This has been happening over the past week now it seems. If it is really hot out and if the car temp gets close to 200 from stop and go traffic or just at idle the volt meter starts to drop down to about 11 or 12 volts. It will do this with no AC or fans going, no power to the audio stuff and no other things on(lights, etc..).
There is no light dimming so I don't think its the alternator. Does the battery need a recharge? It'* only 2 yrs old. Or is this a sign that I can go get my Optima battery.
I'll get a voltmeter on it tommorow and see what the volts say at the teminals(they are clean by the way). I thought I'd get some early opinions. Thanks, Seth.

I had my alternator go out twice in the last two weeks so I put a SSE 140 amp alternator on instead of the stock 105 amp. I was seeing 13.8 with the 105'* when they were good, and with the 140 amp I am seeing 14.0-14.2v with no load and with the ac, headlights on and stereo blasting I am in the 13.4v range.
I am thinking about replacing a few of the battery cables because there is a bare spot on the negative just under the ignition module, and because they've got 191,xxx miles on them and are probably needing replacement.
Which brings me to ask if Will or anyone else has the part # for any of the battery cables?
Stylez

Thanks for the tips Jr. Have to wait and get the verdict from the voltmeter.
I just understand why it suddenly decided to take a dip like that, used to always sit just under 14 with AC on and tunes going. Oh well, another quirky thing cars do.

Fogot to say I use a lighted digital voltage readout that plugs into the cigarette lighter. Small, and very usefull, just like dynomite.

The voltage will be the same at the battery terminals. The only way it can be different is if the voltmeter draws a lot of current, which it does not.

Does the voltage go back up to 13.5 or so if you rev the engine a bit, like to 1500 ?? If so, take a good look at the belt.

Otherwise, looks like your alternator is crapping out. Change it before you get stuck, and also you will damage the battery if you let it go way down.

Autozone has a lifetime alternator that they will keep replacing if it dies. Good insurance.

If you change the battery you may well be treating the symptoms instead of the disease. Get an alternator output test done to see if yours is on the way out. You can get yours out in 10 minutes and have it bench-tested for free at places like Auto Zone.

(Besides, if your battery does need a recharge, it'* only because your alternator is no longer doing its job.)

Sure sounds like your alternator is failing to me.
My Jeep was doing the same thing last summer. I changed the alternator and it'* been great ever since.

Left my magic book at home. If someone doesn't pop in here before I get home, I'll get you the numbers. How much do Optima'* run, anyway?

PM me your year and model, and I'll get the numbers for you.

Well the voltmeter test was reading about 13.3 volts, no problems there. I'll pull the alternator off as soon as I can, not possible in the next couple of days. Thankfully that'* covered under my extended warranty.

Optima'* are $$$, about 200 I think? Shop in town sells them for that, but I hate that place. I'm not sure, probably cheaper.

$200? For a battery? What is that, Canadian?

In any event, rule out alternator problems _first_. All signs point to your having an alternator problem, not a battery problem. Assuming that'* the case, your battery should bounce back as soon as it starts getting a proper charge from the alternator once again.