Battery / Alternator Problem

**cpw006** · 04-04-2010, 11:31 AM

Hello and I am newbie here so bear with me, I am currently having some issues with my battery gauge being in the red and the check gauge light is on. I took the car to Advance and they tested the battery and it tested strong. I asked him about checking the alternator and he said it should be good because the battery tested fine. It pretty much stays between 8 and 13 on the gauge. Since it started this I have been keeping a battery charger on it while its in the garage, but it never reads out of the red on the gauge. I think I am going to take it and have the alternator checked. All the wires seem to be making good contact and are clean.

I guess what I am asking is could it the gauge be reading bad or is it the alternator. If I need to replace the alternator do I need to go with a more powerful alternator as I have a high end stereo with subs and an amp. Thanks for your help with this.

**sunsetorangess** · 04-04-2010, 12:22 PM

Welcome to the party bud....
Ensure your battery connections are good and tight and clean...
Check your connections on your Alt.
If you keep charging your battery your either going to over charge it or burn out of the cells.
The guy at advance is an absolute idiot. Goto a different store and have them run a "charging system check". Most places do it free of charge in hopes of selling you a part. Ie Autozone, Advance, Oreily's etc etc.
Also make sure your Serp belt is in good condition.
You can have batterys that have Voltage but Not Amperage and vice versa.
I have a handheld Tester that works wonders but only if you run the complete test.
Do you have a multimeter?
J

**RyanJM** · 04-04-2010, 06:55 PM

Is your cr an auto and does it have a underdrive pulley. I know if you run a underdrive without the overdrive alt. pulley my voltage was always low especially sitting idleing in d at a red light wth the a/c on at nigh it really dropped. I installed the lt pulley raised the rpms buy 100 and installed a powerbasterds.com 220amp alt. Fits good and looks stock except for the larger wire I installed.

**SandmanWs7** · 04-05-2010, 08:40 AM

I had that problem awhile back. I thought it was the battery at first but it ended up being the alternator. My battery was weak so I took it in for testing and a recharge at my local Autozone. The best way to test your alternator is to turn on the car and disconnect your Negative battery cable. If your alternator is bad the car will turn off.

Changing an alternator is a 2-3 hr job. Have fun, I know I did.

***SMWS6TA*** · 04-05-2010, 11:47 AM

One other thing that no one mention above, our alternators charge between 13-15 volts. If you are below that you are not getting enough charge. A simple rule of thumb is when the battery goes the alternator follows, same thing with the alternator, when it goes the battery will follow.

Something else, if you jump off your car and your PCM reads too low of voltage it will go into "Limp" mode. It idols your car at 3000-4000 rpm. The PCM is trying to kick start your alternator into charging and should only do this for about 2 mins max. If it is to far gone it will high idol until you shut the car off. Don't let it run longer than 3 to 4 mins. You will know your in "limp" mode because it will scare the shit out of you the first time and make you think your car is possess.

Another thing - is your alternator gong bad because it's just old or is it covered in power steering fluid. One a several bad ideas GM did was put the alternator under the PS pump.

When changing the alternator be careful disconnecting the wires.

All of these things above I've had issues with in the last month.

**cpw006** · 04-05-2010, 02:05 PM

Thanks for the advice, I am pretty sure its the alternator. Because if I charge the battery it will still be in the red when I start it up and slowly goes down over a short drive. Last night me and the wife went for about a 30 min drive and it slowly dropped about 1-2 volts in this time. It does not drop fast, I think my alternator may be working a little but not enough to charge the battery good. Am I correct on my thinking here or not. I am planning on changing it sometime this week. The only thing I am not sure on is what amp alternator I need. I do have a pretty large stereo in the car so I am thinking I may need something such as a 220amp....any suggestions and recommendations on which alternator to go with.

**pumpkinman** · 04-05-2010, 02:32 PM

i had the same problem in december the alternator and battery were replaced in october but yet my car would die .. turned out they gave me an alternator for a 6er and thats why it would pass the alternator test and yet it would still drain the charge on the battery

**cpw006** · 04-05-2010, 02:44 PM

Originally Posted by pumpkinman

i had the same problem in december the alternator and battery were replaced in october but yet my car would die .. turned out they gave me an alternator for a 6er and thats why it would pass the alternator test and yet it would still drain the charge on the battery

Did it completely resolve the issue when you got the correct alternator on the car instead of the 6er alternator.

**cpw006** · 04-05-2010, 04:34 PM

Ok so I just went to AutoZone and they checked the alternator and it is for sure bad. That was the most stressful drive hoping I was going to have enough power to get home watching my volts drop, but I made it. I think I am going to go with the alternator Ryan went with unless anyone else has any suggestions. This is the one he recommended:

powerbastards.com

Thanks for the help