1. Open the hood of your 2008 Buick Lucerne.
2. Locate the coolant reservoir. It is a translucent plastic tank located on the passenger side of the engine bay.
3. Follow the coolant hose that leads from the bottom of the coolant reservoir to the engine.
4. The engine coolant temperature sensor is located on the engine block, just below the thermostat housing. It is a small, cylindrical sensor with a single electrical connector.
5. To remove the engine coolant temperature sensor, simply unplug the electrical connector and unscrew the sensor from the engine block.
6. Be careful not to drop the sensor into the engine bay.
7. Install the new engine coolant temperature sensor in the reverse order of removal.
