Hi guys it's great to have thirdgen back. Any way I went out to try and start the IROC and I get nothing. I drove it earlier today and had no problems. The starter and alternator were replaced last year so I'm thinking battery. When I turn the key I get no ticks at all. The fan engages and the volts on the dash read about 10 but I get nothing. It has been starting kind of hard for a couple of weeks and I noticed yesterday my voltage was dropping with each blink of my turn signal while at a light yesterday with my lights on. Any ideas or suggetsion?

 

Got a voltmeter? Put it on the batt. posts if you do. A dead (or nearly dead battery)can still make some of your accessories (i.e. fan) work. Try charging the battery overnite and then see what it does. If the car will start, then take your voltmeter while its running and check voltage at the battery, it might put out upwards of 14.5 V if your battery is low. If lower then 12.5 or so, then you probably have a charging system problem..
Definately sounds like a dead battery if Volts are around 10 tho....
If you don't have a voltmeter, take the battery to somewhere like auto zone or advance and they can test it for you. A load test is more reliable anyways..

[This message has been edited by MikeC.86Roc (edited September 13, 2000).]

 

Like Mike said, you should charge the battery first to determine if it is the battery that is bad (won't accept a charge), or the charging system that is bad.

To charge a dead or nearly-dead battery with the alternator will take a long time. Best to charge "out of the vehicle" to ensure that it is fully charged.

If the battery is bad, it won't accept the charge, so you'll just need a new battery. If it is good, suspect the alternator.

The in-dash voltmeter is not very accurate, expecially at the limits. A digital voltmeter (DMM) would be better. That said, 10 volts is very low. A good battery will show about 12.6-12.8 volts without a heavy load. A battery will show a higher than normal voltage immediately after charging, known as "surface charge", which is why you'll see 13+ volts after removing the charging current (or turning the car "off"). To remove this "surface charge", (1)wait a couple hours, (2) turn the headlights on "high beam" for five minutes and then wait five minutes, or (3) with a battery load tester, apply a load at one half the battery's CCA rating for 15 seconds and then wait five minutes.

A battery with 12.65+ volts will be at 100% charge (1.265+ specific gravity). 12.45 volts is 75%, 12.24 volts is 50%, 12.06 is 25% and 11.89 is 0% state of charge. These figures presume the electrolyte is above 70°F. add 0.012 volts (12 millivolts) per degree below 70°.

When cranking, you should see over 10.0-10.5 volts.

From the above, you can see the importance of an accurate digital voltmeter ($20-250, $85-100 is typical for a good (better than 0.5%) DMM).

Since you didn't hear the solenoid clicking when trying to crank, it's very possible you had several volts less than 10.

Another possibility is a bad connection at the battery and/or starter solenoid, but batterys are more likely to go bad, especially since side post battery's are less likely to have a bad connection than top post.