battery or alternator issue
 

I left the car sitting for some time. I started using it again and before you know it, the car starts to steadily slow down and turn off as I'm driving. My battery reading is at 10 and decreasing. I get it home and I figured that having the car sit too long and letting the battery drain out too many times might have ruined the battery. So i buy a new battery. Problem still exists and I think the alternator is going bad. A new alternator is very expensive and getting it rebuilt isnt too cheap either. Can the problem be anything else besides the alternator? Also, the car runs fine after I charge the battery, but the battery slowly loses charge over time.

take it to checker/autozone/napa, can test the whole system while the car's running.

I'm putting my money on the alt being bad. The battery is suppling all the electric for the car and will go dead as you drive it. I was a poor kid once, I know about these things. :) It is possible that you have some bad wires coming from the alt. There's a recent post on here about it. He had a bad wire at the starter I think. Check the grounds to make sure they are clean too. You are not getting power from the alt. Either the alt is bad or there is a wiring problem somewhere right after the alt.

If you do need a new alt, look for one on here for a used if cost is a big issue. I have seen them and I want to say it was around $400+ for an alt. for my 87 n/a. That's CRAZY!