| 摘要 |
PURPOSE:To prevent degradation of the engine performance at the time when operation of a sensor for detecting the quantity of intake air becomes abnormal, by setting the basic injection quantity of fuel at a prescribed value corresponding to the engine speed when operation of the above sensor becomes abnormal in a control apparatus in which the basic injection quantity of fuel is calculated from the quantity of intake air and the engine speed. CONSTITUTION:In operation of an engine, a signal representing the quantity Q of intake air detected by an air-flow meter 11 and a signal representing the engine seed N detected by a crank-angle sensor 13 are picked up from an input circuit 12 to a judging circuit 14 at predetermined time intervals. In the judging circuit 14, the quantity Q of intake air is compared with a reference value Q0. In case of Q>Q0, the air-flow meter 11 is judged to be normal. In case of Q<Q0, on the other hand, it is judged to be abnormal. Here, if the air-flow meter 11 is judged to abnormal, comparison is made between ''fuel cut'' engine speed Nc and the actual engine speed N in an auxiliary arithmetic circuit 16, and in case of N>Nc, ''fuel cut'' is effected. On the other hand, in case of Nc> N>No (No is the cranking speed), the final injection quantity of fuel is determined by furnishing a prescribed basic injection quantity Tpo to an arithmetic circut 15 and correcting the injection quantity Tpo appropriately. |
