Car trouble, please help!

BatmanNate

Lifer
Jul 12, 2000
12,444
2
81
Hi,

My car has a problem. The battery level will get lower and lower until it won't start anymore, but once it's running it keeps going, nothing dies. I've tried 2 different batteries, 1 of them was new, and the same thing happens. The alternator is also brand new, but it's a piece of turd from Schucks. I would think that if the alternator was the problem, then I wouldn't be able to drive alright once it's started, but I don't know that much about cars. Any ideas on what could be wrong? Cabling is all clean and secure, as is the belt on the alternator.

EDIT:

It doesn't just lose power when the vehicle is off, also when it is running. It won't charge it back up while it's running, either.
 

Lucky

Lifer
Nov 26, 2000
13,126
1
0
sounds like you have an electrical gremlin thats sucking juice when the car is off.
 

TonyG

Platinum Member
Feb 12, 2000
2,021
2
81
When my alternator was going out, the car would run just fine after it was started because the alternator was able to produce just enough charge to keep it running. Though, when you are starting the car it takes a lot more amps to turn the engine over, effectively running the battery down. The other thing to do is to check and make sure you don't have a light or other electrical device being left turned on in the car. If you have a Oreilly's Auto Parts Store near you, take the alternator to them and they will test it for free. Also, don't bother to buy one of there cheap 1 or 2 year remanufactured alternators, get the remanufactured one with a lifetime warrenty, it is not much more and well worth the extra cost, that is off coarse if you need a replacement alternator. I went through 4 of the cheap remanufactured ones before upgrading to the one with a lifetime warrenty.
 

BatmanNate

Lifer
Jul 12, 2000
12,444
2
81
Hmm, thanks for the info. The thing that gets me is that this alternator is like 2 days old, freakin Schucks. It does have a lifetime warranty, and this is the 4th one from that warranty. Can anyone reccomend a good brand and about what it costs? It's for an '82 Toyota.
 

BatmanNate

Lifer
Jul 12, 2000
12,444
2
81
The other thing is, when the car is running, it doesn't charge the battery to it's previous level. It just keeps going down, but it won't die. WTF? It's like it can power the car fine, but not recharge the battery.
 

TonyG

Platinum Member
Feb 12, 2000
2,021
2
81
Really sounding like the alternator to me. The ones I went through all had a year or so warrenty on them, but I changed them out 4 times within about a month and a half, when the 4 one went out, Oreilly's allowed me to trade it in for one of the better ones, and just pay the difference between the two. After the second time I brought one in, they guy did not even bother to check the alternator, just pulled another off the shelf for me. The one I have now is an AC Declo, if I remember correctly, and it is doing great.
 

GrumpyMan

Diamond Member
May 14, 2001
5,780
266
136
Well that means that you have a short somewhere that is draining your battery. It can be very difficult to find. I had a dome light that had the wires rubbed raw touching the roof of my van with all the vibration over the years. My cigarette lighter also shorted out and killed a couple of batteries before I figured it out. Check out your fuse boxes both inside and under the hood to start the trouble shooting process. If any fuses are burned out, then at least you know what circuit to check out.
 

KennyH

Diamond Member
Sep 16, 2000
5,904
0
0
I believe it is the alternator, have you replaced the voltage regulator? EDIT: What GrumpyMan said could also be a problem as well. :(
 

BatmanNate

Lifer
Jul 12, 2000
12,444
2
81
Thanks for the responses! I thought about it being a short, but if it were just a short draining it, you would think the alternator would recharge the battery while the car was running. I haven't messed at all with the voltage regulator. (I don't even know where it is, just got this car from my buddy a few days ago lol) Any idea how much a decent alternator costs?
 

Tominator

Diamond Member
Oct 9, 1999
9,559
1
0
I went through 4 of the cheap remanufactured ones before upgrading to the one with a lifetime warrenty.

Sorry to burst you bubble, but paying extra for a 'Lifetime Warranty' gets you nothing but insurance. They are exactly the same unti! You are just buying an extended warranty.

You may buy a brand new alternator or a rebuilt unit. They are remanfactured to like new and paying for a new one is money wasted imho.

Autozone, for instance, warranties all their rebuilt alternators for 'life,' while NAPA tries to get extra cash for a 'lifetime warranty.' There is no difference in the two units sold by NAPA!

Rebuilders bid on contracts to major retailers and although there can be bad runs of anything, they are all equivalent. Now you will here this disputed by many mechanics and I will leave it at that as I've been very involved in this process in the past and will not argue this...for a change...;)
 

Pacfanweb

Lifer
Jan 2, 2000
13,158
59
91
<<Bubble bursted or not, I've had good luck so far with rebuilt alternators from Napa. >>

But what Tom said is there's no difference in the standard reman. alternator from Napa and their "lifetime warranty" alternator. I don't doubt it. They just charge extra for the same alternator and warranty it for life instead of 90 days or a year or whatever the regular one is waranteed for.


I'd recommend you start with having the charging system checked.
 

BatmanNate

Lifer
Jul 12, 2000
12,444
2
81
What exactly constitutes the "charging system" ? I drove the car to work today, and when I got there, the thing was ALMOST gone, I mean lights were dim, stereo was off, engine still running fine. So I kill it, then turn the key to see what happens, it turns over like a half a time, so I figure I'll get a jump in the morning. Well, I go out to my car in the morning, fire it up, and it starts right up, with the battery guage almost full again. Beats me, let me tell ya. It drove home fine though, I'm hoping for a relapse of this self charging behavior until I get a day off to mess with it. :D

 

Bignate603

Lifer
Sep 5, 2000
13,897
1
0
I would think you have a small short, like somebody else said (not a mechanic so this is just me taking an educted guess). One of the little plastic things that holds all the wires in a bundle in the engine compartment once let one of the main wires right from the battery pop loose in my car and let it rub against a belt. It wore a hole through the rubber, then the wire shifted back so it looked like nothing happened. Every now and then it would touch the frame and make me loose spark while the car was running (once at like 40 mph) and it would just die on me. It took forever to track that down. The worn insulation is currently replaced by electrical tape and I ziptied the the wire back in place.
 

Cyberian

Diamond Member
Jun 17, 2000
9,999
1
0
If any fuses are burned out, then at least you know what circuit to check out.
If the fuse is blown, there shouldn't be any current flowing in that circuit, should there?
You've gotten some good advice so far. This does sound like an odd problem.

One more vote here for checking the voltage regulator.
 

Tominator

Diamond Member
Oct 9, 1999
9,559
1
0
I would think that if the alternator was the problem, then I wouldn't be able to drive alright once it's started, but I don't know that much about cars.

The battery, although low on charge, may be able to provide enough power to run the car....for a while. The fact that you've already changed batteries points to the alternator/chargeing system as the culprit

Most alternators have the voltage regulator within the alternator and should be replaced as a unit.

On some models the injectors need a certain voltage to operate and the car not running at all might be the first hint of chargeing system problems. This would mimic a bad fuel pump.
 

BatmanNate

Lifer
Jul 12, 2000
12,444
2
81
The battery terminals are spotless and secure, checked that. If the voltage reg is part of the alternator itself, how do I check that? I am going to go take a look at the fuses and then report back in just a second. Also, the car has a carb, no EFI, so that shouldn't be a prob. Thanks again for all the help and suggestions!