Losing voltage

untamed351 · 07-29-2001, 08:50 AM

my 85 is not holding its charge andd i tring to figure out why. when im driving the guage sits at a hair above 14 volts as soon as i shut it off its goes down to a little under 12 volts. The battery was replaced 2 weeks ago. Before that everything was fine. Could it be the battery is bad or could it be the external voltage regulater?or the alternator?

RMARIANI · 07-29-2001, 09:02 AM

I went through this a few months ago. I'm assuming that since you replaced your battery two weeks ago, you were already having problems with your charging system. We all want to believe its always as simple as buying a new battery. I would bet its your alternator. Be careful though, I bought my new, not rebuilt, alternator at Pep Boys and it was a dud. They replaced it, without a question, but they couldn't replace the time I wasted installing and removing it. Good luck.

untamed351 · 07-29-2001, 09:09 AM

i wasnt having any problems with the charing system. Since i bought the car last year it had a cheap no name battery in it. never died, never lost charge, but i bought a new one to be safe. The alt was the first thing i repalaced when i bought the car. I upped to a 130 amp alternator

dinomite · 07-29-2001, 11:42 AM

i don't understand your problem, cause you say that witht the car on (running) that it is at 14 volts, which is the normal charging voltage. you went on to say that when you turn it off, that it is at 12 volts. its a 12 volt battery, so it should be at about 12 volts, so that is normal too. whats the problem?

untamed351 · 07-29-2001, 03:25 PM

when i was driving at normal speeds it read 14 volts when i came to a light it would drop to 11-12 volts. When the car sat overnight the guage read 10 volts.
i had the battery and alternator tested. Ends up the alt was bad. Charging was erratic. All fixed now. Thanks

dinomite · 07-30-2001, 12:31 AM

oh, ok. even if the alt is bad, the battery should read 12 volts all the time. check it with the car OFF completely, if it doesn't read 12 volts (you said it read 10) then it is moste definently bad.

------------------
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07-29-2001, 08:50 AM	#1
untamed351 Registered Member Join Date: Jun 2001 Location: Belmar, NJ Posts: 52	Losing voltage my 85 is not holding its charge andd i tring to figure out why. when im driving the guage sits at a hair above 14 volts as soon as i shut it off its goes down to a little under 12 volts. The battery was replaced 2 weeks ago. Before that everything was fine. Could it be the battery is bad or could it be the external voltage regulater?or the alternator?

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07-29-2001, 09:02 AM	#2
RMARIANI Registered Member Join Date: Apr 2000 Location: New Jersey Posts: 167	I went through this a few months ago. I'm assuming that since you replaced your battery two weeks ago, you were already having problems with your charging system. We all want to believe its always as simple as buying a new battery. I would bet its your alternator. Be careful though, I bought my new, not rebuilt, alternator at Pep Boys and it was a dud. They replaced it, without a question, but they couldn't replace the time I wasted installing and removing it. Good luck.

07-29-2001, 09:09 AM	#3
untamed351 Registered Member Join Date: Jun 2001 Location: Belmar, NJ Posts: 52	i wasnt having any problems with the charing system. Since i bought the car last year it had a cheap no name battery in it. never died, never lost charge, but i bought a new one to be safe. The alt was the first thing i repalaced when i bought the car. I upped to a 130 amp alternator

07-29-2001, 11:42 AM	#4
dinomite The Dude Join Date: Feb 2001 Location: Arlington, VA Posts: 1,262	i don't understand your problem, cause you say that witht the car on (running) that it is at 14 volts, which is the normal charging voltage. you went on to say that when you turn it off, that it is at 12 volts. its a 12 volt battery, so it should be at about 12 volts, so that is normal too. whats the problem?

07-29-2001, 03:25 PM	#5
untamed351 Registered Member Join Date: Jun 2001 Location: Belmar, NJ Posts: 52	when i was driving at normal speeds it read 14 volts when i came to a light it would drop to 11-12 volts. When the car sat overnight the guage read 10 volts. i had the battery and alternator tested. Ends up the alt was bad. Charging was erratic. All fixed now. Thanks

07-30-2001, 12:31 AM	#6
dinomite The Dude Join Date: Feb 2001 Location: Arlington, VA Posts: 1,262	oh, ok. even if the alt is bad, the battery should read 12 volts all the time. check it with the car OFF completely, if it doesn't read 12 volts (you said it read 10) then it is moste definently bad. ------------------ 90LX AOD Convertable: Lakewood control arms, FMS springs. Best 1/4: 15.277@92.25 (2.27 60') AIM: dinomite1, roadracestang dinomite@softhome.net