System Description
Effective control of exhaust emission is achieved by an oxygen "feedback system" to the ECM. This "feedback" is accomplished with the HO2 Sensors. Once the HO2 Sensor reaches operating temperature, the sensor generates a voltage signal to the ECM that is inversely proportional to the amount of oxygen in the exhaust. This voltage signal is used by the ECM to calculate the fuel injector pulse width to maintain the ideal 14.7 to 1 Air Fuel (A/F) ratio. This is the ideal mixture because at this ratio, the catalyst works best to remove hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxide (NOX) from the exhaust.