Battery or alternator ??
Thread Starter
Pro
Joined: Mar 2006
Posts: 691
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From: Wayne NJ
Battery or alternator ??
While waiting online for inspection, I was noticing my volts going slowley down,my A/C was on, so was my radio,yes the car was idling fine.Then my radio lost power,then the dash started to fade,I looked at the volts, it read 9.2,the guy told me to shut off the car
,well, it didn't start. My alternator is about 1 1/2 yrs old,very few miles on it. My car has been in the shop for a little over a week and they needed to charge the battery because I guess leaving the hood up drained it,it is also a year+ old. how long should I charge it for and how can I tell if its the alternator or was the battery drained to low for it to hold a charge
,well, it didn't start. My alternator is about 1 1/2 yrs old,very few miles on it. My car has been in the shop for a little over a week and they needed to charge the battery because I guess leaving the hood up drained it,it is also a year+ old. how long should I charge it for and how can I tell if its the alternator or was the battery drained to low for it to hold a charge
Instructor
Joined: Aug 2007
Posts: 151
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From: Mesquite Tx
I don't know which one it could be but I recently took my Chevy Tahoe that was not wanting to start to Autozone and they tested the battery right there while it was still in the vehicle. Sure enough, the battery had a bad cell. I bought a new duralast and all is good. Make sure you watch em though, so they don't try to tell you it's bad when it's not.
Pro
Joined: Aug 2005
Posts: 630
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From: BEMIDJI MN
The same thing happened to me. First the radio went crazy, then about 2 minutes later the dash started to flicker. It was the alternator. You can remove it and take it in to Auto Value and have it bench tested for free. It only took a couple of minutes to put the new one in and I was good to go.
Your volt meter should be registering around 14 volts. If not it is probably the alternator.
Your volt meter should be registering around 14 volts. If not it is probably the alternator.
Last edited by Billy Stargazer; Sep 17, 2008 at 06:30 PM. Reason: forgot to add something
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
I would pull the battery, have it fully charged and tested for cranking Amp capability.
If it fails and assuming connections are in good condition, the alt would be the item to replace.
If it fails and assuming connections are in good condition, the alt would be the item to replace.
Drifting
Joined: Nov 2006
Posts: 1,791
Likes: 3
From: Maine
I replaced my alternator only to find out it was a corroded battery cable connection to the battery terminal causing my voltage problems. Check your connections in the charging system first. Charge the battery overnight with a tender and see if it still does it. Then have the alternator tested.
When I went through this I found out I still have the original AC Delco battery that came with the car in 1995. It is a 6 year battery and still works great 13 years later.
When I went through this I found out I still have the original AC Delco battery that came with the car in 1995. It is a 6 year battery and still works great 13 years later.
Le Mans Master
Joined: Dec 2002
Posts: 6,715
Likes: 2
From: Santa Teresa New Mexico
This is a really basic repair..........chk the battery........if good.......chk the alternator.
A basic volt meter will do the job.........no voltage out of the alt......no charge to the battery......... alt...............charge to the battery.......bad battery or cables.
If you maintain your car you'll have very few problems.
The majority of problems with cars is the owner operator................
A basic volt meter will do the job.........no voltage out of the alt......no charge to the battery......... alt...............charge to the battery.......bad battery or cables.
If you maintain your car you'll have very few problems.
The majority of problems with cars is the owner operator................
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From: So. Cal.
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volts
My experience with 88-89 altenators they can be damaged very easy. They are sensitive to jumping and charging the batt. or car. I would get a known good batt. and see how the car charges with the car running. A "Fast" charge by your mechanics done improperly could have possibly over charged your batt. and damaged your alt..... my .02$
Thread Starter
Pro
Joined: Mar 2006
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From: Wayne NJ
This is a really basic repair..........chk the battery........if good.......chk the alternator.
A basic volt meter will do the job.........no voltage out of the alt......no charge to the battery......... alt...............charge to the battery.......bad battery or cables.
If you maintain your car you'll have very few problems.
The majority of problems with cars is the owner operator................
A basic volt meter will do the job.........no voltage out of the alt......no charge to the battery......... alt...............charge to the battery.......bad battery or cables.
If you maintain your car you'll have very few problems.
The majority of problems with cars is the owner operator................
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Thread Starter
Pro
Joined: Mar 2006
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From: Wayne NJ
My experience with 88-89 altenators they can be damaged very easy. They are sensitive to jumping and charging the batt. or car. I would get a known good batt. and see how the car charges with the car running. A "Fast" charge by your mechanics done improperly could have possibly over charged your batt. and damaged your alt..... my .02$
the battery is a Interstate megatron II sold at my local ETD service center. I think it was about $90. Ill start with a new battery tomorrow and go from there. However I was just in the garage and she started right up and the volts read 12.7 with the car in drive.But I did notice a weird noise coming from the air pump just above the alternator,or it might be the alternator. I remember when it went the last time it was a high pitch grinding noise.
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batt.
On the alt. like you have, its easy to "cook" diodes. Car will run fine for a few days bsfore you notice anything.
I have 2 rules regarding my 89 vert.
1) I NEVER jump another car from my vette. The start up surge from other car can damage alt. Takes a few days for car to run batt down. Ask me how I know.........
2) I NEVER "FAST" charge a batt. Very hard on batt.
Just cause your batt is only 1 year old dont mean anything, IMHO. Check water level also.
I have 2 rules regarding my 89 vert.
1) I NEVER jump another car from my vette. The start up surge from other car can damage alt. Takes a few days for car to run batt down. Ask me how I know.........
2) I NEVER "FAST" charge a batt. Very hard on batt.
Just cause your batt is only 1 year old dont mean anything, IMHO. Check water level also.
Melting Slicks
Joined: Dec 2004
Posts: 2,954
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From: Obama=death for America
Some of you may not like what I'm about to say, but here goes anyway. I can't stand Interstate batteries. That doesn't mean yours is bad. It just means that it wouldn't be in my car. Like it was stated, charge it (slowly) and take it to Autozone. They'll check it for free. They'll also check your alt. for free. Your problem could be neither of these two. It could be something as simple as a loose battery cable.
Le Mans Master
Joined: Dec 2002
Posts: 6,715
Likes: 2
From: Santa Teresa New Mexico
the battery is a Interstate megatron II sold at my local ETD service center. I think it was about $90. Ill start with a new battery tomorrow and go from there. However I was just in the garage and she started right up and the volts read 12.7 with the car in drive.But I did notice a weird noise coming from the air pump just above the alternator,or it might be the alternator. I remember when it went the last time it was a high pitch grinding noise.
Heel & Toe
Joined: May 2006
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My fathers vehicle is a 2002 Bravada. It stalled just like your Vette, and they took it in,and they couldnt find 1 thing wrong. To reduce price on gas they added water, and that water messes with the system. Its probably not anything wrong with your car, switch gas maybe. good luck
Racer
Joined: Apr 2007
Posts: 336
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From: Pine Colorado
I was curious about my C4's charging system since I had some flicker on my dash even with a new battery, so I took the car to Checker and they tested the alternator on the car; it was fine. Finally found a bad terminal screw on the negative side cable that would jiggle and loose contact when on or after a run on a bumpy road. Replaced it and now have no problems.
Thread Starter
Pro
Joined: Mar 2006
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From: Wayne NJ
My fathers vehicle is a 2002 Bravada. It stalled just like your Vette, and they took it in,and they couldnt find 1 thing wrong. To reduce price on gas they added water, and that water messes with the system. Its probably not anything wrong with your car, switch gas maybe. good luck
Melting Slicks
Joined: Feb 2008
Posts: 3,286
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From: Palm Beach
My fathers vehicle is a 2002 Bravada. It stalled just like your Vette, and they took it in,and they couldnt find 1 thing wrong. To reduce price on gas they added water, and that water messes with the system. Its probably not anything wrong with your car, switch gas maybe. good luck
Race Director
Joined: Jun 1999
Posts: 14,924
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From: Merritt Ils Fl
Before you start throwing money at it why not take it to either Autozone or Advance. Either can check the basic condition and operating function of both the alternator and battery as installed. May not be the very best testing on the planet but it works.
Drifting
Joined: Nov 2006
Posts: 1,791
Likes: 3
From: Maine
the battery is a Interstate megatron II sold at my local ETD service center. I think it was about $90. Ill start with a new battery tomorrow and go from there. However I was just in the garage and she started right up and the volts read 12.7 with the car in drive.But I did notice a weird noise coming from the air pump just above the alternator,or it might be the alternator. I remember when it went the last time it was a high pitch grinding noise.