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Exhaust Emissions System - Air Injection System: Description

NOTE: For 1974-78 models, see AIR INJECTION SYSTEMS article in this section.

The air injection system reduces exhaust emissions by injecting fresh air into the exhaust gas stream as it leaves the combustion chambers. The oxygen in the fresh air, plus the heat of the exhaust gases, causes further oxidation (burning) of the exhaust gases, thereby reducing exhaust emissions. The system consists of a belt-driven air pump, a pressure relief valve, a check valve, a gulp valve (if equipped), air injection manifold, and various connecting hoses and pipes.