Location of Oxygen Sensor in B Series Truck 4WD L4-2606cc 26L (1992)
Oxygen Sensor Output Voltage vs. Air/Fuel Ratio
The difference in oxygen concentration in the narrow range of optimum air/fuel ratio causes a large voltage change that is easily measured by the ECU.
The oxygen sensor element only reacts efficiently with oxygen if the temperature of the element is around 300~C (575~F) or hotter. An electrical heating
element is incorporated into the oxygen sensor to help warm it up to operating temperature more quickly and maintain its temperature during times when
the sensor may cool off, such as prolonged idle or decelerating.
