antitheft module

Hi agian,94olds regency98,Well it died on me agian yesterday. MY mechanic says it was not the crank shaft position sensor.When it does this the engine light flikers. it tryed to do it the day before ,i turned the key off and tryed starting it agian and the car ran great the rest of the day.The next morning started right up no problem,Then while driving it just died would not start and is now in the shop every time my mechanic has my car he has it for a week or so and never resolves the problem,Every time he says it is something diffrent.How do i know if im getting ripped off or not ,sure seems like a lot of money for nothing.IT really sucks''... to have a car but cant go no where .Thanks So Much you guys have been great taking the time to answer me.Anymore suggestions :banghead: Angie .