battery keeps dying

[laprodigy001]

1998 gmc slt yukon 4x4 5.7l

problem started a few weeks ago.i was going to walmart and i noticed the truck a tiny bit sluggish.i put on the AC and it was not really cold and lacking a lot.so i stopped to shop with wife and came out after being in there a few hours and my truck was dead.it turned over a half turn each time i tried and then nothing.if i turned my truck in the on position the gauges would go crazy.but barley any volts. and when i looked under hood seeing if there was a loose connection i noticed my neg battery cable was really hot and had a slight smell of sulfur from it.so i tried to jump it for a while and it seemed like it wanted to go but every time i turned the key everything would die out.so i tested battery and they said it had a dead cell and only showing 9volts.so i purchased a used one from a junk yard and it started right away.showing 14 volts on the gauge.i only used it 2 times in the past week.and yesterday when i would drive the volts would drop from 14 to one line under.when i was at idle it would go back to 14V.i had nothing on,not the radio,ac, or anything.so i parked car at my and went to start it the next day and nothing.the under hood light is so dim its barley noticeable.everything drained again.the first 2 times i started it it started but seemed like a weak start.but once it was on it seemed fine.
does anyone have any ideas.is there a way autozone/advance could check my alternator if i brought it in.and how accurate would that be.thanks

 

[retorq]

That is a good start, I would replace that battery and the cables no matter what though ...

 

[moviewithnotitle]

I had a drain issue a long time back. Total mystery that had me baffled for nearly a year. If I left the truck from more than 3 days, it would barely start. Eventually found that the vanity light in the visor was one all the time. I wrapped it with a thick rubberband and since then no issues with draining.

I would do as Retorq said, then start looking for anything that could be on. At night you can easily find lights on that should not be. Then start pulling fuses till one sparks. eventually you will find it, given enough time of course!

good luck

 

[laprodigy001]

That is a good start, I would replace that battery and the cables no matter what though ...

I replaced with a used junk yard battery.should I just buy a new one. And go from there....if I get this battery tested and it says the same as last time.could something be killing like alt. And do you know how reliable the advance auto alt test are because I am going to bring it there monday.

 

[Dowsewashere]

My obs had the drives side vanity too. The just unwire it because the light would drain the battery. The PO spent month trying to figure it out.

 

[laprodigy001]

I will get the battery and alternator tested at autozone tomorrow and then see if I can get it started and see if its draining somewhere

 

[Donnie Yukonie]

Moved to the correct section , maybe I missed this somewhere but what battery are you using

 

[laprodigy001]

---------- Post added at 11:15 PM ---------- Previous post was at 11:13 PM ----------

this is the one i purchased and when i installed it.the truck started right up.had it a few weeks but only started it a few times.then one day went to start and nothing.

 

[laprodigy001]

Purchased a volt meter at Wal-Mart. And the truck jump started right away.I put ac, radio, rear defrost, wipers, light on and at the battery with meter it was reading over 13 volts with the load.and was reading like 13.8 with everything off.I thought with out load its supposed to be over 14v.

 

[Gzes]

My dads truck was not charging. Pulled alternator had it ***** it was good, had new battery tested it was good, took the alternator back out since I thought it was the voltage regulator and boom it was that. If your alternator has a voltage regulator it might be bad. Autozone can test the regulator aswell as the alternator