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Problem w/ battery or is it something else?

Old Dec 9, 2004 | 09:00 AM
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Default Problem w/ battery or is it something else?

These were posted on another site by me:

Posted 12/2/04
Last night, I went to pick up my wife from work. I put the key into the ignition and turn. The truck didn't seem to want to start but did. I turn the truck off to see if it will do it again. It did. I am starting to wonder what is going on. I still take the truck to go pick up my wife. As I get to a light and start to stop I notice my voltage gauge drop and come back up again. It was kind of strange bacuse I have never seen it do that before. Well I get to my wife's work and I stop and my voltage gauge does it again. What does that sound like to you? Battery? Alternator? Something else?
Posted 12/9/04
Well, I finally was able to go to AutoZone last night and get my battery and alternator tested. Everything checked out fine. I even looked at the bettery connection and it showed no corrosion. What Hanr2 posted is still lingering in the back of my mind. Something is still going on with my electrical system. On my way to work this morning the voltage meter went down to half way between 9 and 14 volts.

If my battery is bad, what red top optima would I need to get? When I was at Autozone, they had two different red tops. One was priced at $110 and the other was priced at $120. I don't remember what the part numbers were.
Anybody else experience problems like this?
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Old Dec 9, 2004 | 09:16 AM
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Sounds like a charging problem to me...

With the truck running, you should see at least 13.5 to 14 volts on the gauge (or across the battery terminals). If you don't you're not getting a charge out of the alternator.

With the truck off, you should see at least 12 volts.... but not really any more than 12.3 or so. If you don't that's a pretty good indication that the battery is weak. The sure-fire way to test that though, is to do the load-test that autozone probably did for you.

If you're battery gauge was reading normal at the time, then the alternator test that AZ did would most likely come back as 'ok'.

Unfortunately electrical problems like that are either "go" or "no go". You have to catch them when they're not working to really diagnose them...
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Old Dec 9, 2004 | 09:21 AM
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When the truck is running the gauge shows either at 14 or slightly below. I thought that it was suppose to be above the 14 mark? I will check during my lunch break to see what the gauge reads w/o the truck on.
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Old Dec 9, 2004 | 09:35 AM
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I had problems on my 2000 of the same sort. Never had problems starting but the voltage would drop quite often. Pretty positive it was my voltage regulator but the dealer never could find anything wrong with it. The Gauge would dip to around 12 or so and the headlights would dim. I was running aftermarket PIAA bulbs in my headlights at the time and it started blowing them due to low voltage.
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Old Dec 9, 2004 | 09:36 AM
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Mine is always around 15-16. That is a weird problem. Do you have trouble with lights or is it just starting. My brothers 01 silverado would just turn over for a few seconds then fire up. It was his fuel pump and now it works perfectly. Don't know if that's what yours is doing.
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Old Dec 9, 2004 | 10:05 AM
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Originally Posted by maximumrebel1
Mine is always around 15-16. That is a weird problem. Do you have trouble with lights or is it just starting. My brothers 01 silverado would just turn over for a few seconds then fire up. It was his fuel pump and now it works perfectly. Don't know if that's what yours is doing.
I drove my truck on Sunday and noticed that everytime I would turn off the A/C that the volts would drop. That night the gauge was reading slightly below 14. I turn on my truck this morning and the gauge reads slightly over 14. On my way to work at a stop light the lights dimmed but the gauge dropped a lot and stayed there until I started to go again.
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Old Dec 9, 2004 | 11:03 AM
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I had the exact same problem with my 00' GMC. What ended up being wrong with mine was, the post on the battery itself had come loose and I was not getting all of the voltage. It caused my guage to do the exact same thing yours did and even caused my truck to run horribly at low rpm's. Check the battery post to make sure it didnt break inside the battery.
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Old Dec 9, 2004 | 11:06 AM
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dont know if this helps but my friend has a 97 mustang gt and the alternator was not bad but a little solenoid inside of it was it was a pretty rare occurance but he found out about it on one of his mustang boards i believe do not know if true or untrue just repeating what i heard hope it helps out some
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Old Dec 9, 2004 | 11:23 AM
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I believe that it is probably your battery giving you problems, make sure your serpentine belt is tight also.
Ryan
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Old Dec 9, 2004 | 12:18 PM
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Originally Posted by marc_w
With the truck off, you should see at least 12 volts.... but not really any more than 12.3 or so. If you don't that's a pretty good indication that the battery is weak. The sure-fire way to test that though, is to do the load-test that autozone probably did for you.
I just came from doing this and the gauge read just below the half mark in between 9 and 14. There are 7 marks between the 9 and 14 and the needle was sitting on the 3rd mark from the 9.
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