| 摘要 |
The purpose of the present invention is to accurately detect an abnormality in the sensitivity of a cylinder pressure sensor in a wide operating range without using other sensor outputs or the like. An ECU (50) acquires, on the basis of only the output of a cylinder pressure sensor (44), a first parameter that is affected by the output sensitivity of the sensor, and a second parameter that is not affected by said output sensitivity. More specifically, the ECU acquires the heat generation amount (PV?) as the first parameter, and acquires the illustrated torque ratio (A2/A1) as the second parameter. The ECU calculates the determination coefficient (a), which is the ratio between the first and second parameters, and determines that the output sensitivity of the cylinder pressure sensor (44) is abnormal if the determination coefficient (a) is outside a permissible range. Thus, an abnormality in the sensitivity of the cylinder pressure sensor (44) can be detected easily in a wide operating range, without using other sensor outputs or the like in an auxiliary manner and without preparing a multitude of pieces of data or the like in advance. |
