Bad alternator or something else?
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Launching!
Joined: Jun 2012
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Bad alternator or something else? 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.
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.
Joined: Nov 2001
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From: Schiller Park, ILL Member: #317
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?
Thread Starter
Launching!
Joined: Jun 2012
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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?).
Last edited by big_g; Jan 31, 2025 at 08:39 PM.
Thread Starter
Launching!
Joined: Jun 2012
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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
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alternate or other issues 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?).