Bad battery or alternator??
Bad battery or alternator?? Let's start back on July 4th...
I drove down to the car lot to check out my 2001 SS. When I tried to fire it up the battery only had enough juice to "click" the starter. After sitting on a battery charger for several minutes, it fired right up and drove fine.
Fast forward to today...
I haven't had any issues with the voltage just driving around. But today I installed the SLP skip shift eliminator. I understand why GM put that feature in the car, but good Lord is that annoying! Anyway, I disconnected the battery per the instructions. When I got everything back together I fired it up to drive over to AutoZone and pick up a light bulb. I knew right away that something was different. The idle was way low as was the voltage gauge. I drove through the development and when I came to a stop sign it died. It fired right back up, but the volts were still low. I ran the rpms higher for the rest of the trip to AutoZone thinking that may help charge the battery which was fine before I disconnected it. When I left AutoZone everything seemed normal.
Is this a sign that the battery or alternator may be dieing?
I also noticed that the car revs a bit easier now as if someone was running cheaper gas and the engine was retarding itself. Of course, it did spend a good deal of its life just sitting around waiting for someone to drive it so who knows...
I drove down to the car lot to check out my 2001 SS. When I tried to fire it up the battery only had enough juice to "click" the starter. After sitting on a battery charger for several minutes, it fired right up and drove fine.
Fast forward to today...
I haven't had any issues with the voltage just driving around. But today I installed the SLP skip shift eliminator. I understand why GM put that feature in the car, but good Lord is that annoying! Anyway, I disconnected the battery per the instructions. When I got everything back together I fired it up to drive over to AutoZone and pick up a light bulb. I knew right away that something was different. The idle was way low as was the voltage gauge. I drove through the development and when I came to a stop sign it died. It fired right back up, but the volts were still low. I ran the rpms higher for the rest of the trip to AutoZone thinking that may help charge the battery which was fine before I disconnected it. When I left AutoZone everything seemed normal.
Is this a sign that the battery or alternator may be dieing?
I also noticed that the car revs a bit easier now as if someone was running cheaper gas and the engine was retarding itself. Of course, it did spend a good deal of its life just sitting around waiting for someone to drive it so who knows...
What were the volts when you had the engine running? The easiest thing to do is to just take it to AutoZone and have them test the battery/alternator for you.
It sounds to me like it's more of an alternator problem than a battery problem, but going to need some more info.
Try turning on your lights, or just the interior lights. Do they dim over time? Do they brighten up as the RPMs increase?
It sounds to me like it's more of an alternator problem than a battery problem, but going to need some more info.
Try turning on your lights, or just the interior lights. Do they dim over time? Do they brighten up as the RPMs increase?
I agree that it sounds like the alternator. One way to tell if its the alternator is to start it up and disconnect the battery, if it dies then the alternator is bad. That's old school style; just get to autozone and have them tell you.
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Joined: Nov 2010
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If the problem is intermittent, its likely the battery. Without a bracket to hold it down, constant jostling and vibration will make the lead plates inside the battery come loose and then randomly reposition back to normal.
You find yourself dead in a parking lot one day... get a jump or charge the battery, and everything is fine for a couple weeks. Meter looks fine, etc.
Then one day, it happens again with no symptoms leading up it. Been there, done that. Got a new battery and a simple metal bracket fabbed to hold the battery down snugly, problem disappeared. Most drag strips have rules about having your battery secured for fire reasons, so if you ever want to take your car to the strip, its good to have it done anyways.
If it happens again, you can take the battery out and GENTLY rap it with a big stick or the asphalt, just enough to try to jar the innards. If your voltage magically goes back to near normal, then you know what the problem is.
You find yourself dead in a parking lot one day... get a jump or charge the battery, and everything is fine for a couple weeks. Meter looks fine, etc.
Then one day, it happens again with no symptoms leading up it. Been there, done that. Got a new battery and a simple metal bracket fabbed to hold the battery down snugly, problem disappeared. Most drag strips have rules about having your battery secured for fire reasons, so if you ever want to take your car to the strip, its good to have it done anyways.
If it happens again, you can take the battery out and GENTLY rap it with a big stick or the asphalt, just enough to try to jar the innards. If your voltage magically goes back to near normal, then you know what the problem is.
Last edited by Capricio; Jul 14, 2011 at 08:32 AM.
