Today I was driving up a really steep hill and had my AC blasting and my stereo system (2 amps etc.) turned up pretty loud. Then the battery gauge on my dash starts to drop and now I get a whine coming from the alternator. The gauge goes up to normal at higher RPM's but drops down at idle. Is my alternator fried. I'm going to pull it tomorrow and have it tested. What do you guys think?

 

Not fried... It either is on or off. If it shows a low voltage under those conditions, then it is stock. A new (stock) one will do the same thing.

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1984 z28 w/ a 357 cu in. monster engine which is looking like the posterchild for Edelbrock with the exception of the Holley 750vac... all the suspension stuff... 9-bolt posi disk is in...

-=ICON Motorsports=-

 

What he said, and I would have the battery checked. I big stereo will pull more juice than an alternator can put out, resulting in pulling juice from the battery--especially at idle. This will cause the voltage to drop and really work the alternator until the battery is recharged. With a big stereo system, get the biggest battery you can fit--a better alternator will help as well.


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350 with stealth intake, holley carb, 470 lift cam. 700r4 with .5 boost valve, vette servo, tci lock-up kit, B&M megashifter. Richmond 3.73 gears, powertrax locker, timkin bearings, synthetic lube. Custom 3 inch single into 2 2.5 pipes. 1 1/2 drop springs, 1 5/16 solid front sway bar, 1 inch rear bar, custom subframe connectors, custom LCA relocation brackets. Kobel ground FX, current red metallic paint. Lots of other stuff...
82camaro