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Bad324
10-26-2004, 01:04 PM
My car will not start. A couple weeks ago I drained my battery and then jumped it and it has been working fine since then. Today after the car had sat for two days without me running it, it will not start. When i turn the key the only thing that happens is the dash lights up and just nothing. there isnt enough juice for the horn to beep or the radio to turn on. I'm guessing since I havent run across anythin like this before either my starter is fubared or my alternator is dead. how can i tell which one it is?

sicc
10-26-2004, 01:07 PM
u need a new battery. alternator comes into play once the car is started.

Bad324
10-26-2004, 01:14 PM
damn this battery is only a year old. i just didnt think it was the battery because in the 2 cars I have had it has always at least made the clicking sound or would attempt to start, this time it doesnt do ****.

sicc
10-26-2004, 01:17 PM
damn this battery is only a year old. i just didnt think it was the battery because in the 2 cars I have had it has always at least made the clicking sound or would attempt to start, this time it doesnt do ****.

ive gone thru the same 4 times w/ my GA [ 2 batteries and 2 alternators]. i finally got an optima red top battery [and a higher outpur alternator, but u probably dont need that] and it is 1 of the best things ive gotten 4 my car. havent had a charging problem since [been a year now]

Mike Jung
10-26-2004, 05:41 PM
My car will not start. A couple weeks ago I drained my battery and then jumped it and it has been working fine since then. Today after the car had sat for two days without me running it, it will not start. When i turn the key the only thing that happens is the dash lights up and just nothing. there isnt enough juice for the horn to beep or the radio to turn on. I'm guessing since I havent run across anythin like this before either my starter is fubared or my alternator is dead. how can i tell which one it is?
First thing: When you drain a car battery, you need to re-charge the car battery with a battery charger.
Using the alternator is the not the right way of charging the car battery (when dead); plus you could end up killing the alternator.

Your battery could be toast (need a new one); if it is & you don't take care of it soon, you will kill the alternator soon.

Your alternator could be weak, but not dead yet; but still need replacing.

I would guess battery or alternator (it could be both).

abusedgt97
10-26-2004, 06:51 PM
I would just recharge the battery and go from there, you can have autozone test them and charge them for free. When you install a new battery you need to charge it first or else it makes the alternator work twice as hard (as someone else said).

Bad324
10-26-2004, 09:36 PM
alright how much are optima red tops? I was lookin at gettin one last year but I was tight on funds. also do they fit directly or is there some modding that needs to be done? I think when I was researching it then I found the stock tray had to be modded but I cant recall

abusedgt97
10-26-2004, 09:51 PM
I want to say red tops are around 120?

Mike Jung
10-26-2004, 10:10 PM
alright how much are optima red tops? I was lookin at gettin one last year but I was tight on funds. also do they fit directly or is there some modding that needs to be done? I think when I was researching it then I found the stock tray had to be modded but I cant recall
Optima Red Top 'starter' battery 75/35 (fits our stock 75 size).

Optima Red Top starter battery 34/78 - would need some battery tray modding, if I recall correctly.

I want to say red tops are around 120?
For the Optima Red Top 75/35 size battery:

I hope it is cheaper than that.

As I have seen it for as low as $126Cdn [$105US] @ Sam's Club here.
Price Club has them for about $160Cdn [$133US].

I have heard people have said they paid $99US for their's.


If I had to buy an Optima battery again; this time I would go for an Optima Yellow Top 34/78 size 'deep cycle' battery & trim the battery tray.

Bad324
10-26-2004, 11:09 PM
Well I am running subs and occasionally i run my neons on the weekend nights or when im in a cruising mode. I assume the red top would be fine for that then?

zeddsdead
10-27-2004, 06:36 PM
same thing happened to me WITH the red top optima. and get this...the guy at autozone told me to fully charge the battery it would require i leave it for 12 hours not the usual 1 hour for regular batteries. bastards.

Bad324
10-27-2004, 10:01 PM
is there any way to test the alternator to see if that is the problem?

Mike Jung
10-27-2004, 11:24 PM
Turn OFF everything in the car.
Hook the car battery up to an automatic car battery charger like at about 10amps/hour.
When it says it is fully charge at the charging rate of about 10amps/hour; trickle charge it at about 1-2amps/hour for like 2-hours or until the automatic battery charger says it is full.

Next morning:
Read car battery voltage with a digital multi-meter...should be in the 12.5-12.7 volts neighbourhood.
Get someone to crank & start your car; with you reading the car battery voltage.
If it drops below (I think) around 9.6volts while cranking the starter motor, the battery capacity is shot (battery is no good anymore).

After starting the car (if the battery reads ok, in open circuit & while starting your car):
Go for a drive (with everything OFF) until the engine is up to normal operating temp (15 minutes or more).
Take a voltage reading at idle & in PARK.
It should be about 14.0-14.5volts.
If it isn't; your alternator is under-charging(/not charging) the battery & the alternator could be faulty.


When I had my stock alternator go bad on me; I noticed my car had less power, lights started dimming, & my idle voltage was at like 12.5-13.0 volts after driving (the dealer [while under extended warrenty] tested the alternator to be producing 12.1volts at idle) under-charging my battery.

It was weird that I noticed it before my car's warning light for my electrical charging system (which never came on).
I would charge my Optima Red Top battery for like 30-45 minutes every night after driving to work & back for a week (before I had time off to go to my dealer).
Damn, my Red Top took a beating & still powered my car.

abusedgt97
10-28-2004, 06:45 PM
Mike, a fully charged battery is 12.6 volts, also just for some info on some of the newer cars (hondas) the voltage across the battery at idle is 12volts, the pcm toggles according to the driving condition to aid in the alternators life. Nice test you wrote though. =)

You should go to autozone and have them test it, their equipment should be able to test the battery on load, off load, the starting curcuit, and alternator diode ripple. We have a midtronics at school and it is the greatest, determines batterys condition, and has a wireless printer that prints results on a reciept sized paper.

2002AmSE
10-30-2004, 01:29 AM
Grand Am's use the full 14 volts as long as the rpm's are at a level to where the alternator is spinning fast enough to provide power(about 1200rpm under load or 600rpm with everything off at idle after its been running a bit and the battery is fully charged)

It is really quick and painless for the AutoZone/Checker Auto test, their equipment is a small handheld device that can load test the battery and also test the voltage the alternator is putting out, took less than a minute for the test of both my battery and alternator at Checker Auto, I went in because I thought my battery was about to go on me because it didnt start one morning, but i found out that my cell phone charger had a short that was lower than the fuse rating for the plug and it drained the battery that night. Everything was fine though.

About the voltage while starting, I've tested it and was still able to start the car with it at 7.2 volts on my volt meter under the load of the starter and it started up, it sounded like it started a tad weak but it was still able to and the battery lasted about a month past that point. I suppose the normal voltage for a new battery would definietly be above that without any problems, but your mileage may vary, especially with winter coming.

About the Optima Red top: The 12 hour charging thing seems bogus to me, it sure better not be pumping anything above a 2 amp trickel charge during that time or the person who told you wants you to cook the battery.

Automatic chargers, in my opinion, shouldn't charge at 10 amps and then say complete and then require you to turn it to 2 amps, that is what a manual charger is generally supposed to act like. My automatic charger charges at 10 amps and when it reaches the voltage it needs to be, it slowly tapers down until it hits the 2 amp trickle charge.

zeddsdead
10-30-2004, 03:31 PM
About the Optima Red top: The 12 hour charging thing seems bogus to me, it sure better not be pumping anything above a 2 amp trickel charge during that time or the person who told you wants you to cook the battery.



would you say the same goes for the yellow top...maybe he was thinking the red top was the "higher" grade battery of the two??