Have we got any car savvy people on the PC?

[Cap'nDrak]

Just taking a shot in the dark here, because I don't know a good mechanic in the area and I'd like to have a decent idea of what I'm getting into before I take my car to one of these backwoods clowns that think they can rape me.
Scenario:
About a month ago, my car battery died. I jumped it and it ran fine for a week. Then I jumped it again, and it ran fine for two weeks. Finally this last Friday, it died and when I jump it, as soon as I take the positive jumper line off, it dies.

Now, when it died the first time, I took the battery to Advanced Auto, and had them test the battery to make sure I didn't have any issues with it.
It checked out fine. (Meets standards or Above standards it what the paper they gave me stated)
The second time I jumped it, I borrowed a friends load tester, and it told me that my Alternator was charging within it's normal limits, about 14v.

Anyone have any clues? Do Alternators just flat out give up, or does their charging ability waver back and forth until it gives up the ghost? Should I recheck the battery to be certain?

Chris

[WRoss]

***Your Alternator just bit the dust!

[peam]

I drove with my stepfather to pick up an alternator for my car a few weeks ago so I'm pretty much an expert here.

[Jorddyn]

Could now be both your alternator and your battery. Take it back, get it tested again. Pick up an alternator while you're at it, as that was likely what caused the battery to die in the first place.

If your battery is more than a couple years old, repeated jumpings could have made it finally give up.

[BriarFox]

The easiest thing to do is to put a different battery in first and see if that works.

[WRoss]

One way to test the alternator is to remove the positive connection on the battery. If the car shuts off, alternator is not creating a charge. So...


Finally this last Friday, it died and when I jump it, as soon as I take the positive jumper line off, it dies.

[Delias]

You can also get a battery from most of the cars in a parking lot, free of charge.

[pabstblueribbon]

Buy a multi-meter. Learn how to use it.

[Cap'nDrak]

I did intend to run to Advanced Auto this weekend and have them retest my battery, just to be 100% and if it turns out it's still as good as the initial test then I'll pick up a new alternator while I'm there. Thanks for confirming my suspicions on this.
I'd rather handle this on my own than go to a mechanic in my local area. I've had bad experiences with almost all the mechanics around here in the past.
:thanx:

[Gan]

Alternator

[Amber]

Another vote for alternator, not that I'm an expert, but I like to tinker. I was taught that the easiest way to test if a charging problem is with the alternator or the battery is to unhook the battery once the car is running. If the car dies, it's the alternator, if it keeps running, it's the battery.

Good luck on finding a good mechanic. I found one about an hour from where I'm living now that's utterly awesome. As long as I'm in the area, I never plan on taking my car anywhere else. My AC stopped working when I was in Washington and the mechanic there charged me 170 for a diagnosis and said I needed both high and low pressure lines and it would cost over 700. Being Washington, I didn't really need AC so just lived without it, but after moving back to Texas, I decided I really needed to get it fixed. Called this particular garage (at the time I was living in the same town as his shop is in.), explained what the other shop had said and asked him to replace both the lines. He told me he wanted to do his own diagnosis first and I was thinking, "Oh flip, another 170 bucks to be told the same thing." but then he said the diagnosis would only be $30, so I figured what the heck and took it in. It was out of coolant, he refilled it, put some fluorescent dye in, and told me to bring it back when the AC went out. That was last September and it's still blowing cold. He could have charged me the $700 and not even replaced anything and I'd never have been any the wiser.

[WRoss]

I was taught that the easiest way to test if a charging problem is with the alternator or the battery is to unhook the battery


They forgot to tell you that in order for this to work, you need to stand in a pool of salt water, bare footed, and make sure you touch the negative with both hands.

[Sean of the Thread]

Alternator

Winner winner chicken dinner

[peam]

If it's the alternator, I'd check out junk yards first. Those bastards can get expensive, from what I understand.

New alternator with a one year warranty from both Advance and Autozone for my car was like $109.99.

Used alternator with a three month warranty from the local junkyard was $29.99.

Also if you have a wrench-turner in the family, the job may be a do-it-yourselfer. Me (who is totally fucking incompetent when it comes to anything more than turning on a vehicle and driving it) and my step-dad (who is reasonably mechanically inclined) changed mine out in about a half hour.

Then again, I drive an old car with not too much fancy shit under the hood.

[Smythe]

Battery, no water in cells. Shorted out da last time. Gonna have ta replace it.

- Smythe

[Cap'nDrak]

I'm not super amazing with cars, but after reading up on the maintenance manual I can manage to do this with some help from my dad. So that's the avenue I'm gunna go. And no joke about being expensive. The lowest price I was able to track down new is $144 from O'reilly Auto Parts. I'm gunna go new, because this car is my bread and butter, so I need to do this right. Junker parts could put a major dent in my work\travel plans if it does decide to go out. Even though the warranty would cover it, it would be lost time to yank it and put another one back in.

[Keller]

In college I had a similar problem with my jeep.

I was cheap so I tried to do it myself.

First I tried a new battery. Then a new alternator. Then, after I finally took it to a mechanic, it turned out to be a bad fuse.

Moral of the story: I also think it sounds like your alternator, but just check your fuses to save $200.

[Gan]

Look and see if your check engine light has come on. When you're at the auto parts store - ask the parts guy to hook up a diagnostic code reader to your car to see what error codes have been registered. This might help point to other issues that might have contributed to your alternator going out (other than old age of alternator.) Also consider what kind of load you're putting on your alternator. If you're running amps and other stereo (lights, etc.) equipment then you might consider upgrading to a higher output alternator to keep it from burning the new one out.

[AnticorRifling]

When you turn the car off, pop the hood and disconnect the battery. Go about your business (work, shopping, whatever). Get back to the car, plug the battery in, if it starts congrats it's holding a charge and you might have a grounding/short issue that's draining your shit when the car isn't on (and the battery isn't getting juice).

[Murkshev]

Okay, you are having to repeatedly just start your car? What kind of car is it, year, make and model please? I been in the auto business 10 years, I am ASE certififed and work at a dealership. Certain types of cars are prone to specific problems. This is only why I ask. Next what is the CCA rating of the battery and when it was tested without and with load what was the CCA rating? They should be using a Midtronics battery tester at Advance Auto. This information should be on the print out. Also the diode in an alternator can be weak, if you are getting 14 volts at idle, you might not get the same result if the headlights, a/c wipers and radio are on all at once, if you had you car at advance they have a portable tester to check the voltage output of the alternator under load at say 2,000 rpms. I can go on and on, there are some vechicles that had a votage regulator that is not apart of the alternator and are part of the PCM. So if you please? Year make and model and the results of the battery and alternator tests.

[Cap'nDrak]

It's a 2002 Pontiac Grand Prix 3.1l. I don't have the results of the original battery test. I won't get around to working on it until Saturday, when I tow the vehicle to a place I can work on it and remove the alternator for testing along with the battery.

[Murkshev]

Okay. With most GM models, if there is a battery light illuminated on the instrument cluster while you are driving it, that means the alternator is dead and you are driving under battery power. If you alternator is bad after getting it bench tested, if I remember this correctly, there are three spark plug wires that run past the alternator on their way to the back 3 spark plugs. The alternator is on top above the power steering pump right? I had a cavalier with the same motor but it was a 93. If that alt is dead, do this, at night with the car running, pop the hood and see if the spark plug wires are arching to the alternator casing. This could have been the cause for the alternator to kick the bucket.

[Murkshev]

Well after checking a used one here, I see that you won't have that old problem, since the wires are routed near the throttle body side.

[Cap'nDrak]

Correct. Earlier last month I noticed that the battery light would flash on then off while doing routine driving. Then as time progressed it would stay on longer and longer. I had assumed this was faulty, because the vehicle had a short in the after market car stereo's wiring harness *which I didn't know until recently*, but I did have a suspicion there was a short, because the dash cluster lights, headlights, and stereo would die then come back to life. The short I have corrected. I removed the car stereo completely, and all the after market wiring that went with it. (There were wires run for sub woofers and an amp.)

Even after removing all these things, when I jump the vehicle the battery icon lights up as soon as the engine rolls over, and continues until the vehicle dies after I remove the positive jumper line. The engine stops approx. 10-15 seconds after ignition.

[Murkshev]

In a few cars that I have worked on, depending on the size and wattage of an aftermarket system, its creates a constant load on the alternator. At peak the alternator for your car is rated at 110 amps. But most of the time it never puts out that much. Anyways, if you had a system in your car that ranged anywhere from 500 watts or more, you need to have had a capacitor added to relieve the strain on the alt. What you experienced is the death of the diode trio in your alternator. Constantly trying to run the car and charge an almost dead battery often, leads to a fast death. So once you do put a new alternator in and make sure you have a good fully charged battery, it will be smooth sailing again.

The booster pack is the only source of current. The alternator is not putting current out and the battery is not charged at all.

[Murkshev]

To prove the lack of battery power do this. Put the keys in the ignition and turn it so the accessories are on. All your lights should come on, have the door open, hear the door chime. Then turn the key forward and try to start the car. All the lights and the door chime should turn off, if that happens the battery is dead, it has some charge but under a load cannot put out the voltage needed to the starter motor or the rest of the electrical system. If at first nothing comes on then indeed the battery has no power at all.