: An sensor 18 for detecting an oxygen concentration in exhaust is provided in an exhaust passage 20 of the engine to determine the abnormality in change control of a combustion condition based on change of the oxygen concentration detected by the sensor 18 when the change control of the combustion condition by a combustion control means 35 brings increasing change of HC(hydrocarbon) concentration, and a reaction promoting means for promoting reaction between oxygen and HC in the exhaust is provided to change the oxygen concentration toward an increasing direction by promoting the reaction.