bad alternator???

product1620 · Post by **product1620** » Wed Jan 03, 2007 10:49 pm

Once upon a time, I went outside with the intention of getting in my pretty black fiero and driving it to the local garage to have them remove some locking lugnuts that I didn't have the key for, but when I went to start the car NOTHING HAPPENED! (dun dun dun!!!!), so I jumped the car off, and drove it around for a few minutes to build the charge back up, while I was driving around, I noticed that my cd player kept cutting on and off, but it seemed to happen mostly when I applied the brakes, frustrated by now, I ignored it, and headed to the shop, I got there and was told to come back the next day, but when I attempted to leave I found that my car was dead again! (DUN DUN DUN!!!) angry by now I went inside and asked for a jump, I had some trouble, but after wiggling the cables it jumped off, I then returned the portable jumper got in the car (by now it was dark out) I went to flip my lights on, but as soon as I did, the car died, as if I just hit a "kill switch". The mechanic there said he thought it was the battery, and to leave the car there and come back the next day, so I did just that. The next day I got in the car started it up, and drove home, car ran great.

I went on vacation for 9 days, when I came back I decided to head back to the shop to get the locking lug nuts removed, because they neglected to do that, the last time the car was there. The car started right up, and drove to the shop just fine, I left the shop went to the parts store, got some parts, and got back in the car, started up fine, but when I started to drive I noticed that the radio started cutting in and out like it did before, I again ignored this and went home, when I got home I shut the car off, went inside for a bit, then when I came back out to move the car.
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.IT WAS DEAD!!!!! (DUN DUN DUN!!!!) so the only thing I can think of is that my alternator is not chargeing my battery, but if it is a bad alternator then would the car be able to stay running after being jumped? Maybe its providing just enough juice to keep it running but not enough for the radio or to charge the battery???

Series8217 · Post by **Series8217** » Wed Jan 03, 2007 11:02 pm

Just so you know, trying to charge a dead battery off the alternator generally kills the alternator.

product1620 · Post by **product1620** » Wed Jan 03, 2007 11:04 pm

Why, isn't the alternator constantly charging the battery, anyway?

Series8217 · Post by **Series8217** » Wed Jan 03, 2007 11:07 pm

product1620 wrote:Why, isn't the alternator constantly charging the battery, anyway?

Well for one thing, when the battery is dead it draws a lot more current when charging..

Xanth · Post by **Xanth** » Wed Jan 03, 2007 11:11 pm

Series8217 wrote:
product1620 wrote:Why, isn't the alternator constantly charging the battery, anyway?
Well for one thing, when the battery is dead it draws a lot more current when charging..

New alternators even come with a warning not to install it in a car with a dead battery. You should replace the bat or charge it before using it again in the car.

Have you already checked the voltage while the car is running? You may still be right about the alternator being dead.

product1620 · Post by **product1620** » Wed Jan 03, 2007 11:11 pm

Well for one thing, when the battery is dead it draws a lot more current when charging..

Thank you, i'll add that to the list of shit never to do again. Judgeing by the cars symtoms would you say that I am correct in guessing its a bad alternator???

Xanth · Post by **Xanth** » Wed Jan 03, 2007 11:13 pm

Do your headlights flicker as the engine rpm changes, like at an idle? May also just be your battery isn't holding a charge and your car is pretty much running off the alternator.

Did the mechanic replace your battery already when he said he thought it was bad? Or did he just charge it?

product1620 · Post by **product1620** » Wed Jan 03, 2007 11:14 pm

Have you already checked the voltage while the car is running?

No, im kind of burnt out with this car right now, but as soon as I feel like I can work on it with out beating the fuck out of it with a mallet, I will do so.

product1620 · Post by **product1620** » Wed Jan 03, 2007 11:16 pm

Xanth wrote:Do your headlights flicker as the engine rpm changes, like at an idle? May also just be your battery isn't holding a charge and your car is pretty much running off the alternator.

Thats was my first thought, which is why I had the battery replaced with a new one, now im back in the same boat as before.

Xanth · Post by **Xanth** » Wed Jan 03, 2007 11:17 pm

Another possibility is overcharging the battery, don't know if this is common with Fieros, but happened with several of my Hondas. The voltage regulator would fail and charge the bat at 19 volts or so until it fried and wouldn't start the car anymore and would die very soon after fully charging. The car ran excellent once it was got running however. I replaced at least two batteries before I figured out that problem.

Really though, just stick a voltmeter to it. You may just have a slow drain somewhere while the car is off, or if it is over/undercharging you will know right away.

product1620 · Post by **product1620** » Wed Jan 03, 2007 11:49 pm

I doubt that, because the car had been sitting for 9 days, and it started right up, but after driving it for 10 minutes, then letting it sit for 15 minutes the car was dead.

cactus bastard · Post by **cactus bastard** » Fri Jan 05, 2007 11:53 pm

I had very similar symptoms when one of my battery cables was in bad shape.
Sometimes it would work great, sometimes it would need a boost, sometimes it would work OK but only as long as my lights weren't on or anything.
So it could be a connection somewhere too.

p8ntman442 · Post by **p8ntman442** » Sat Jan 06, 2007 10:54 am

How about some real advice.

1. Check battery voltage with car off.
2. Check alternator output when running (can be checked at the battery)
3. Know that without a good battery to supply a field to the alternator, it will not produce voltage to charge the dead battery.

Xanth · Post by **Xanth** » Sun Jan 07, 2007 7:58 pm

Yes, way to restate all that has already been said :thumbleft:

Kohburn · Post by **Kohburn** » Mon Jan 08, 2007 8:17 am

cactus bastard wrote:I had very similar symptoms when one of my battery cables was in bad shape.
Sometimes it would work great, sometimes it would need a boost, sometimes it would work OK but only as long as my lights weren't on or anything.
So it could be a connection somewhere too.

sounds like you were running off the battery -- and not the alternator.. after letting a battery sit for 9 days it will usually recover some charge but get drained again quickly.

i think your alternator is dead or the cable to the bat is not allow it to charge the battery.

cactus bastard · Post by **cactus bastard** » Mon Jan 08, 2007 7:22 pm

Kohburn wrote:
cactus bastard wrote:I had very similar symptoms when one of my battery cables was in bad shape.
Sometimes it would work great, sometimes it would need a boost, sometimes it would work OK but only as long as my lights weren't on or anything.
So it could be a connection somewhere too.
sounds like you were running off the battery -- and not the alternator.. after letting a battery sit for 9 days it will usually recover some charge but get drained again quickly.

i think your alternator is dead or the cable to the bat is not allow it to charge the battery.

Yeah, that's what I was trying to say; sorry if it wasn't clear. I had a bad cable.

blackice1620 · Post by **blackice1620** » Thu Jan 11, 2007 12:48 am

Product your car is garbage, DIAF!!!