Fuel Temperature Sensor: Notes

The fuel-temperature sensor is installed in the fuel line just before the high-pressure pump, and employs a variable resistor (NTC= Negative Temperature Coefficient) to monitor fuel temperature.

The fuel temperature serves as a measured variable for the following functions:

• Engine overheating protection
• Fuel injection rate calculation
• Calculation of the requirement for the pre-supply pump
• Pressure wave correction:

In the case of a Common Rail System with more than one injection, each injection triggers a pressure wave in the line from the rail to the injector and in the high-pressure holes of the injector. This pressure wave influences the injection rate of the subsequent injections. In order to be able to use injections with variable gaps, this influence must be minimized depending on the gap between injections, the rail pressure and the fuel temperature.