alternator voltage drops when car gets hot
#1
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Car: 1984 Camaro Z28
Engine: 350 from an elcamino
Transmission: stock t-5
Axle/Gears: 10 bolt 3.73 limited slip
alternator voltage drops when car gets hot
The voltage on my 1984 z28 with a 350 and a t5 drops when the car reaches operating temp. Itll be about 13-14 when I first start the car, and then it will drop to just over 12 and dips when the headlights are put on. The alternator is a rebuilt one. The last one had the same problem but worse. I thought it was the alternator ubt now im tihnking the grounds. Any ideas?
#2
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Car: 1989 Camaro RS
Engine: 305 V8
Transmission: Auto
Re: alternator voltage drops when car gets hot
well if the issue only happens after the car reaches operating temp im assuming for some reason to much heat is hitting the alt and messing with it that way some how you could try heat shielding your exhaust and see if that helps
#3
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Car: 1984 Camaro Z28
Engine: 350 from an elcamino
Transmission: stock t-5
Axle/Gears: 10 bolt 3.73 limited slip
Re: alternator voltage drops when car gets hot
Im tihnking aobut that too. The car is running stock manifolds, and pipes though. Thats why I didnt think of that right away.
#4
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Engine: 355
Transmission: 700r4
Axle/Gears: 3.73 Trutrac
Re: alternator voltage drops when car gets hot
Is this problem causing any problems such as the engine missing?
#5
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Car: 1984 Camaro Z28
Engine: 350 from an elcamino
Transmission: stock t-5
Axle/Gears: 10 bolt 3.73 limited slip
Re: alternator voltage drops when car gets hot
No other problems really. I am looking to go to a dual fan setup becuase the car runs hot on the highway sometimes. The engine runs pretty well otherwise. The reason I'm thinking the grounds is that when you go to do something with the car off( put up the windows, leave the lgihts on for a sec.) the voltage drops a lot. If I remember correctly the voltage shouldn't drop that much, but maybe I'm wrong.
#6
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Car: 1984 Camaro Z28
Engine: 350 from an elcamino
Transmission: stock t-5
Axle/Gears: 10 bolt 3.73 limited slip
Re: alternator voltage drops when car gets hot
The problem occured again. The car was a bit low on coolant, but i know where the leak is. The voltage dropped to like 10 on the factory gauge when the lights were put on while I was on my way home. I just had my low beams on. The car didn'ty die, and would come back to like 13 when the lights were turned off. Could this just be the factory gauge, or the wiring to or from? I have no idea if the wiring on this car was touched, or how it would have been touched.
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#8
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Car: '91 RS Camaro
Engine: 5.0 TBI
Transmission: Manual
Axle/Gears: 3.08
Re: alternator voltage drops when car gets hot
Check your ground - Block to Firewall
Ive had this issue as well. Most likely a ground and that one is most common in my experince...
Ive had this issue as well. Most likely a ground and that one is most common in my experince...
#9
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Car: 1988 GTA
Engine: 5.0 TPI
Transmission: T5
Axle/Gears: 9 Bolt, 3.45
Re: alternator voltage drops when car gets hot
It could also mean the alternator is on it's way out. I had 2 different reman (duralast gold) ones die within a week. Both times, before they failed, the voltage would begin to slowly drop.
#10
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Car: 1982 Trans am
Engine: 383
Transmission: AGE M22Z
Axle/Gears: Moser 9" 3.70 detroit locker
Re: alternator voltage drops when car gets hot
Check your block to firewall ground and the negative battery cable make sure its tight on the battery and were ever its grounded to. It probably just a bad ground and maybe the gauge, my factory gauge is always all over the place.
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