I'm looking for some input before I start tearing into my s14 in the morning.

Background:
97 ka, stock electrically except for an optima yellow top, and my stereo.

The battery came outta my GTO, and the terminals are on the opposite side...meaning the hot lead is a bit tighter than I would like it.

A few months back the brake light and battery light came on on the way to work (my understanding is this is an indication of a failing alternator, or wiring issue) it was rpm dependent, meaning the light went away after accelerating.
But after checking the wiring to the alternator, and letting the car sit for a night, it went away....no trouble codes our anything since.

Earlier this week I meet up with sDaigle, and noticed a wine or whistle, that I thought was a bearing, either the alt, carrier, or something in the tranny. I joked with some friends that if it was the alt, id know sooner rather than later

This morning, I noticed that my music was skipping, only it was playing off a thumb drive. The volume on the radio then cut out. A minute or two later, the radio started turning off and on of its own accord. At this point I was at work.

It sat for a few hours, when I went to leave, it would start, but not idle...which it has never done. I manually manipulated the throttle, got it going, and headed to my last meeting. The radio issue presented in the same way, in the same order...skipping, volume, power. Once I parked at my destination it refused to start again. I can hear the starter solenoid firing, but there's not enough juice to turn it over.

Im going to start with the alt, battery in the morning, but wanted to see if anyone else ever had the same radio issue. The radio harness is wired properly, and the subs/amp all have the proper cables, fuses, grounds and whatnot.

Any thoughts?

Finally tracked down the issue, it only took a month.

Combination of a bad battery and a bad alternator - both of which were tested at autozone and came back as passed on their bench test machine. Do not take their readings at face value, as their machine does not put anywhere near enough load into either.
The failure I described initially was the alternator not recharging the battery. My system would then put a decent drain on the battery until the volatge got low enough to trigger the auto shut off on my head unit (pioneer safety feature per their Customer service). Once the head unit was off, the amp would shut off, and now the crappy alternator would start pumping valtage back to the battery.

As soon as it crossed the 10-11 Volt threshold, the radio would try to turnback on...but the voltage would quickly drop and so on and so forth...which is where the weird behavaior was coming from.

Meanwhile the fact that there was so much draw in the optima yellow top shortened its life drastically. Based on some recent reviews, there are a lot of people having life issues with optimas in general, and I will be looking for somthing a bit more durable down the road.

Result,

I now have a new yellow top (it was under warranty), and a new alternator - and my mechanic confirmed no other shorts in the system...I know that most 240 guys hate traditional shops, but mine speciallizes in electrical, and they are damn good, only took them an hour to troubleshoot the charging circuit, body and main harness to confirm that there was no other shorts.

Hi,
I read through your thread here. I sounds like the alternator wasn't able to keep up with your system demands. The fact that once you turned the stereo off and the alternator began charging the battery leads me to think this. Do you know what the voltage output was on the YellowTop before charging? Did they properly recharge the YellowTop before they replaced it. If they did what was the output at that point and what was the reason the replaced it. All is good if you got a new battery but you probably just needed a proper recharge. You said in your post that the battery was in the low 11 volt range and just so you know 11.2 volts is considered 100% discharged so you were certainly right near that point. I would love to get my hands on that battery and see how long it would last now that it was considered used up. With the new alternator you should be fine now, just be sure and keep a close eye on it for a while.
Thanks,
Bill Howell
eCare Manager, OPTIMA Batteries, Inc.

I assume they properly recharged it the first time. I did not see the display on the screen, but the parts guy spent 20 minutes grumbling looking for the proper machine. He threw around a bunch of acronyms that I've never heard, but when I started to ask questions, he started talking about how the glass pack /gel batteries couldn't go on the normal charger.

Again, from context I assume he put it on the right machine - but it was in the back of the store, and I couldn't go behind the counter.

The second time it was dead, it was 2 different sales reps, and as soon as they saw me they sort of chuckled to themselves and said something to the effect of, "We got another dead optima," like they had seen a glut of dead ones lately.

This time I did not hang around in the store to see them test/charge it. I found out a few hours later when I called back that it was not re-chargeable. I only went back to pick up my new yellow top because the old one was still under warranty.

With the alternator repair, the car has been running great, and even the stereo sounds better. I still like the optima dry cells, and will def be giving them another shot in the future...If anything I killed this one a bit too soon.