| 摘要 |
PURPOSE:To prevent black smoke, NOx or noise from increasing, by compensating the timing of fuel injection so that it becomes a required ignition timing when an ignition sensor is deteriorated. CONSTITUTION:A microcoputer 3 determines that an ignition timing sensor 4 deteriorates when a value obtained by subtraciting a required ignition timing which is calcullated in accordance with the opening degree of an accelerator and the rotational speed of an engine, from an actual ignition timing detected in accordance with the outptu of the ignition timing sensor 4, exceeds a predetermined time (0). At this time a value obtained by subtracting the difference between the calculated required ignition timing and the real ignition timing, from a reauired ignition time is set to a new required ignition timing while the actual ignition timing is set to the required ignition timing, and thereafter, they are compensated. Then, a basic timer duty of a timing control valve 22 which realize the timing of fuel injection corresponding to the required ignition timing after compensation is calcualted. With this arrangement even if a decrease in the output of the ignition timing sensor 3 occurs due to deterioration of the ignition timing sensor 4, etc., it is possible to approximately control the ignition timing. |
