The problem of uncontrolled rotating is often caused through wrong physics parameter. Try to reduce the gravity value or mass of your wheels.

Edit: I tried a lot and the solution for this problem seems to be the physics frame rate. The variable "ph_fps_max_lock" is set on 70 on default that the gamestudio physics is able to run on old/slow computers as well. For a really smooth quite complex physics car set this value on 300 or higher (depends on your pc, more than 500 will slow down very much!). I put this value after ph_setgravity. The problem of uncotrolled movement disappeared, the stearing is quite smooth.