I have a strange problem with the car. The battery never has enough juice to start it, but when I jump it and drive it around everything works fine. The battery WAS charging before the problem got worse, but was slowly draining - first it died after a few days, now it's over night.

My headlights are bright enough, but when they are on, my signal lights blink REALLY slowly and the headlights dim everytime they come on.

Since the problem started I've noticed a slight squeeking sound from the engine bay as well. Is it perhaps a bad pully on the alternator that isn't charging the battery or just a coincidental noisy belt? Is a bad ground somewhere draining my battery?

The battery is almost brand new, only 2 months old now. The problem started 5 days ago. Does anyone have any suggestions for something to look for?

Well there are a couple ways to go about this.  There is the complex way with a volt meter and resistance checks and such.

But the simple way is, get your car fired up and check the voltage on the dash Is it Charging, if it is, move on to step 2.

Start pulling bulbs, the front and rear trunk are the 2 most important.  If your car does not have a front trunk courtesy light, thats OK, just remove the rear one.

Wait 24hrs, is the problem solved?   

Ok next up, get your owners manual or Hains out and look over the fuse block section.  Pull any fuses that are not needed for the engine.

Does it fix the problem?

Now I am sure the good Dr, or several other mechanics will come in here and explain the current draw method.  Which I can do, but not nearly as well explained as they can. 

Other things that can cause an issue is how your stereo is wired.  If they hard wired the amp and stereo into the 12line its possible an amp and stereo can kill a battery even if it looks like it is off. 

As for the other issues, a belt squeal is a sign the alternator is not charging correctly.

Always check all the grounds.  Make sure the braided cable is in good shape, its near the passenger side engine to battery area.  If you can't find it.  Add a new one.  You need to have a minimum of 3 ground points.  Engine to Battery, Engine to Chassis, and I add battery to to chassis as well.   Also make sure the ECM harness ground is good, its under the center console near the ECM bolted to the tunnel, (you'll have to remove the glove box)

           Not part of your issue but make sure the 2 grounds on the drivers side, firewall head are there and in tact.  There should be IIRC 4 wires in 2 eyelet connectors with rather large bolts holding them to the engine head.

 I'll leave the rest of the info to the more electrical experienced people.

The squeeking came back and the culprit was a loose belt. I went and loosened the bolt to adjust the tension and the darn thing snapped off and the stud is stuck in the alternator; totally rusted all to hell. Now I can't get it out since all my tools were stolen, can't get the belt back on and can't drive my car! ARGH!

Now I'm going to have to get it towed to a shop and get them to get the damn stud out. All this over something that was gonna take me a few minutes.

Bobz0r wrote: The squeeking came back and the culprit was a loose belt.

One of the first things I did when I bought my GT last year was to install the following...

Install it. Forget it. I love it.

Belt never squeals (no matter how hard it's raining). Belt never needs adjustment.

Read some info about it http://www.fiero.nl/forum/Forum4/HTML/039384.html - Here .