Air Injection: Description and Operation

AIR System Operation:

AIR System:

PURPOSE
The Air Injection Reaction (AIR) system helps reduce Hydrocarbons (HC), Carbon Monoxide (CO) and Oxides of Nitrogen (NOx) exhaust emissions. The AIR system heats the catalytic converter quickly on engine start up so conversion of exhaust gases can occur sooner.

OPERATION OF SYSTEM COMPONENTS
The system includes:

AIR pump
The AIR pump is located in the left front of the underhood compartment and supplies the air (oxygen) to the Air system. This electric air pump pressurizes air from the engine air cleaner and pumps it through the check valve and into the exhaust manifold.

The AIR pump is controlled by the PCM. Battery voltage to the AIR pump is controlled by the AIR pump relay. An integral stop valve prevents air flow through the pump during "OFF" periods. When the PCM provides a ground circuit for the relay, battery voltage is allowed to power up the AIR pump and integral stop valve. The AIR pump motor is protected by a 20 amp fuse and has its own remote ground.

Check valve
The check valve prevents back flow of exhaust gases into the pump in the event of an exhaust backfire.

Necessary plumbing
As shown in image.