97 Taurus Battery Light

my 97 Taurus GL (3.0 Vulcan) has an issue where the battery light will come on anytime I'm heavy on the throttle (IE, passing someone, which is a treat
on this car, i'm used to vehicles with far more pep... should've bought a duratech taurus). It seems once the engine passes about 4000 rpm, the light will flicker and then stay on bright past 4500. Once it's back to cruising rpms, it goes right back out. I checked the voltages both running, and with the engine off, and both seem good (12.6 off, 14.4 running)
Just curious if anyone else has seen this problem, or if it's an early sign either my alternator is going, or my serpentine belt (It looks ok as far as cracking, but i haven't checked it for stretch)
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Teknical wrote:

testing it when gunning it like when the light comes on... if you have a volt meter with long leads you can do it... attach to battery and then close hood... leave the meter inside the car.. then take it for a ride and see what the voltage is when gunning it... probably drops pretty good... might be the belt or might be the pulley or might be the alternator???????
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I debated getting someone to gun the engine in neutral while checking it, however I was afraid that *if* the belt was so-so, it might come off and take out an eye :p... your idea sounds much safer, i'll give that a shot.
Cheers
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Teknical opined in

even safer ... hook the vm to a lighter accessory plug inside the car, would be close enough
I doubt it's the belt, alone.. if it does it at daytime & WOT, the A/C should be off .. the load fairly small and the alt should be still be spinning fast enuff to stay above batt voltage even with belt slip.
I'm thinking brushes/dirty commutator or a bad volt regulator where the fail- safe overvolt circuit shuts the regulator down when it cant control output.
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I was wondering if anyone has found an answer to this problem on the 97 Taurus?. I have a 1996 Nissan 200 and it does exactly the same thing, high RPM and alternator and brake light warning comes on, and goes off after dropping the rpm's. I put belt dressing on the serp belt to no avail. If I get to 50 mph the lights start to flash.
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Ballykeel opined in

Dunno what the connection is with brake lights... but the alt light coming on with high rpm is usually badly worn brushes in the alt.
If you're handy, you may be able to replace them cheaply
--
- Yes, I'm a crusty old geezer curmudgeon.. deal with it! -

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apparently this is a glitch in the Nissan system where when the current from the alt is iffy the two lights go off. It had me confused at first until I learned that bit of technicality. The brake light going off is a red herring. I guess I will go for a rebuilt alt - thanks.
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Ballykeel opined in

like I said, after you see the price you may want to see if NAPA carries the brush set.
It's easy to do on many cars. Google this group to see how i did it on my taurus... the brushes often are on the same assembly as the regulator (small wires). NOT THE RECTIFIER ASSY
--
- Yes, I'm a crusty old geezer curmudgeon.. deal with it! -

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Ballykeel wrote:

$25-40. A bad drivers loss is your gain.
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