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Old 07-08-2003, 04:31 AM   #1
Low87on20s
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Question Electrical Question?

Ok, here's the story... While driving into work this morning my amp guage suddenly spikes from @14 all the way into the red to the 18. It did this once or twice real quick. Then about 5 minutes later, it spiked for about 10 seconds. It did this with my a/c on full, bright lights on, radio on, etc. Everything got brighter and my a/c fan started blowing harder!

What causes electrical spikes like this? Is my alternator going bad?
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Old 07-08-2003, 11:51 AM   #2
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TTT

anyone ever experience this?
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Old 07-08-2003, 12:27 PM   #3
the baron
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I have ni idea if the voltage regulation happens inside the alternator or in a separate box.
What I remember from school ( a looong while ago...) is that a over voltage is very dangerous to the electric devices , you could kill your battery...

So , fix it ASAP

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Old 07-08-2003, 12:30 PM   #4
Low87on20s
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Thanks. I am concerned about the dangers of a spike because I still need to drive it 20 or so miles home from work. I guess if I see it spike, the only thing I can do is turn it off.
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Old 07-08-2003, 12:33 PM   #5
swervin ervin
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I'm no electrical guru for sure, but if I were guessing, I'd say the internal voltage regulator may be going bad. I would pull the alternator and have it tested. But, unless it spikes while testing, it may not show up.
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Old 07-08-2003, 03:33 PM   #6
rockman20
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Definitely sounds like the regulator. Spikes are bad. Electronics do not like em. Hence why computers want surge protectors on them.

If you feel comfortable tearing an alt. apart, you can buy the regulator for it and replace it yourself. It's not that hard. Trickiest part is getting the bushings in their holder and sticking a pin in there to hold them.
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Old 07-08-2003, 04:53 PM   #7
apstguy
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Alternators produce AC but have converters to change to DC, so when they go bad evil things happen to your electrical system. Replace your alternator or regulator!
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Old 07-09-2003, 09:00 AM   #8
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Well, I made it home yesterday and it spiked off and on all the way. The last two miles, it pegged at 18. I had to pull over and cut the truck off about 5 times in those last two miles. I pulled the alternator and luckily it was still under warranty. I had replaced it last July 22 when I replaced the battery and all the cables.

Everything is grand now. I appreciate everyone's input.
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