the car has always had an key problem but i just had work done replacing the rack n pinion.. drove the car home fine drove next day fine. then the car lock the key tumbler will not turn. the security light on the radio flashes. I bought a used ignition switch and tumbler. I thought fix great. waited the 10 min with key on great.. went out to get more keys drove to two stops and BANG.. key will not turn.. has to be some security thing.. how do unlock the key to turn and how to bypass this pos.