Daewoo MUSSO Service Manual page 790

1G1-8 M162 ENGINE INTAKE & EXHAUST
Function Description
A pneumatically actuated resonance flap (5) is located on the
intake manifold, and will be opened and closed by load, which
operates resonance flap according to engine and controlled
by ECU and rpm.
1. Resonance flap closed (at idle/partial load : less than
3,800/rpm)
The switch valve (7) will be adjusted by ECU and resonance
falp will be colosed. By increasing air flow passage through
dividing intaking air flow toward both air collection housing
(8). This leads to a signficant increase in the torque in the
lower speed range.
2. Resonance flap open (at full load : over 3,800/rpm)
The switch valve (7) will not be adjusted by ECU and
resonance falp (5) will be open. The colllected air in the air
collection housing (8) will not be divided and intaking air
passage will be shorten.