1998 Sunfire 2.2L, charging system problems

Hey Peeps, i am hoping one of you can help me answer this problem i have. 6 months ago i got my babygirl, (I LUV HER), but she is makin my life miserable and my dad and stepmom are about to kill me because i need to borrow money from them to bail my azz out because of my charging system problem. When i got her 6 months ago, i put an aftermarket stereo along wit subs in my babygirl, she has had no problems up until recently when i lost all power in my car and my battery was no good . I have since replaced my battery , starter and alternator and i still have a charging system issue .I took it into a garage they said the brand new battery was no good and replaced it . They did a diagnostic on it said it was charging fine, after i picked it up from the garage in less than 10 minutes of driving my battery light came on once again and eventually the ABS as well came on, my engine was reving higher and when i turned it off my battery was dead again. Can someone help me with what my problem might be , my dad looks at me funny while he's holding a knife in his hand??PLEASE HELP!!!!!!!!

Recharge the battery and install a capacitor on the power cable to the subs. You are taking more power from the system than the battery and alternator can supply and thus you are draining the battery. You can find them on E-bay for a reasonable cost.

We do not believe it was the stereo, considering when I picked it up from the garage my system was completely unhooked, and no power was going to my stereo, thats why the garage doesnt believe that may be the problem

If you are sure it's not the amp drawing too much power, then check your ground line on your battery. Make sure it is properly connected. Also, if you have charging problems, think about getting a gell cell battery. red, yellow and blue top batteries provide more current in cars with systems. Also, add another 4 gauge ground to your battery, as that will help with current flow.

If you have a system, I would do what GTP said and get a cap. It will help protect your battery from spikes. Especially when your sitting at a stop light, in the middle of January blasting your heat, your stero and have your defroster.

Hmmm... Because I am so suspicious of car repair dudes, I would make sure they put in a new battery. Watch them take it out of a box or whatever it came in. Also, before you roll out of the shop, take a voltmeter to the terminals and make sure you have 12 volts +/- 1 volt. Anything less can cause problems.

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You said your stereo was completely unhooked? What about the amp? Charge your battery up and remove power from your amp to see how long it lasts then. If you have a control line that goes from your stereo to your amp to turn it on, make sure it is not hardwired to the power input to your stereo. I have seen that happen before too. Also... think about these questions:

1. When you bought it, did you have the battery light on?
2. Did it ever come on before you put your system in?
3. If it didn't, how long after having your system in did it take for it to come on?
4. If it did, you obviously you don't have a stereo issue.
4. Who checked your charging system? Go to auto zone and they wil check it for free, they have nothing to gain really because they don't dignose what's wrong with it, they will just tell you wether or not the right amount of amps are coming from the alternator to your battery.

1st things 1st these little cars where not manufacturer for big stereo's. Look at getting a larger alternator.

Make sure you have fuse on amp line, and verify wiring of stereo ( HOT, IGNITION ).

A good test is take a voltmeter to battery read, start car with stereo off and read, turn on stereo and read then crank stereo and read. If no big jumps would rule out stereo, but since killing battery quickly woudl consider looking for shorts, did you bypass fuses by anychance as they may want to kick in if short detected.

Also easy test, is unplug stereo fuse and amplifier fuse and drive car and see if drains battery quickly. If so look for light left on somewhere in car.

Check any and all lights that are designed to come on automatically under certain circustances i.e. overhead lights, trunk lights.... that sort of thing. If they stay on when they are not suposed to, then check the switches that cause these things to happen. This is just a little amplification of the post above.

I a had a charging/voltage problem with my 95, it was fine at idle but when you put it in gear the voltage would drop to just over 9 volts while driving down the road.
It turned out to be the ground wires.
There is several hooked to the side of the frame under the battery.
The one that was the biggest problem was there was no ground from the engine to the chassis (do to corrosion in the wires). The battery ground is connected to the engine mount bolt at the trans housing.
There should be a ground wire to the chassis from the engine and the ground connection at the battery may or may not have one to the chassis.
I ran a new ground from the engine to the chassis and the problems went away.
This only showed up when the car was out of park, the ground point on the engine is also used by the transmission and it was back feeding into the trans or ecm looking for a ground.

IF you check the threads you will find these are known for ground wire problems under the hood.
Are your head lights dim? kind of yellow?
check it out let us know