•  The PCM energizes the variable intake air solenoid valve when the engine speed is less than 4,600 rpm (LF)/4,400 rpm (L5), closing the variable intake-air shutter valve to enhance the inertia charging effect at the low engine speed range.

•  The PCM blocks energization to the variable intake air solenoid valve when the engine speed is 4,600 rpm (LF)/4,400 rpm (L5) or more, opening the variable intake shutter valve to enhance the inertia charging effect at the high engine speed range.