Aircraft will not level out using autopilot

[Adam]

This problem has only just started, so I'm wondering if there is a setting I have inadvetently altered somewhere.
If I use autopilot on any of the FS 2004 jets to climb to a set altitude, the nose remains too high when it reaches altitude, the speed drops and eventually the plane stalls. At no time during the climb can I get the speed above 320.
I have reinstalled the simulator several times!

Any help would be appreciated.

[garymbuska]

Will they hold a low altitude say 5,000 feet and maintain it without stalling?
 Have you tried to delete your fs9cfg file if not removing and reinstalling fs will not do a thing for you. Just rename your orignal FS9 cfg file than crank up FS it will rebuild it and see what if any effect that has.