Dual Air Pumps

Air Injection System:

SYSTEM OPERATION

The air injection system is composed of two belt-driven air pumps, two relief valves, rubber hoses, coolant temperature sensor, check valves to protect the hoses, and injection tubes. This system adds a controlled amount of air to the exhaust gases aiding the reduction of hydrocarbons and carbon monoxide in the exhaust stream.

Air passes through the plastic centrifugal filter fans at the front of the air pumps, and foreign materials are filtered out of the air by centrifugal force. Air is only injected to a point downstream where it will assist the oxidation process in the catalyst but not interfere with exhaust gas recirculation. There is no air switching valve, diverter valve, or air switching valve solenoid in this system.


CHECK VALVE

The check valves are located in the injection tube assembly downstream to the catalyst injection point.

The purpose of the check valve is to protect the air injection system in the event that the air pump belt fails, exhaust system pressure raises to an abnormally high level, or an air hose ruptures. This valve has a one way diaphragm which prevents hot exhaust gases from getting to the rubber hoses or the air pump.