| 摘要 |
PURPOSE:To compensate a decrease in the amount of fuel injection due to blockage of a nozzle section to avoid lowering the performance of an engine up fully opening operation, in an electronically controlled fuel injection device in a spark ignition type internal-combustion engine, by injecting fuel from two injection valves in the identical time period. CONSTITUTION:Two fuel injection valves 3, 4 positioned upstream of an intake- air throttle valve 2 are operated under feed-back control for the injection amount of fuel by means of a control circuit 7 in accordance with a signal from an oxygen sensor 21 disposed in an exhaust passage 6 so that a mixture for the stoichometric air-fuel ratio of the engine is produced. Normally, drive control is made such that fuel is injected from both fuel injection valves 3, 4, alternately. When the oxygen sensor 21 informs such an indication that the air-fuel ratio is successively deviated for a predetermined time period toward the lean side of mixture, a judging circuit and a compensation comuting circuit controls two injection valves 3, 4 so that fuel is injected from both valves 3, 4 in the identical time period, and the injection cyclce numbers thereof are increased. With this arrangement, even if the injection valves 3, 4 are blocked, it is possible to avoid lacks of supply fuel upon high output power operation, etc. |
