alex722607

iTrader: (3)

Hi Everyone,
So I have yet another problem with my car.

Today I drove my car to school, everything normal for a 30 mile drive.
After my class was finished, I get in the car and try to start it..... cranks for 5 seconds, then the starter begins to click like the battery is under 12 volts ... way under.

Guage reads (digital dash) 11 maybe 10. So my dad comes with jumper cables and after some wiggling of the cables and a few tries, it miraculously turns over.

I'm on the highway and the guage is reading 10, 11, but the car isn't shutting off. I get home and check the battery voltage with a multimeter and it is reading 11.4, car is still running. Keep in mind it made it 30 miles at the voltage, sometimes fluctuating between 13 and 10.

My alternator is charging, it had to be to make it 30 miles. Could this be the battery? When I got home I shut it down and cranked it, wouldn't even turn over (not even close).

I am leaving it on an overnight charge and will load test it in the morning. Anyone here experience this or anything like it before?


PS: and yes I checked if the cables were loose at the battery, I even changed the bolts on the cables.

alex722607

iTrader: (3)

So this morning I load tested the firebirds battery ( after a night of charging and after first starting the car- to see if it starts). The tester told me that the battery was on the verge of being in the red (bad). I guess I am going to get a new one. In addition, when I got home, my factory radiator finally gave out... Leaking at the seams that is. Wasn't a good day.

RedLeader289

iTrader: (2)

Make sure all your cables are making good connections. For a daily driver the general life expectancy of a battery is about 5 years, so if yours was around that age then it would make sense.

alex722607

iTrader: (3)

The battery is a little over 2 years old. I replaced the positive and negative cables bolts as well. This morning I started it, no jump starting was necessary and charger was off, ... Went for a drive and it was doing the same exact thing meaning 10 -13volts. I come home shut it down and it starts back up no problem. My dad thought it was a loose cable, but they were pretty tight. The load test on the battery (w/ key off) told me the battery is failing.

My conclusion is the battery must be bad. However, is it possible for the alternator to only charge at a certain rpm ...say 1000+. Therefore at idle it wouldn't charge or would intermittently.... I am stumped.

And yes it is a daily driver, for the winter the battery is on a float charger.

RedLeader289

iTrader: (2)

Mmk, if you're sure the cables are good then replace the battery.

No, the alternator will charge at idle (otherwise batteries would go down a lot more often).

RedLeader289

iTrader: (2)

Sometimes you just have a dud battery, it's happened to me before.

alex722607

iTrader: (3)

I wouldn't be surprised about the battery. However what is making me weary about the alternator is that it was in this car before...it worked fine but was swapped for another. Last year that other went bad and my dad put this one in. It has been a trooper since, but it has an unknown number of miles on it.


Sorry about making this complicated.

RedLeader289

iTrader: (2)

No worries! I can understand the concern. Autozone/Advanced Auto has testers for alternators that they'll do for you for free if you're worried about it, that would remove all doubt.

I've only had one alternator go bad on me and it just flat out stopped charging, worked great the day before, and then boom. dead.

alex722607

iTrader: (3)

So, today after my battle with my radiator, I decided to tackle the battery and alternator.

I bought my battery 2 years ago in Walmart with a three year warranty
(yes.... I know .... Walmart).

anyway after fighting with them and them finally giving me a new battery, I installed it. Car ran fine, bu the guage reads 11-12 volts. The same on the multimeter when applied to the battery. When I hit the cruise controller under the hood to rev up the engine, the readings indicate 11.98-12 volts.

I distinclty remeber my readings used to be in the 12.6-13 volts range, especially with the engine at 1200-1300 RPM's.

Looks like I might be getting a new alternator.

alex722607

iTrader: (3)

So something did not seem right to me about my charging and about the battery. So I started looking at various threads and bingo I found my answer. As soon as I cranked out my good ole FSM and double checked something the answer was right there in front of me.

Fusible Link J.

There is an assortment of fusible links by the starter, well this particular one supplies battery power to the big red fat wire on the alternator connector, also known as pin S. It is supposed to carry battery voltage at all times. Well my big fat red wire, did not carry battery voltage.

I jumped Pin S with a hot at all times source (the battery) and protected it with a 30 amp fuse (just in case, it never hurts). I then started the car and watched the volt guage jump past 13 for the first time since Wednesday.

If anyone ever has problems with their alternator not charging, ...... check the terminals on the alternator.

Gotta love GM ingenuity.

I am fixing this by ditching the fusible link and putting in an inline fuse

alex722607

iTrader: (3)

Update: well it wasn't the fusible link, instead the connector for the wire on the starter just broke, causing intermittent connection. So I replaced it and reassembled it. Plug the battery back in, key in, turn to crank, bam no power- everything shuts off- dead. So I get back under there and pull off the connectors and shine a light...... Black. Carbon build up caused a bad connection. So I got the old wire brush out and cleaned them. I put it all back together, crank, jumps to13.5-14 volts. As soon as it charged and I drove it a bit to steady the idle, I started playing with my windows and headlights. Well guess what- everything is better, I don't think I have ever seen those windows move that fast. Anyone have problems with windows- check the connections at the starter...,, you'll be surprised. (Headlights are brighter too)