I have done thousands of autos, with many different helis in the past, that did not have a driven tail system. Most of these autos includes a 180 degree or 360 degree turn. The 180 degree auto was a maneuver required, at the end of class III AMA and FAI/F3C competition schedules, for many years, before any of our helis had driven tail systems. We even could complete 360 degree turning autos without a driven tail system. What a driven tail allowed us to do now, is backwards autos and to perform some 3D maneuvers, such as flips & pirouettes during the auto.

If yours turns 90 degrees from a hover auto, then I would suspect that one or both of the bearings that support the mainshaft are worn and/or your gyro/servo combination does not react fast enough to hold it as the tail rotor slows to a stop when the torque from the mainrotor disappears.

Of note, is that you can set any heli that does not have a driven tail system, to do simpler autos as if it does have one, by simply setting the throttle settings to a touch higher idle, so that the clutch engages just enough to turn the tail rotor slowly. This setting will be far lower then that which would engage the auto bearing that turns the main rotor. Consequently your main rotor would still be in the autorotative state, but your tail rotor would be now turning fast enough to provide basic t/r control.

This will not provide enough tail rotor to do 3D maneuvers or pirouettes while in the auto, but for standard autos, you will have more then enough t/r control to hold the heading you want into the wind.