Computerized Engine Controls (Gasoline Engines): Notes

The computerized engine control system monitors and controls a variety of engine/vehicle functions. The computerized engine control system is primarily an emission control system designed to maintain a 14.7:1 air/fuel ratio under most operating conditions. When the ideal air/fuel ratio is maintained, the Three-Way Catalytic (TWC) converter can control oxides of nitrogen (NOx), hydrocarbon (HC) and carbon monoxide (CO) emissions.

The computerized engine control system consists of engine PCM/VCM, input devices (sensor and switch input signals) and output signals.