2000 Pontiac Grand Am Won't start, starts, won't start, star

I have a 2000 Grand Am, the car has a problem of occasionally not starting. I can start the car drive for days then it won, t start. Let it sit for a couple of hours and it starts with no hesitation. The engine turns over fine and acts like it wants to start but won't, let it sit and it starts and runs for days or weeks then it happpens again This has been going on for over a year. No codes on the computer to check for problem.