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Air/Fuel Ratio Control System: Description

The Air/Fuel Ratio Control System controls the air and fuel mixture, which reduces fuel consumption and improves engine performance while reducing hydrocarbon (HC) and carbon monoxide (CO) emissions.

Control unit collects information from vacuum switch, engine speed (ignition coil or crank angle sensor), water temperature sensor, exhaust gas sensor, throttle valve switch, clutch and neutral switches (manual transmission), inhibitor switch and battery.

On Federal models, barometric pressure sensor, vehicle speed sensor, starter switch and air temperature sensor are also used. Control signals air/fuel ratio solenoid depending on signals received from sensors.

Fig 1: Typical Air/Fuel Control Solenoid Valve
G38059