Hey CONNIE ARNOLD POTTER,
I have attached the wiring diagram for the circuit you are having issues with.
The ignition barrel itself is not part of the key interlock. There is an ignition lock solenoid fitted behind the ignition switch.
I would advise the probable cause is the transmission range switch (PRNDL switch in the diagram)
If this switch is intermittently not contacting then shifting out of and back into park a few times will sometimes get it to sit in the right spot to make contact.
You could also have an issue with the bushing on the shift cable being worn and causing play in the actuation of the switch.
I have attached instructions on how to replace this switch.
When doing this I would check the bushing in the end of the shift cable and replace if worn.
To make sure it is the switch that is the issue you would have to test for voltage at the lock solenoid and the PRNDL switch when the fault is happening and see where the problem lies.
Hope that helps, let us know if you have any further questions.
Images (Click to enlarge)
Tuesday, March 26th, 2019 AT 9:37 AM