Air Injection System - Vehicles Over 8500 GVW: Operation: Notes

Air pump(s) is mounted on front of engine and is belt driven. Intake air flows through an external air filter to air pump(s). Air flow from pump(s) passes through control valve(s) and air pipe(s).

Air flow passes through check valve(s) and enters exhaust manifold. Purpose of check valve(s) is to prevent a reverse flow of exhaust gasses from damaging air pump in event of a backfire or pump drive belt failure.