Procharged LM7

starting tonight, I noticed at warmup, my dome light, and headlights started barely dimming and brightening quickly at idle. Not alot, but noticeable. I looked at my volts gauge, and it was fluctuating, too. Normally above 14, around 15, it would dip to 13 and quickly rise again, over and over, kinda quickly. It stopped, then started again, even while driving. Started it again cold, it didn't do it, then did it again after warmed up. I looked at my battery cables and alternator cable, and they were tight.
Is my alternator going or something? It has about 23,500 miles on it. I have a couple amps for the stereo(been in for a couple years), but never a problem like this before today.
Battery always charges ok. I know some of you guys have had failed alternators. Did it do this? I wouldn't think it would fail with the low miles, but who knows, having my amps, and also a supercharger pulling on the pulleys all the time :\ Any ideas? Thanks for any help. Sam

whitez71

It could be battery or alteranator. I saw take it to a battery shop and they will test it for free and tell you what is wrong.

benpimpin1

Hard to tell about the alternator, take it to a shop to test it. The increased load from the amps could easily do it, especially if you play your system with your doors open at idle. The stock alternator is 105 amps, that reading is usually while driving, at idle speeds you are looking at far less current maybe 60 amps, if your truck is only putting out 60 amps and you have over 600 watts in amplifiers then you are overworking your alternator and getting no charge to your battery. Do your amps get hot easily? When an amp is run and does not have adequate power going to it they often times get really hot. Bad news for your amp. This is an easy way to break your system. Stinger has a new 325 amp alternator out specifically for 5.3 and 6.0 silverados, subs, etc. That would be more than you would ever need and you wouldn't ever have to screw with caps, extra batteries etc. The page below is another good alternator builder that has an alternator calculator on it to see exactly what you need.


http://www.h-o-alternators.com/Fomulapage.htm

benpimpin1

were you rpm's on track, or were they dipping also? shouldn't be battery at all, battery is only used to start vehicle and run accessories when car is off. Truck should still run if you disconnect your battery while truck is running if not your screwed.

OBXMarine

iTrader: (2)

I'd do a quick check of your battery terminals. I was experiencing a similar problem the other week and turns out, the battery bolt and extender I have in there weren't as snug as they should've been.

benpimpin1

That is a great thought, you always want to check your connections, spray some corrosion block on them or wire brush them if dirty, do both.

Procharged LM7

rpm's were not changing during the fluctuation. The amps are small. One is a 4X50 Crutchfield(made by PPI) and one is the same but 2X50.
I will have to look more closely when it is light out later on. I was really wondering if some of the guys that have had the alternator go out have seen this?
Lik maybe the internal voltage regulator is goin out, or something.
Thanks for the help so far. Anybody else?

Quik

iTrader: (7)

i have a system containing some high quality ****. i have a 1.5mf cap. use one
of these for your system. its like a second battery for your stereo [kinda]

whitez71

I wouldn't recommend disconnecting your battery while it is running. An alternator use electro magnets that requires dc voltage to operate. Also wouldn't want to risk a voltage spike that could fry the pcm.
.

Black Blown 02

I don't think its your amps or stereo equipment.

Mine does the EXACT same thing. I only have 12,500 miles and its done it for a while now.

If you figure it out, let me know.