98 lumina problem

[hrslvr]

hello everyone, I hope someone out there has some advice for me. my lumina sat for 2 weeks, and when we went to start it, it wouldn't even click. so we jumped it, and replaced the battery. (it was older) it ran fine, for like a month and then it sat for a weekend, and wouldn't start again. we had left a cd player plugged into the cig. lighter, and thought that this was the problem. so we jumped it again, and it ran fine after that. we ran it everyday, for about a month. then i let it sit again for 3 days and it wouldn't start again. my concern is could this be the alternator going bad? if so, how hard would it be to replace it myself, (never done anything like this before). Or could this be another problem, like a bad ground or short. how can i tell if it is a short and not the alternator? If you have any ideas, or advice it would be greatly appreciated. thanks!!

[jeffcoslacker]

You need to take a look at it in the dark and see if there is a light staying on. Trunk and glovebox are common causes. Also the little map lights on the rear-view mirror. You can try pulling the fuse for the interior lights, and see if it runs down after sitting for a few days. Have seen alternators with damaged regulators draw power from the battery when the vehicle is sitting, but it's pretty rare. If it works fine while you are using the car, and only runs down when sitting, I think your alternator is charging properly. You seem to be dealing with some kind of parasitic load on the battery when the car is off. It used to be easy to find it with a test light, you could just test for power at the fuses when the car was shut down. Now, there is so many things that are supposed to draw current (ecm, clock, security, etc.) it's not as clear-cut. I have to say that over the whole time I worked in a shop, trunk lights were the biggest culprit.

[richtazz]

I agree with Jeff, either the trunk or underhood lights are the biggest problems, with the glovebox being third. IF it's not a bulb, then try unhooking the battery, let the car set, and if it starts, then you have a draw, which could be a bad rectifier in the alternator.

[hrslvr]

hey ya'll, thanks for your insight. I have checked the fuses, they areok and i know it's not the interior light or map lights, they have an auto off on them, but never thought to check the glove box, or trunk. will try that and see if those are the problems. At least I have an idea now of what to look for and go from there. Thank you so much!

[Kooterskkar]

OR your alternators goin bad and not charging correctly. Put a voltmeter on the battery when the car is running and make sure you're getting at least 13.5v.