What causes a battery to die so quickly?
 

Yesterday I was comming home from a friends house (about a 2 hour drive), and my car ran perfectly, I did look at the voltmeter a couple times on the way home and it was running around 14 volts, maybe 14.5 ish, so i know my alt was working fine. I get home and let my car sit for about an hour, (i didn't leave anything on) and my battery is dead. Not enough juice to turn the starter over, barely engough to bring up the headlights, not enough to play the CD player.

What caused the battery to die like this. My dad told me that sometimes the lead plates inside a battery can warp and touch each other and cause it to die. Is this true.

I don't know how old the battery is, It was in the car when I bought it a year ago.

Take the battery to autozone or the like. They have FREE testing to see if the batery is bad or not.

Could it be that your battery terminals are rusted and not getting a good connection. Happened on a few of my friends cars.

I just jumped the FC and it started fine, but when ever i used something like the lights or brakes (anything electrical) the voltmeter would go nuts, way up and way down, i'm guessing this is caused by the shit battery but no clue why.
I drove the car around for about 10 min and then tried to start it again, nothing. But this time i parked it at the top of a hill so i can just roll start it next time.

I am guessing your alternator is foxored. Take it to an autoparts store and have it tested. If its bad its FD alt time. ;)

I took the battery too napa and it tested fine. Like 600 Cold cranking amps when it was rated for 500.
I don't see how the alt could be bad if it will hold 14-15 volts all day, but i guess its gotta be one of the 2.

Wouldn't the car die if the alt wasn't working? After i jumped it, it ran fine.

i heard that its the heat that gets to the battery, as you know the 7's engines run hot and heat drains the battery even faster..it may be different in your case but thats what i heard. one of my friends have put a heat sheild on it so it wont get as hot. just trying to help

If my alternator was broken, would the volt gauge show that i have 14-15 volts?

you might have a drain somewhere that's killing the battery when stopped too. If the alt. voltage is fine, then that is not the problem. Try cleaning the terminals really well and maybe even check belt tension.

its the shitty fc alternator. i have a brand new 80$ battery and the car wasnt started for a week (not my fault, about 2 hrs away from car:( )and the fucking thing is dead. so when i get some money scrounged up i am going to get the silverrotor fd alt kit.

its bad connections on the terminal, buy brand new terminals, and put em on, i almost gaurantee u thats what it is. cause my car was just doing that too, till i replaced them, wehn i would turn my lights on or anything it would die. so jus replace the terminals first, thats easy and cheap to do

brand new terminals.

Well I'm just a newb and a geezer at that but I'll stick my neck out on this one. Its happened to me a few times and every time the fix was good ol' H2O. First indication would be crackling in the stereo, then engine shuts down, and wouldn't take a jump. Popped the battery caps and checked the water level. Each time it was low I just added water(preferrably distilled) and it fired right up.

brand new battery.

No, you'd notice becuase your voltometer would only read 12V and then you'd die when the battery went dead.

OK guys, its deffinatly the battery.
I disconnected the terminals from the battery and ran some jumper cables to my dads car. The car started right up, tested the lines with my multimeter and got 14v. Then disconnected the battery all together from the car and it stayed running.
Also i cleaned the terminals with a wire brush, i know they are making a great connection.
I'll go get a new battery tomorrow.
What pisses me off though, the guy at NAPA that tested my battery today said it was fine, thats what really threw me off. Guess I'll boycott NAPA now.

Might as well go test the alternator at an Autozone... its free and takes only like 5 minutes to get off. It'll also save a lot of time if the problem persists.

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Wouldn't the car die if the alt wasn't working? After i jumped it, it ran fine. [/B][/QUOTE]

Actually I drove my rex about 100 miles when the alternator belt shredded apart. Never thought i would drive so... cautiously. Anyways, given that the battery was "dead" I see it intersting it doing that. I'd bet money on a corroded battery post.

Will make your battery not start your car even though the battery tests ok at napa (where they usually just hook up a wire directly to the top of the post and not around it. Also would explain why car runs fine once you get it started....

To test your alternator the ghetto way:
Start your car, jump it or whatever.
Disconnect battery.

If your car is still running, your alternator is working enough to power the ignition system, and the rest of your cars electronics. Mind you to turn off your stereo when you do this.


Anyways, I'd bet money on it being poor connections at the battery post.

Infact, buy a steel brush, and a package of new brass coated or stainless steel battery posts. It takes 5 minutes to install, and means you won't have the same problem for 2-3 years... infact id expect the battery to go out faster than some nice $5 battery posts get corroded. The really nice ones have some special electrode coating that resists corrosion.

MY terminals and posts aren't corroded at all , and i just took a wire brush to them today. I'm getting a really good connection.

Heres what i think: Person at NAPA was an incompetent fuck and I need a new battery.

Have you checked for a current draw on your car yet???

That should have been the first thing to check, if the voltmeter is reading fine.

If you have to ask how to do a current draw, please search, as it has been covered countless times.

I went and got a new battery tonight. Popped it in a it fired up very quick and turned over very fast. Problem solved.

BTW, I did check to see what kinda current draw i was getting when i was running the tests with my multimeter. It was like .08x amps or something really small. I'm guessing this is pretty normal because the ECU needs memory current and my stereo does as well.

That is a little high actually, and could draw your battery down in a week.

You want closer to .050 or .06... anything over .07 should be traced down.

I'll check it again tomorrow because i can't remember what number i got, just remember it being tiny, but if it makes that big of difference, i'm on it like stink on shit.