Cascade Crew

Xophertony

ok, issue is with my 1986 Pontiac Firebird. 2.8L V6. manual transmission.

Symptoms:
Alternator is putting out 14+ volts at cruise. The car will not start off of the battery. if i put a DVOM on the battery i get 11 Volts, thats a little low, but it should be enough to start. i swap batteries with a spare. same story, this one has about 10 volts, but still won't start the car. the dash lights are dim and the charge guage on the dash reads <8V with the key on. If i DVOM the starter-to-battery wire i get 11 Volts. if i use a screw driver to bridge the starter to the solenoid (hey Paul, i spelled it right!) it will click, but not crank. I can roll start the car and it will run.

Backround:
Starter is new about 4 thousand miles ago.
Both batteries are circa 2008.
Alternator is a local parts store rebuild i got in LA, and is a piece of crap. at idle it only outputs 11-12V, but at anything over 1000RPM it charges at 14-15V. it has served me fine for almost two years now, and i am thinking that it is fine.
i have no PPD anymore
i have no power locks or windows
i have no clutch safety switch, it has been bypassed
i have no cruise control
all of my fusible links have been moved from the starter to the battery, and now have actual fuses. i checked these fuses.

Recent Changes:
the only "changes" to the electrical system in the past few days are as follows: i just put the radio back in, i hooked up the rear hatch pop, which is fed by ignition instead of hot, and i hooked up the 12 power outlet in my center console. as a method of eliminating any of this stuff from the mix, i have pulled the courtesy fuse which removes all that stuff from the mix. i also did all that on friday and the car has worked fine for a few days, which would eliminate that stuff.

i have the spare battery in the car now, on a trickle charger, just to be sure. but i am looking for any and all ideas of things to look for that could
A:be causing the car to not be able to start of a charged battery
B: if the trickle charger works; be killing the battery all of the sudden after only a few hours.

thanks crew, you guys are awesome. Smile

aaron_sK

chevymad · Posted: Tue Jun 08, 2010 9:01 pm Post subject:

Sounds like the batteries are dead or toast. They should have more voltage then that when sitting. Charge them and have them tested.

Twilightoptics · Posted: Wed Jun 09, 2010 5:46 am Post subject:

It's not voltage that runs the starter, it's amperage. You could have 12volts, and 10cca.

Xophertony · Posted: Wed Jun 09, 2010 7:49 am Post subject:

allrighty, well about to see of leaving the battery on charge all night has "fixed" the issue. if so the battery gets dropped off at baxters for deep cycle testing.

thanks for all the help guys Surprised

Xophertony · Posted: Wed Jun 09, 2010 8:07 am Post subject:

well, car fired right up on my spare battery. battery B. my original battery, battery A will be dropped off for testing.

so the way i see it i have a few options for what is wrong here:

1). Battery A just "up and died". and the car will be fine now that the other battery is in. this will be confirmed when the problem does not persist, AND when battery A fails testing at the parts store.

2). My shitty alternator is putting our proper voltage, but not enough AMPs. this will be confirmed when the problem does persist, and i am left with a dead battery again today.

3). something in the car is killing the battery. i have left the fuses out for my interior stuff, the radio hot wire is unplugged, and the two cigar lighters are unhooked. i will also unhook the ignition wire going to the hatch pop.

financially i hope that the battery has just failed. i have a spare so this would literally cost me nothing. but i am kind of leaning toward that alternator... that thing has me worried. but i have jumper cables and i know how to roll start a car. Cool

i'll keep you all apprised as things develop.

iansane · Posted: Wed Jun 09, 2010 1:48 pm Post subject:

My vote; battery.

chevymad · Posted: Wed Jun 09, 2010 4:28 pm Post subject:

If your spare battery has been sitting very long it may be toast as well. They say they only have a 6 month shelf life with no use. Optima's are 2 years. Some do better then others though.

Xophertony · Posted: Wed Jun 09, 2010 8:25 pm Post subject:

well, we shall see. the guys at baxtrers had it all day and forgot to try charging it. so they say they will leave it on overnight, i'll check in the morning. they checked my alternator and said it's fine, but they only tested volts not amps. i drove all day on battery b and it seemed fine. that said i am charging it tonight anyway. Wink

Xophertony · Posted: Thu Jun 10, 2010 10:10 pm Post subject:

so it charged all night.. .and would not take a charge. mystery solved. i hope.

83Z28BlackBetty · Posted: Fri Jun 11, 2010 7:13 am Post subject:

Sweet. glad that seems to be the problem... for now. That battery very well could have died because your shady alternator.

Like you said, you added a few fancy electronics (radio and hatch pop) that all require additional power. Your alternator could have barely been putting enough amps out to keep the car running and charge your battery, but as soon as you go around hatch popping and jamming out to Ace of Bace all day it is not able to keep up and hence does not fully charge your battery and kills it. Just a thought.

~JAKE

Xophertony · Posted: Sat Jun 12, 2010 11:13 pm Post subject:

Actually, I have had Rush - Moving pictures in since getting it back up and going, i can see why it is Rush's most commercially successful album.

Jake you make a good point. I have been driving a few more days now, and all seems fine, but i will monitor the situation. if this battery kicks the bucket i will rebuild that alternator. (i have decided when it goes i'm rebuilding it myself)