| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress discharge spark blowing-off (a phenomenon that the discharge spark of an ignition plug cannot be maintained longer), when air flow intensification is performed during execution of an EGR control. <P>SOLUTION: The air flow intensification intensifying the air flow is performed during the execution of the EGR control in which EGR gas is recirculated in an intake pipe 12, so that the discharge spark of the ignition plug 25 is expanded. Further, a blowing-off suppression control is executed. In the blowing-off suppression control, it is determined whether the blowing-off of the discharge spark will occur during the execution of the EGR control, based on air flow intensity and ignition timing of the spark plug 25. If it is determined that the blowing-off of the discharge spark will occur, a discharge current of the spark plug 25 is increased to elongate a time until the discharge current drops below a discharge-sustaining current (a time until discharge voltage drops below discharge-sustaining voltage) so that the blowing-off of the discharge spark is suppressed. A period where the discharge spark is expanded by the air flow intensification is elongated to effectively improve ignition performance of air-fuel mixture. <P>COPYRIGHT: (C)2013,JPO&INPIT |
