2000 Pontiac Grand Am

Engine Cooling problem
2000 Pontiac Grand Am 6 cyl Front Wheel Drive Automatic 160000 miles

my car runs fine apart from it heats up after a short period of time which inturn makes the car jerk and acceleration is very hard, once I stop the car and check to see if it has enough coolant I notice that the surge tank has a tube that I guess lets out over flow but what concerned me the most was it was pouring out of that tube, would like to get a clue to what is going on so that I can try to fix it, could you help?
August 13, 2010.

It is coming out of the overflow line because of overheating, that is not the main issue. For overheating, check to make sure the radiator fan(s) are coming on. If so then remove and test the thermostat to ensure it is opening to let coolant flow through properly.

Aug 13, 2010.