The VSS or vehicle speed sensor is usually located next to the transmission on the underside of the vehicle. It will be a tube shaped piece with 2 wires coming out of it. It sends how fast you are traveling to the computer.
The speed sensor is a sensor that will show you how fast you are going. They are normally located near the wheels that has the power going to it and that is why when you are spinning the tires it shows you are going faster.
