When I parked my truck last night, I turned the key off but it all of a sudden went very loose. Now it will turn back and forth with no resistance. I can turn it all the way forward and it will still engage the starter and it will start and drive fine but I have to unplug the distributor to kill the motor as the key will not shut it off. Plus, I have to unhook the battery when it's not running as all the power stays on (fuel pump, radio, etc) even with the key completely removed. What broke?

 

Changed the Key Lock Cylinder and still have the same problem

 

You have a bad Ignition switch.
The key tumbler does not cause this as you have found out.

 

There's a cast aluminium piece between the lock cylinder and switch that breaks also. Could be that or the switch.

 

i say bad ignition actuator. 99% of the time it breaks in a no start situation, but i have had 5-6 that broke in a start but no shut off situation.

 

My brother works at ford, he told me to pull the column and he will take it to work and check it out

 

dang!! i just realized you have a newer truck. i never messed with one of those, all i did were the 91 and older trucks.

it must be nice having your own in house dealer mechanic!!!

 

TJC hit it, broken actuator.