Steering Column Repair: Key dose not work in run position, ballast resistor, mustang gt

Question
I have a 1989 mustang gt it is a efi. I am haven trouble with the ignition the car will start an run when the key is held in the start position but will not stay running when the key is returned to the run position. I have changed the ignition switch already. I am wondering if it could be the key drive gear is missing. Would that cause it to have this kind of symptom?

Answer
Hello DJ:

You take me back 20 years...
I believe there is a component called the ballast resistor that supplies power to the coil after you release the starter.  If that part has failed, it will cause those symptoms.
It is a simple repair and should be available at a local parts store.

Good luck
Doug