I have a 1986 Mercury Cougar LS with about 76,000 miles on it and a C5 transmission. I started having issues a few weeks ago with it not shifting from first to second and not going into third gear. I replaced the vacuum modulator, cleaned the throttle valve inside where the modulator valve goes and changed the fluid and filter. This did not work. When in drive, it still won't shift first to second and slips going into third and won't always go all the way into third. When you floor it in drive it will kick down to second and then shift back into 3rd/drive when you ease out like it is supposed to. I can't figure out if it is a sticking valve in the valve body, a governor problem, or if my TV linkage is messed up. So, if anyone has any experience or advice in this, I would appreciate it very much. Also, if anyone knows how much it costs to have a shop rebuild a C5, it would be good to know that as well in case I need to do so. I do most of my own work but I don't have the resources to rebuild a tranny. Thanks!