02 LS V8 Charging issue. Alternator maybe?

[2k2ls]

So recently the LS has been making a deep whining noise on startup. This morning it died on the side of the road. I gave it a jump and it started right up but the ABS light was on and the dash lights were dimming out. I have a capacitor in the back for my sub and it was reading less than 10V when the car was shut off. When running on its own it was in the 12-13 range but would degrade rather quickly to the point the windows wouldn't roll down (even thought the motor was running) I removed the battery and gave it a test and under load it still gave me 12 volts. Is it safe to say the alternator is shot? Just wondering if anyone experienced anything similar or had additional trouble shooting advice. Thanks in advance.

 

[joegr]

It is probably the alternator, but the wiring to the alternator could cause issues like yours as well.

 

[2k2ls]

yea Im assuming (shouldnt assume) that it is. I remember seeing in a thread someone mentioning the wiring so I'll definitely start by inspecting that.

 

[2k2ls]

well since sooo many people offered to help I figured I'd update.

The issue was indeed the alternator. For anyone experiencing a loud, low-tone whining when their car starts up, you may want to look at the alternator as well. Not only is the car charging without a problem but its way quieter on a cold start and while driving its quieter. Also, my HID's used to flicker and were getting worse yet revving the engine would make it stop. I'm guessing a low output would cause this because that problem is gone as well. Hopefully someone who has similar problems may be able to use this thread to problem solve.

Thanks joegr for the reply.

 

[Fred G]

umm if you have a system you may want to upgrade your alt to a high output especially with a cap in the back. If I remember correctly the stock alt is only 120 amps.

 

[2k2ls]

Yea I used to have 3 12"s crammed back there, now its just 1 10" but I kept the cap since it doubles as a gauge. But its funny you mention that because I had an alternator go years ago when I first picked it up but it was under warranty and my buddy at the audio shop said the same thing about an upgrade. Thanks!