i have a 91 mustang gt with an aod trans. The trans has a problem. It doesnt want to shift on its own but if you put it in first and accelerate moderately then go to drive and back to first it shifts to second gear. It will not shift into any other gears. If you smell the fluid it smells new and it is clean and not burnt. It will not shift itself if you leave it in o/d or d it will stay in 1st unless you go to d back to first. i checked the tv cable when i bought the car because it had this problem whem i bought it. I put it away for the winter and now im wanting to diagnose the problem and fix it myself so i dont have to waste money on someone elses labor cost. I just went out and checked the tv cable again about a half hour ago and its still in adjusted correctly. The trans will down shift itself back to 1st when driving if i slow down to much and am not on the gas but it still shouldnt have done this because im still going about 25mph. If you put it in od or d it will stay in first and not shift out but if you give it about half shrottle and go 1st, drive, 1st in will shift to second, If you are in second and go to shift back into drive it acts like its in neutral or like theres no gear there. This is really frustrating me so im looking for any advice on how to get it going and not waste any money and find the problem before i pull it. Ive been told it might be the valve body.