Steuerungsvorrichtung und Steuerungsverfahren für einen Verbrennungsmotor

摘要

A control device for an internal combustion engine includes: an abnormality determination portion determining the presence of an abnormality in a fuel system, such as an injector, by comparing an air-fuel ratio detected by an A/F sensor and a learning value of the air-fuel ratio with a preset abnormality determination value; an alcohol concentration estimating portion estimating the alcohol concentration in fuel based on the air-fuel ratio detected by the A/F sensor and the learning value; and an abnormality determination value changing portion changing the abnormality determination value depending on the alcohol concentration estimated by the alcohol concentration estimating portion.