To be certain, you should:
* Consult your owner's manual: This is the best resource for specific information about your vehicle. The manual should have a diagram showing the location of all sensors.
* Use a repair manual: A Haynes or Chilton repair manual for your vehicle will also provide detailed diagrams and instructions.
* Look online: Search for "2000 Lincoln LS 3.9L ECT sensor location" along with images. You may find pictures from other owners or mechanics that can help you pinpoint it.
Be aware that the sensor is usually a small, cylindrical part with a single wire connected to it. It's often near other components, so take your time to carefully identify it.