TownleyBA

I've read the other threads, and found no real help. I checked my car for drains. I have less than 2 mili amp drain, even with the alarm running. The battery goes down every week or so if I don't drive it. It has a yellow top optima, this is my fourth optima. I have had the red and yellow. The only other problem I have noticed it when the car is idling the voltage gauge is like 8 or 10, once the rpms come up it puts the gauge at 14 or 15. That still doesn't explain the battery issue, because I can charge it completely and let it just sit and it will still drain. I have looked for a drain repeatedly but there is never anything higher than 2 mili. Any ideas? Thanks

NINÅ

<CENTER><B>
When you measure draw you had you hood up and
you disconnected your hood lamp to get an accurate reading.
Some hood lamp switches fail in a manner that they stay on
even when you close the hood.
In your dark garage look under the car to make
sure it is not staying on.</FONT>
</B><FONT COLOR=F3399><H5>
“If people drove any slower they’d be going backwards.”</FONT>
<FONT COLOR=FF66FF>NINÅ</H5></FONT>
<P>
<TABLE BORDER=9 CELLPADDING=8>
<TD BGCOLOR=black>
<B><H3><CENTER>REFUSE
TO
LOSE<p></TABLE></CENTER>

DENN_SHAH

iTrader: (1)

getting an 8~10 volt reading at the battery with a DVMM at idle means something is not right.
it sounds like your alt is dying.
that type of battery needs to be recharged at a very low current setting for at least 18 hours, 24~36 hours would be better.

TownleyBA

my Battery is in the rear well area. So my hood is shut when I am measuring no drain. Also if I trickle charge it, and then let the car sit for a week it will still be dead.

Dracul

i agree that 8-10 volts isn't normal.. i'd say drive over to adv auto and have them test the alternator and battery.. just make sure the battery is fully charged when you go over otherwise you won't get a accurate test.

even better if this is you have another vehicle to run, take both the alternator and battery out of the car, and take them to advance.. the machines inside are a lil better than just the portable tester.

TownleyBA

I have tested both and they came back no problems

lilmisshottang

Hello if you ever figure this out please tell me too my husband is haveing exact same issue and everything test out fine....He has a 1989 camaro w/ 305 FI GOOD LUCK.If you find the awnser e-mail us at Lilmisshottang27@aol.com

Jza

There's not much to a charging system, so you gotta start ruling things out.

If you say it dies just sitting for a while, there's either a drain, or the battery
is no good.

Since it's a yellow-top, there's no battery maintenance to think about. For that other poster: if you have a battery that requires maintenance, then check the electrolyte level. If it's low, the battery will act charged, but will rapidly drain with any use. Top it off.

Next, what are you testing the battery with that says you only have a 2mA draw? Try another meter.. If you get the same result, that would rule out faulty diagnostic equipment.

This suggests an intermittant parasitic draw. It's not there when you look for it, but will appear out of nowhere and kill the battery.

Next time you check the amperage, wiggle wires, connectors, rap on components and watch the reading. Do it at dusk or in low light so you can see sparks if there are any anywhere.

Low voltage at idle usually points to a bad alternator, but definitely check grounds. Scuff all the ground connections you can find. Make sure the block is grounded to the body, and the subframe.

Check the fuses and fusible links. A partially blown fuse or link (though unlikely can happen) could cause this. The brown wire to the alternator is connected to the FAN fuse.

Check the red wire going to the alternator (the thin one in the plug, not the big red one) has a fusible link.

That's all I can think of right at the moment. Let's hear back from ya'll so we can get it fixed.

Rebuildman

If you disconnect the battery and let it sit for a week will it start the car after you reconnect it? Yes? You have a drain on the battery. No? Bad battery.

Not charging at idle:
Have you changed the pulley diameter on the alternator or the the drive pulley? Size matters, in this case.

TownleyBA

I'm unable to do to much testing currently, however if I let the battery sit (disconnected) then reconnect it the car does start. This points to a drain, I'll have to try testing again, but I did test it with a couple different testers. As for the altenator, I did put on the pulley kit. However it did the same thing at idle with the factory pulleys. Since I haven't been able to work on the car it is just sitting. I did run the battery back to the rear, but all of these problems were there even before that, and I used wire that was plenty thick to make up for the distance, in other words I did it right. I had an 84 camaro that had a similar problem but it was the power door locks actually causing a drain. I might start pulling 1 fuse a week to see if that stops the drain, but since its intermittent who knows. thanks for all the ideas to everyone who replyed. I appreciate any further ideas and I will certainly let you know if I figure it out. Thanks - Brian

Rebuildman

As far as the alt. charging at idle, if you check any factory test procedures you will find that they call for above idle rpm's, like 1200 or so. I have the same problem with any older 10/12 si type alt., a smaller pulley on the alt. will spin it faster, or a larger drive pulley. You mentioned 8-10 volts at idle, this should be battery voltage, since the alt is not spinning fast enough at 800 or so rpm. So either the battery is at low voltage to start with or there is a huge draw from something.
Where are you taking the reading? At the battery or on the alt.? Should be the same at either place since the two are connected. Does the voltage go to 14.5 when you up the rpm's?

Rebuildman

Sorry, I re-read your post and answered a couple of my questions. I guess you are looking at the volt meter in the dash, try hooking up a external meter at the battery and see if it agrees with the one in the dash.
Again, with the car at idle the voltage is reading the battery voltage so 8-10 volts is a drained battery.

Grim'91Z

I'm having a similar problem. This morning I noticed it took a while longer to start, like it was struggling. So I drove to school, and as I was driving I noticed the volt meter drop to almost the red (below 8). So when I parked and turned off the car, I decided to try to start it. Nothing. Heard a click, accessories came on, but no spark or anything. Pop the hood and check the terminals, seem good (but the battery looks pretty old and shot). So I get in and try to start it again, nothing. So I forget about it (time for school to start) and come back 5 hours later. Try to start it again, hear a bunch of clicking, accessories don't come on this time, and nothing starts. I'm thinking it was something minor like a dead battery, but yesterday the battery was fine, so maybe the alt. is bad. Any idea as I am pretty inexperienced with this? Hope the descriptions help a bit. Thanks in advance.

Rebuildman

'The battery is fine' ? But it will not start? How did you determine the battery was fine? When everything is working correctly the alt. will put out around 13.5-14 volts at the battery, at around 1200 rpm and above.
You should be able to load the electrical system: headlights, blower motor, radiator fan, ect.. and still read over 12 volts at the battery. A seperate volt meter for testing is usually a good way to check output and also verify your in car volt meter is accurate.
If you are running the stock alt in your '91 I believe it is the 'CS' model and will have one large battery wire and another plug with four wires? Make sure they are connected. You can also try touching a screw driver to the bearing on the back of the alternator while it is running, should be magnetized, which checks the rotor for excitation.

Grim'91Z

I asked a bunch of guys on another forum, they all tell me it's the battery.

Blackhawk355

have you checked all your grounds, theres a small wire that grounds to the body from the battery and check the ground that goes from the engine to the firewall, if one of these are disconnected, it cause it to do this. if both are disconnected, the only time its going to charge is when you put your foot in it a little.

Rebuildman

You can have the battery tested for free at most auto parts stores but It needs to be charged up first.
Before you buy a new battery the charging system needs to be checked for proper operation. But if the wallet is fat, and time is critical, spend away.

NEEDAZ

That sounds like the alt. not the battery. But the battery could be bad now as well.

Grim'91Z

Replaced the alternator, all is fine. A new battery is probably due anyway, Interstate I hear is the way to go (or Optima if I feel like spending more).

Edit: No, the wallet is NOT fat, and time is of no issue to me.

juansupreme

hey,
I had an Alt that did not charge went to Autozone and swaped it for a new one, same problem. I was told that it might be the BATTERY CABLE (ha ha) everything checked out right........So it has been raining in NJ for 5 days now I can't work on my car cause I work on it outside, So I took my car to a Autoshop
and The reason that the new Alt was not charging was the The red wire that tells the Alt to charge was grounded to the HOT Exhaust manifold(melted on) I had all the simptoms of bad starter, bad Alt, bad battery cables Bad Bad Bad Charging system. and All it was , was a grounded positive cable comming from Alt and going to Starter

Grim'91Z

What the hell!?!

I know that wasn't my problem, but who the hell did that?

taonindo

to find a draw i disconnect the neg. side of the battery and hook a test light between the battery post (negative) and the cable if it lights there is a draw...start pulling fuses untill it goes out .... good luck......tao

FireBirdKnight

if u have a stereo system with a amp... after ur car is turned off check if the amp is still recieving current that will cause a heavy drain over time

crisroc

what happens if you do this but the light still dosent go out?

what does that mean?

88blkbird

If your vehicle has a computer there will always be a small , very small, drain and the light will NOT go out but it should be dim.. if it is bright you have a draw, just make sure no doors are open or hatch lights on or even the light inside the console to illuminate the console well.. that light will draw the battery down.. and you can't see it on unless you are looking for the problem

taonindo

sorry i never thought about the computer system might draw...my knowlage of cc system is nada...probably why i got rid of mine...maybe someone else can tell us if they can be disconnected safely for testing ??? tao

NEEDAZ

A computer, or a radio, or an alarm, ...
Forget the test light, get an amp meter in there. Get a number that means something. This "How bright should the light be?" is going to wast a lot of your time.

88blkbird

If its a waste of time for him you might want
----------
If its a waste of time for him you might want to explain miliamps to him before sending him to an Ohmmeter/voltmeter to do the testing. Yes that is the proper test to perform.. it might be best if someone more familiar with these systems helps him so he knows for the next time ..

NEEDAZ

Hope you don't think I was stepping on your toes. I could just see the thread going in that direction. Thought we could cut it off. If he needs some help with using the meter, there's not time like the present to learn, we'll help. And learning now could save him time down the road with the next problem.

88blkbird

No crushed toes here, just trying to help a fellow driver without throwing him to the fire, electric concepts can be difficult to grasp.