Stalling problems, to crank and wont start sometime

I was driving and my car would stall so my mechanic said it was the catalytic converter had that change, then it drove good one day next day it stall again, then it became ignition control modules, coils, tune-up, and I did oil change, change the air filter. after all that my service light stop coming on, yesterday it would start it crank but wont start. No one know what it could be because the machine is made for a 1996 and present cars.....plz and at my last with this car...b4 I junk it!