To prevent the occurrence of abnormal lowering of output and engine stall due to increased number of misfired cylinders by controlling the ignition timing and fuel injection in all-cylinder operating mode regardless of the operating condition in the case of detecting abnormality of a pulser signal or a crank angle signal.

If a pulser signal of #2 of a 6-cylinder engine is omitted, the count number stated by a pulser signal of #1 is not ended with #1, so that the count number is detected by a pulser signal of #3. Accordingly, when the count of #3 is ended, the count number is double normal value and exceeds a preset fail determination value. Thus, pulser signal fail of j2 is detected. At a point of time the pulser signal fail is detected, the control mode for ignition timing and fuel injection at each cylinder by map operation is switched to fixed ignition timing control synchronized with a pulser signal and all-cylinder simultaneous injection control mode synchronized with as specified cylinder.