Speed Sensor

[Kryptical]

I have a 99 mercury cougar v6 5 speed and the speedometer started acting up it workes fine then somedays it doesent work for like 5 or 10 minutes i thought it might be a speed sensor but my check engine light isnt on does a speed sensore always throw a code also what else could it be

[dalaster88]

When my Speed Sensor went out, it was going down the interstate and the Speedometer just flat lined... Then when i went to an exit and try to drive back on the interstate, it wouldnt go past 3rd gear. Mine is an automatic so i dont know if its the same for manuals. But maybe speed sensor or loose wiring on the speedometer.

[macnoon]

what else could cause this? I have the same problem but I changed my VSS. MY speedo was out completly before the change, but now it jumps around and messes up gearing and so on..

[tuka]

lol @ this post , anyone know the answer?
i was going 200 km/h , 120 MPH twice and my speedo started to move back and forth at that speed , i notice sometimes my speedo jumps around for no reason sometimes when i hit a bump in the road , it started to move around for no reason a long time ago =(

[macnoon]

yep yep..same thing :P anybody?

[skater]

If the speed sensor is okay and the car is otherwise running fine, I would start to suspect the cluster. Unfortunately the only way I know to test that would be to swap clusters with someone to see if the problem continues.

[brapple]

what do you mean it was acting up? was it jumpig around when you where stopped or at speed?

I had an issue with voltage because of a circuit breaker I was using and when the voltage got low the speedo needle would jump around on its own at idle .... I would check the charging system to make sure everything is good.