Start car

Have it scanned for trouble codes. That's always a good place to start. Your computer has useful information stored in it that can be used to address the problem.

Thanks where do I get this done at auto zone.

Apparently they will do it for free (and probably other auto parts stores will too) if you just stop in and ask them too. At that point you may want to consult a mechanic before jumping in and buying all kinds of expensive parts, but at least that will give you some direction.

The problem on my 2003 Grand Prix GTP was the Camshaft Position Sensor. The engine was dying in stop and go traffic. It also died when I'd come up on a red light and take my foot off the gas. The CPS degrades over time from heat issues. It doesn't throw codes when the car dies. There is no test for it. The car runs after a restart but can die in traffic without warning. I had the CPS replaced at an independent shop because the dealership couldn't see it throwing codes, which it doesn't. I basically had to tell them I had already determined what the problem was and I just wanted them to replace the sensor for me. They did and it has run like it's brand new ever since. Best guess I ever made with a car. It was mentioned on another string on this site but I don't remember where I saw it. Good luck.