Oil Temperature Sensor For ECM: Description and Operation

Engine Oil Temperature Sensor

Engine Oil Temperature (EOT) Sensor:

The Engine Oil Temperature (EOT) sensor is a thermistor whose resistance decreases as engine oil temperature increases. The Engine Oil Temperature signal is used by the PCM to calculate fuel quantity, injection timing and glow plug operation.

At low ambient air temperatures, and oil temperature below 70°C (158°F), low idle is increased to a maximum of 1300 rpm to increase engine warm-up. Fuel quantity and timing is controlled throughout the total operating range to provide adequate torque and power.

An Engine Oil Temperature signal detected out of range, high or low, by the PCM will cause the PCM to substitute a temperature based on ECT to be used for operating purposes.