Hello, I have a 1993 C4 Corvette.. I just recently discovered a problem. My battery was dead one day so I jumped it, it started up and ran fine. The next day it was dead again so I thought ok, I have a parasitic leak and I checked everything but everything was fine. I jumped the car again and took it for a quick spin.. then parked and turned the car off, I tried starting it again instantly and the battery was dead again. My father told me that my battery or alternator could be dead, but he isnt a mechanic. So before i spend money to replace my alternator and battery I was wondering if anyone on here could please help me out ASAP and maybe give me a diagnosis and some advice. Thanks!

 

Take the battery out and take it to a parts store and have it load tested.

you can do the same thing with the alternator. have it tested.

does your gauge show it charging?

 

sounds like the battery.
If you can jump start it and it runs fine then it is running off the alternator. Since you said if you shut it off and try to restart right away and it is dead that sounds like a battery as well, it wasn't off long enough for any kind of drag to be killing it.

If you have a volt meter I bet if you measure the battery it will be less than 12v with the car off and about 14v with it running.

JMO as I did not stay at a Holiday Inn Express recently !

 

I did last week , and it didn't help at all!!!!!

 

I recently had this problem, take your alternator and have it tested, if its bad, buy a new one. If its fine it might be your battery, have that tested. Its most likely the alternator since it is not starting after you ran it.

 

It takes a long time to fully recharge a battery. You cannot jump a dead battery and drive your car for 15 minutes or so and expect to gain much of a charge. It is no wonder to me that it became dead again in a short time. Whenever you have a dead battery, charge it at least overnight with a battery charger. Also, dead batteries draw a large amount of current at first and this large current heats alternators and shortens their life. Alternators are not made to charge up dead batteries! You may have excess leakage current which discharges your battery. GM says leakage current should not exceed 50 milliamps. My 87 draws 27 ma. and I have no battery problems. You can measure the leakage current with an ammeter in series with the neg battery cable and the neg battery post after the courtesy lights time out.
First things to check are, in the dark look for vanity mirror lights, door map lights, center console lights, underhood lights. Do not leave your key in the ignition because this keeps the anti theft circuit on and will discharge your battery. Do you have a CB, GPS, radar detector, aftermarket alarm, radio or audio amplifier? Check em.
With the ammeter connected, you can pull fuses one at a time while you watch the ammeter and find the circuit that is drawing excess leakage current.

 

Me sure that the dome lights are shutting off.....mine waits 30 seconds to turn them off. (85) There is a timer that can go bad and they might not shut off like they are supposed to.

 

if you want to test your alternator without taking it to the store. start the car up and disconnect the battery. If the car continues to run chances are its not your alternator.

 

So what was the final outcome???

 

Probably got a new battery and doesn't need us anymore.

 

He's too busy driving his vette!

 

 

Or he blew the battery up.

 

Bwah hah hah.... when I read that piece of advice about disconnecting the battery after the engine is running....

The things some people will think up...

 

Blame it on beer.

 

Years ago you might have gotten away with just running on the alternator for a short time shade tree machanics at it's finest

However that was when there were no electronics, circuit boards, or computers in vehicles NO way should anyone try this on a car with a computer in it. The battery maintains constant voltage for the electronics the alternator is just for maintaining the charge back to the battery. Trying to run with out a battery could fry every piece of circuitry in the car I hope the OP didn’t try this. All newer cars will throw a code if battery voltage drops below safe levels.

 

Pulling the cable was a good test for the late 60's early 70's cars. Most of the alternators didn't put out enough power for all of the crap we added later(CB,8track etc.) So if your car was having this issue . if you pulled the cable and it died it was almost always the Alternator.

Even though I have the electronic equipment to check this stuff. I would still pull the cable from my 69 GTX Conv. if I suspected alternator problems.

This is not the way to test an alternator for a 4 wheel rolling computer.

 

CB ........ 8-Track ....... I can almost remember that stuff in my dad's cars !!!

I wouldn't mind seeing a pic of your '69 GTX if ya' got one lying around on your hard drive..... cooooooool car !!!!

 

this is my first picture post , hope it works

 

RLG, that is one sweet looking ride !!!

Thanks for sharing....