Hello, I have a 1989 Porsche 928 S4.

It started out that the vehicle would not go out of second gear and would flare, but the reverse worked.

I drained the fluid, changed filter, cleaned the valve body out, installed shifter kit.

It sounded smoother but nothing changed.
Then I disconnected the bowden cable from the throttle house, it will stay in second and not flare, but reverse does not work, it will go forward in neutrel, and still stays in second. it seems liks 2nd, 2rd, and D selectors are all second gear.