New battery yesterday died today = bad alternator or ? possible use one from 92 325?

[voxleo]

Boo's 98 328 went kaput today while coming home from work after buying a brand new battery yesterday. Says that it started but while driving the lights dimmed, then radio quit, then ac died down, then eventually engine cut out too. Also says the battery light stayed on. even after the replacement...

He assumes its the alternator, but having dealt with various assumpitions previously, I figured it can't hurt to ask around where I found the unlikely solution to the LAST battery issue (a short in the trunk wiring!) That was his previous 92 325 - currently that carcass is the back yard, slowly being scavenged for useful bits. And since its there and has an alternator, maybe that one can be used in the 98 328 if that actually is the problem?

Currently its sitting in the Dominos lot a few blocks from here, and we're hoping to be able to get it home with something from the other cars carcass if at all possible since we have not a dime to spare until the job he's doing is done. Any help would be greatly appreciated. Is there any other weird thing it might be besides the alternator?

[voxleo]

EDIT>> a few bits of intel have been unearthed on the way to get the battery from the car and put in on the charger which make me suspect it might actually be another weird wiring/ground problem rather than the alternator:

1-while raining out - had been driving for about 10 minutes and started to turn right onto freeway when everything went dead for a second and then came right back online as he was turning.

2- recently saw a puff of white smoke from vent while driving (had been in the car for about 15 mins already

3- battery light stays on while car is running

4- gauges have "tweaked out" on occassion



Any ideas?

[brettski]

I'd start by seeing what current is being drawn with the car shutdown. Charge up the battery and see what load is showing on a multimeter.
Start the car and see if the Alternator is actually putting anything back to the battery or if the battery is being drained slowly.