Fuel Temperature Sensor: Description and Operation

Engine fuel temperature sensor (EFT Sensor)






This is another resistive sensor. Located on the fuel rail it measures temperature of the rail rather than the fuel. The resistance varies with changes in temperature. The signal is used to increase the injection pulse time when undergoing hot restarts. When the fuel is hot, vapourisation occurs in the rail and bubbles can occur in the injectors. Increasing the pulse time flushes the bubbles away, and cools the fuel rail with fuel from the tank. The fault may not be evident to the driver, there may be a hot restart problem. The fault is indicated by illumination of the malfunction indicator light (MIL) on North American specification vehicles.