Vehicle Speed Sensor
WARNING: This page is about a different car, the 2001 Mercury Villager. However, it is still accessible from the selected car via links, so may be relevant.
Vehicle Speed Sensor (VSS) is a magnetic pick-up that sends vehicle speed signal to TCM. Malfunction of sensor may cause harsh engagements of shifts. Lack of 4th gear, TCC lock-up, or engine braking in 2nd or 3rd gear may also be present.