| 摘要 |
When the operating state of an engine consisting of the rotating speed (Ne) and the torque (Te) belongs to the resonance region in the post-stage including a damper connected with the crankshaft of the engine, a subtraction sine wave for removing the influence by resonance is calculated (S310), and then misfire is judged (S320, S330) depending on whether the variation ?F in rotating speed F(N30) obtained by subtracting the calculated subtraction sine wave from a variation in 30° rotating speed (N30) which is the rotating speed every time when the crankshaft rotates by 30° is smaller than a threshold Fref or not. Consequently, misfire can be judged more certainly and precisely even when the operating state belongs to the resonance region. |
