I have a 1993 Mercury Sable, It run's great, I drive it all the time. But here is the problem, I have to shift it by hand. I have to pull it down to low and then shift up. When I stop at a stop sign, it will not shift back down. I end up taking off in high gear.Also the speedometer does not work. Other then that She's a great car, a station wagon. A 3.8 engine,auto,air,power every thing, sun roof. I have been told it's the speed sensor. I have been told it may have 4 to 6 speed sensor's. Which one? Where?...Need help! Thank's