I have a 98 Taurus station wagon that is getting the code P0500 from the check engine light. That code calls for replacing the vehicle speed sensor. I first bought one from the parts store, installed it and the erratic shifting continued.

We pulled out the new sensor and put the old one back in and the car drove great for about 4 days until the check engine light came on again with the same P0500 code.This time I replaced the old one with a dealer bought sensor, still no luck.

Someone suggested that the problem might be the pcm or turbine speed sensor, so I replaced the tss with a new one and picked up a pcm from the junk yard and tried to install that. The new pcm gave us more errors because it wasn't the same as the original pcm.

Replaced the old pcm and now I am back to the original P0500 code, but after replacing the speedwith 3 new sensors I'm pretty sure that the problem is not the speed sensor.

Any suggestions would be greatly appreciated.

 

Have you checked the wiring tii see if it is chafed, rubbed, or shorted anywhere? Also look at connectors for corrosion. All a code does is gives you a circuit to start the diagnosis in. Lots of times the componet is at fault, but sometimes it is a wiring problem and there are no shortcuts there. Just look over every inch of it. If it is OK, then look to the PCM. Also if PCM is replaced it will need reprogrammed. Especially if you have a used one.