Hey guys, I've got 2000 WS6 with 160K miles that I've had for 15 years. The other day I was idling at a stoplight and saw my check gauges light pop on and noticed my battery indicator was in the yellow. Lights flickered on and off as expected, etc. This has been happening randomly for little bursts of time for a couple days now. All my other cars' bad alts in the past have just up and died, while this one is like in limbo? This is the original alternator, so I'm going to replace it with a Powermaster 8242 regardless, but could this be another issue and not just my ancient alternator?

I did check the battery with a voltmeter while idling and it briefly read 0 to 1v (according to my son, who I assume was reading it right. I was in the car watching the gauge) when the battery indicator dropped real low (8v-ish), and showed around 13.9v when idling normal. Seems to happen in gear more than in idle.

 

Could be going bad but check your battery cables and battery also. could be a loose ground cable or bad terminal on the battery.

 

Dead cell in the Battery will do the same. I'd pull that and get it tested.

 

Good suggestions above. If this problem is intermittent as stated, it could certainly still be the alternator, but I'd check the battery cables and test the battery itself before assuming that a new alternator will fix it. How old (and what type) is the battery?

 

The battery is exactly 1 year old (Interstate battery from Costco). The cables were a little loose, but I tightened them and looked for corrosion on the terminals (was none) and the issue is still present. If I were to, say, run my stereo and lights on in Aux mode wouldn't that show if it was a bad battery? (i.e. voltage should be "jumpy" then as well, no?).

 

I just went out and started it back up and now it didn't come out of the yellow at all, and check gauge light is on. I tested the voltage and it was like 11. Also, I think I hear a "grinding" noise while it is idling, which I suspect is the Alt. bearings, yeah?

 

pull the belt and spin each pulley by hand. they should all turn smoothly and quietly. if you have a bad bearing it will feel rough and sometimes squeak depending on how bad it is. also if you can get it to a parts store they will check the alternator and battery for free

 

Get a 145 amp truck alternator and discard the extra bracket mount.

 

Hello I imagine You've figured out what's up with the charging issue by now. If You have a decent battery charger put that on the battery after checking the distilled water/sulfuric acid level for 5 minutes then check the voltage and if good it should read at least 12.7-12.85volts .If at that voltage then battery if good. I would say the most common charging issue is the large positive charge wire bolted to the back of the alternate that goes directly to battery positive or that wires connection to the alternate. The grounds are certainly a possibility as well as the alt mounting bolts to bracket. 4th gen Camaros and firebirds alt location being down low could lose ground from oil and water over time. If there is any metal debris or if water gets inside alt enough that could touch rotor and stator at same time can cause intermittent output but usually when that happens it will kill the voltage regulator instantly which renders the alt non-functional. If You have a powerfully stereo amp then yes a 145 amp truck alt is a good idea. Buy a good used 1 for roughly $50 and have it tested. Good luck