ERROR DETECTION DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

An object of the present invention is to enable accurate detection of abnormality in a fuel property sensor that is used to determine properties of a fuel employed in an internal combustion engine whose operation is controlled in accordance with the properties of the employed fuel, or more particularly, enable accurate detection on whether the fuel property sensor is stuck. In order to achieve the above object, the present invention provides an abnormality detection device in which the fuel property sensor is not disposed in a primary flow path of a fuel flow path connecting a fuel pump to an injector, but is disposed in a branch flow path which is such that there is a time where the fuel in the branch flow path drops out therefrom between one start of the internal combustion engine and the next start. An output value of the fuel property sensor generated when the fuel is flowing through the branch flow path is acquired as a first sensor output value. An output value of the fuel property sensor generated when the fuel in the branch flow path drops out therefrom is acquired as a second sensor output value. The first sensor output value and the second sensor output value are used as judgment data to judge whether the fuel property sensor is abnormal.