Resonance Intake System Operating Points

Idling speed up to 2550 ± 100 rpm :
Intake line resonance flap (99/2) and intake manifold resonance flap (99/4) closed.
The vibrations of the air column extend as far as the pressure-regulating flap.







From 2550 ± 100 rpm up to 3350 ± 100 rpm:
Intake line resonance flap (99/2) open and intake manifold resonance flap (99/4) closed.
The vibrations of the air column extend up to the intake line resonance flap.







From 3350 ± 100 rpm:
Intake line resonance flap (99/2) and intake manifold resonance flap (99/4) open.
The vibrations of the air column extend up to the stop of the resonance pipes.