| 摘要 |
PURPOSE:To set ignition timing always properly by advancing or retarding reference ignition timing if tide ignition timing to be computed enters a predetermined range around the reference ignition timing as the retard from fundamental ignition timing or the advance from lower-limit ignition timing increases. CONSTITUTION:An electronic control unit 20 controls the injector 12 and the ignitor 14 of an internal combustion engine 2 in accordance with detection signals of sensors for detecting the operating conditions of the internal combustion engine 2, e.g. an airflow meter 8, a knock sensor 10 and a turning angle sensor 18. In this case, the electronic control unit 20 sets reference ignition timing between fundamental and lower-limit ignition timing. If the ignition timing to be computed enters a predetermined range around the reference ignition timing as the retard from the fundamental ignition timing or the advance from the lower-limit ignition timing increases, the reference ignition timing is advanced or retarded in setting the ignition timing. Therefore, the ignition timing can be set without greatly deviating from either the fundamental, lower- limit or reference ignition timing which is to be corrected, prior to sudden change of load. |
