For awhile my speedometer has been acting up. Before, it would read fine for a good amount of time and then jump around pretty close to my actual speed. Now, it works sometimes but usually just sits at zero. When it started a few months ago i took apart the gauge cluster and checked the wires and points on the cluster and it all checked out. My only guess would have to be the speed sensor on the tranny finally went bad. The car is a 90 300zx with 337,000 miles on it. Do you guys agree with the speed sensor or is it the speedometer after all. I checked on TT.net and the replies are pretty mixed up. Let me know what you guys the best place for a replacement part would be... thanks, JEFF