98 2.4 ltr charging problems

I have a 1998 Grand Am with a 2.4 ohc engine.I have been having problems with the battery light comming on and within a short time the car dies.I have had the altenator checked along with the battery,both checked out good.Struggled withthis problem for 5 days then one day it worked,and has worked for about 3 weeks.Today the problems started again.I have checked the wires from the battery to the starter and to the altenator and from what I could see,nothing "APPEARS" to be wrong.Please help with any information possible.
Thanks

My first guess would be a poor battery ground connection to the frame.

I assume your instrument panel has a volt meter gauge. When your car is RUNNING this gauge should be read between 13 and 15 volts and that is your alternator voltage.

What is this gauge reading when the battery light comes on?

If you want to read your battery voltage on this gauge the engine must be off and the key in the run position and the voltage between 12 and 13 volts.

Make sure your battery connections are clean and tight.

Your alternator may only be failing when under heavy load(lights, heater,radio,wipers)causing your Alt to overheat and fail.

more help>> http://www.aa1car.com/library/charging_checks.htm

no gauge, just the battery indicator light.Thanks for the link.I will double check eveything you mentioned, and what was on the link.

had batt charged and tested...good
had alternator tested......good
per the link that was given to me i performed the tests to find the problems, and it pretty much comes out that i might have to change the ecm.Takeing it to a dealer to verify this is the problem.