Coolant Temperature Sensor
The engine coolant temperature sensor detects the temperature of engine coolant and supplies the information to the electronic control assembly. Signal from the engine coolant temperature sensor affects, air/fuel ratio, engine idle speed, EGR flow, purge gas flow, fuel pressure, injector timing (turbocharged engine), boost pressure (turbocharged engine) and ignition timing (turbocharged engine). The engine coolant temperature sensor is threaded into the engine water passage near the thermostat housing.