PURPOSE: To relatively perform injection control and ignition timing control and prevent deterioration of feeling during idling operation by providing a specified injection compensation quantity setting means and an ignition timing compensation quantity setting means respectively, in a device which makes fuel injection control and ignition timing control at the same time.

CONSTITUTION: When an engine is under an idling condition, in the case when rotational variation difference of cylinders is out of an allowable rotational limitation, an injection compensation quantity in each cylinder is compensated in respouse to the ratio of sum of an absolute value of the rotational variation difference to the rotational variation difference of the cylinder and when the injection compensation quantity of the cylinder exceeds the allowable upper limit value, the injection compensation quantity in the cylinder is decreased by a set quantity, and also the injection compensation quantities of the other cylinder are distributingly increased by the amount of the decreased quantity. An injection compensation quantity setting means M5 is provided, and the basic injection quantity is compensated by the injection compensating quantity so that a fuel supply means M7 is controlled. In the case when the injection compensation quantity of the appropriate cylinder exceeds the allowable upper limitation value under an idling condition, an ignition timing compensation quantity of the appropriate cylinder is advanced by a specified angle. An ignition timing conpensation quantity sching means M8 is provided, and basic ignition timing is compensated by the ignition timing compensation quantity so that an ignition means M10 is controlled.