California Models

Air Suction System Schematic:

Air Suction Operations Chart:

The air suction (AS) system is used to direct air into the exhaust ports to extend the combustion of unburned hydrocarbons (HC) and carbon monoxide (CO) in the exhaust system. This air is also used as the oxygen source for the catalytic converter. Air flow is controlled by a valve assembly that includes a vacuum operated shut-off valve and a reed valve. During normal operation, the shut-off valve is held open by manifold vacuum. Vacuum created by exhaust pulses opens the reed valve and air is drawn into the exhaust stream. The vacuum transmitter valve (VTV) in the vacuum control line, delays application of the shut-off valve.