PURPOSE: To suppress the reduction of the engine output to the utmost by setting the control pattern which is most desirable and available in the control of the rest output varying means on the basis of the preference order when troubles are detected in a part of the output varying means.
CONSTITUTION: One surge tank 10 and the other surge tank 11 are connected through the first short communication passage 20 and the second long communication passage 21, and when the first communication passage 20 is opened (S valve 22 is opened), the dynamic effect of intake due to resonance is obtained, and when the second communication passage 21 is opened (A valve 23 is opened), the dynamic effect of the intake due to inertia is obtained. When a part of an output varying means 22 or 23 is broken, the pattern which is most desirable and available under a trouble state is set on the basis of the preference order, and the control for the rest normal output varying means is carried out, and the extreme reduction of the output can be prevented.
KAWAGUCHI HIROYUKI
TOMII TATSUYA
TANIGUCHI MASAAKI
