Simple question...Maybe??
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Joined: Mar 2001
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From: Pekin, IL
Car: 91 Formula, 79 Trans Am, 72 LeMans
Engine: 305 TPI, 6.6, 350 Pontiac
Transmission: T5, 3 speed, TH350
Simple question...Maybe??
Ok, I think I need a new alternator but I thought I would check to see if it may be something else. When I started the car the voltage fell from 13 to 8 and didnt move while driving, went even lower when I turned on the lights, but they werent that dim. We jumped the car and the voltage did not move up at all? Is this just an alternator or something I am overlooking. Thanks.
Thread Starter
Supreme Member
Joined: Mar 2001
Posts: 1,754
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From: Pekin, IL
Car: 91 Formula, 79 Trans Am, 72 LeMans
Engine: 305 TPI, 6.6, 350 Pontiac
Transmission: T5, 3 speed, TH350
I used the dash one. It said about 8 last night, but today it was about 9 or 10.
It seems like your alternator is bad. You know, the Murrays Auto parts stores in my area has an in-store alternator tester. You just bring in your alternator and an employee puts it in a computerized machine and in about 1 minute the computer will tell you if your alternator is bad. At the store I went to, they tested mine for free.
I was having problems just like you and it turned out I had a bad alternator.
I was having problems just like you and it turned out I had a bad alternator.
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Car: 99 Formula
Engine: LS1
Transmission: T56
Axle/Gears: 342
If the alternator isn't squeeling or loss of any electrical power isn't noticable, sounds like your gauge isn't accurate. Most of them aren't.
Thread Starter
Supreme Member
Joined: Mar 2001
Posts: 1,754
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From: Pekin, IL
Car: 91 Formula, 79 Trans Am, 72 LeMans
Engine: 305 TPI, 6.6, 350 Pontiac
Transmission: T5, 3 speed, TH350
Well, I just went down the street and drove a bit. The car died but I did start it back up, but when i did a belt was squeaking. My friend tested the voltage w/ a guage and it said 11-12 and sometimes went to 8 volts. I'm thinking alternator.
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