New to the site, and I need HELP, Electrical issue
 

My girlfriend's son has a 2001 Chevrolet Monte Carlo SS with 158,xxx miles on it.

A couple of weeks ago I replaced the upper and lower intake gaskets and things seemed to be great with the car. He drove it for a few days no problem and then the battery stopped charging. I took the alternator off and had it tested and it tested bad, so we replaced the alternator, everything worked great, so I thought. Well then I thought maybe it was the battery so now it has a brand new battery and alternator and the battery still drains.

So I don't really know what to do, I guess I maybe have a short in a wireharness? Does anyone have any idea what and where I should check?

Is there a sound system in the car, maybe it's draining the battery? Maybe a light is staying on?

I would start by making sure trunk,glovebox, and underhood light are turning off, also check voltage on the battery, their may be corrosion in the battery cables making it poorly transfer power. And of course , welcome to the site!

Thanks for the suggestions guys. No lights are staying on, and he does has an aftermarket cd-player that we installed about a year ago. The thing is there is so much draw that the battery charger can't charge the batter at 10amps. I'm thinking there has to be a really bad short somewhere if this is the case, I just don't really know where to check.

I'd start at the battery and work my way around the entire electrical system starting with the charging system. My wife's car was not starting without a jump and then would die out. It was the battery cable on the auxiliary post. It was cracked and not making good contact. Something like that could cause a draw.