| 摘要 |
<P>PROBLEM TO BE SOLVED: To accurately determine misfire in an internal combustion engine in the process of operating the internal combustion engine to warm up the catalyst of an exhaust emission control device for purifying exhaust gas from the internal combustion engine. <P>SOLUTION: When a rotating fluctuation difference Nxd360 as a difference from a rotating fluctuation Nxd before crank angle 360° CA exceeds a determination value A1 and a rotating fluctuation difference Nxd 720 as a difference from a rotating fluctuation Nxd before a crank angle 720° CA exceeds a determination value B1 (S150, S160), if determination (S200) by rotating fluctuation difference ratios Nja2, Nja3, Nja4 with the rotating fluctuation difference Nxd 360 and determination (210) by rotating fluctuation difference ratios Njb2, Njb3, Njb4 with the rotating fluctuation difference Nxd 720 are both established, misfire is determined. Thus, the misfire can be more adequately and accurately determined in the process of warming up the catalyst of the exhaust emission control device with an engine ignition timing being greatly delayed. <P>COPYRIGHT: (C)2007,JPO&INPIT |
