My key will start the car but it wont turn the car off i have to unplulg the distributor to kill theh car. Also the ignition switch in the car rotates all the way around but it has always done that it just recently started not working to turn the car off.the key will turn but the car will still be on. what could be the problem i took it to a mechanic with a new ignition switch and he said that wasn't the problem

The ignition switch is an electrical part. The lock cylinder is whre the key goes and it activates the ignition switch. If you pulled the lock cylinder out, you could operate the car with a screwdriver.
Either you have damaged the ignition switch where the lock cylinder goes into it, or the lock cylinder is damaged where it fits into the ignition switch.

this is 96 taurus, don't have 92 sorry

Section 11-05: Steering Column Switches 1996 Taurus, Sable Workshop Manual
REMOVAL AND INSTALLATION Ignition Switch Removal

1. Disconnect battery ground cable (14301).
   

1. Remove lower instrument panel steering column cover (04459).
   

1. Rotate ignition switch lock cylinder (11582) to the RUN position.
   

1. Disconnect the ignition switch electrical connector.
   

1. Remove the two screws retaining ignition switch (11572).
   

1. Disengage the ignition switch from the actuator.
   

1. NOTE: A new replacement ignition switch assembly will be set in the RUN position as received.
   
   Adjust the ignition switch by sliding the carrier to the ignition switch RUN position.
   

1. Make sure that the ignition switch lock cylinder is in the RUN position. The RUN position is achieved by rotating the ignition switch lock cylinder approximately 90 degrees from the LOCK position.
   

1. Install the ignition switch pin into the actuator. It may be necessary to move the ignition switch slightly back and forth to align the ignition switch mounting holes with the lock cylinder housing threaded holes.
   

1. Install retaining screws. Tighten to 5.6-7.9 Nm (50-69 lb-in).
   

1. Connect electrical connector to ignition switch.
   

1. Connect battery ground cable. Check ignition switch for proper function, including START and ACC positions. Also, make certain that the column is in the LOCK position.
   

1. Install lower instrument panel steering column cover with screws.
   

• The ignition switch is cycled through rotation of the ignition switch lock cylinder (11582) through a pin which is part of the ignition switch.
• The ignition switch lock cylinder also controls the mechanism which provides a positive lock for the transaxle linkage and the steering system.
• The locking mechanism is located in the steering column housing.

• ACC
• LOCK
• OFF
• RUN
• START

• The ACC position operates while the steering and transaxle remain locked.
• The engine shuts off when the key is turned to the OFF position without locking the steering or transaxle.