Air Injection System: Operation

The pulse air injection system routes air from the filtered side of the air cleaner through a hose to the air control valve. When opened by the air switch solenoid, the air control valve allows air through the air injection check valve. The air enters the exhaust system (upstream or downstream) from the check valve. Air is injected either into the front exhaust manifold (upstream), or into the catalytic converter (downstream) depending upon engine operating conditions. The switching of upstream or downstream air into the exhaust system is controlled by the vehicles MCU.