I just purchased a 2000 Sunfire, and when in park, if i give it gas, then let off, it spudders, and when driving it, after a while, it with spudder, and act like it will die, the check engine light was on, but now it went off. Before all this started happening, the car ran like this, but when driving, after about 10 miles, it would just die without ANY warning what so ever. thanks any help is great!

Run the codes via your local parts store. That should be able to pin point ur problem. I'm thinking fuel pump possibly. If u have a way check ur fuel pressure.