Mostuey

I am trying to help the lady down the street!:-/ She let her brother in-law drive the car and it hasn't been right since! He says he replaced the ignition switch and cylinder and completed the relearn procedure that the junk yard told him to do but its still not right! It will start but idles up and dies. If you turn the key on and wait, the theft light never goes off, also I noticed that you can pull the key out with it in the acc position. My concern is that the used part is damaged so the bcm is shutting the car down. Should I replace the switch and cylinder with a new one or is there something I can do to save this lady some cash?
Any advise would be greatly appreciated, Thanks