I would also take a look at the TPS( Throttle position sensor) because I know for me, this little sensor is causeing me a world of hurt. As 1TuffSupra said make sure the car has had a tune-up. Check the plugs, and plug wires, and dont forget the intake. Does it stall when you give it gas or does it just run really rough? If it stalls when you give it gas check that the AFM(Air flow meter) is properly connected. All in all, just go through all the basic things.
-Joe