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Air Injection: Description and Operation

AIR System:




AIR Operation:





To reduce HC and CO emissions, this system injects air into the exhaust ports to accelerate oxidation. The air management valve (AMV) introduces air from the air pump to the check valve on the air manifold or diverts the air to the atmosphere. AMV mode is controlled by the electronic control module (ECM). The ECM calculates AMV mode using various inputs, including coolant temperature and throttle position. A hose supplies intake manifold vacuum to actuate the AMV.