Transmission only shifts at high rpm's
I tried a search for this problem, and it seems to either the b2 piston, the vacuum modulator, or the bowden cable. My 1986 560 SEC sat for about two months without use until I replaced one of the fuel pumps. Now, for some reason, it won't shift into third below 2,200 RPM, or into 4th below 2,800 RPM. The fluid level is fine, and I plan to have the fluid and filter serviced. Has anyone had a similar problem? I tried changing the linkage throw to the bowden cable, but it had no effect. Any suggestions would be greatly appreciated.
1986 560SEC: 150,000 miles, runs great, but I've got to sell it (too many cars for one man)
1987 560SL: 122,000 miles, used to run poorly, now (thanks to forum), runs great!
1997 GMC Jimmy: Turned out to be a turkey.
1989 T-Bird Super Coupe: 150,000 miles, still runs great. Ford got it right.