Speedometer/vehicle speed sensor

ADOLELIZON

MEMBER
1998 FORD EXPEDITION
5.4L
V8
RWD
AUTOMATIC
208,000 MILES

I am having a problem where when I come to a complete stop and take off my speedometer does not move and transmission will not shift, but once I hit twenty to twenty five mph the speedometer kicks in and transmission shifts fine after that point and speedometer keeps up and is correct on speed until I stop again. So what could be my problem? It has never done this before.

1 Reply

HARRY P

MECHANIC
2,293 POSTS

You probably just need a vehicle speed sensor. This truck uses the signal from it to help judge when to shift gears. If the check engine light or ABS lights are on, get the vehicle scanned. The check engine light can be scanned by your local auto parts shop, and the ABS light can be scanned at some mechanic's shops or at the dealership.

The sensor is located on the tail shaft of the transmission of two wheel drive models and on the transfer case of four wheel drive models. If you can get a look at it, check to make sure that it is tightly secured and the the connector is tight. Also, check the wiring and follow it as far as you can see it, looking for bare spots and other apparent issues.

If you have a code for a bad speed sensor (and no apparent wiring issues) then replace your sensor. If you have apparent wiring issues, fix them and see how it does. If there are no codes and you do not see any issues, go ahead and try replacing that sensor. Let us know.