speedometer wierd?

[Rjs4490]

99 gsr swap...ls tranny....my speedometer stays at zero but sometimes spurts up to the correct speed real fast then goes back to zero??...what could be the problem?

 

[Briansol]

check the VSS (vehcile speed sensor). it might not be seated properly inside the tranny.

 

[Matts96HB]

What B said. Either that, or the VSS is on it's way out. My sisters 97 Civic EX had this same problem, we later figured out that it was the VSS.

BTW, the VSS is located on the back of the transmission. It faces upwards. It is right along the edge where the bell housing and the engine block meet.