Idle voltage

Nope, MMM told me 11.5 was correct voltage...
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11.5volts won't charge a 12 volt battery, therefore any car left at idle would run down the battery.

I have read on many places that on 1980's cars and above taking the battery off of your car with it cranked can cause some serious issues.I never knew taking the battery off the car could you still run the car. I guess I didn't know this because all cars I have owned were or are newer than 1980s
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I am not suggesting to unhook anything, I am saying if charging voltage is not sufficient and the basics are checked the alternator is bad. Not rocket science. And why are you such a smartass in most of threads you post in?

Just go get an alternator and end it already.

 
It is weird, it has good times and bad times. On the way home tonight at idle down hills and whatnot the voltage was right at about 12.5. Still a bit low, but not in the 11s. With high beams on even.

Then some days it will just sit and idle at 11.8 or 11.9. It almost seems like 1/3 of the stator is only sometimes working. Which would cause the intermittent correct voltage.

Even if 1/3 of the stator completely goes, it will still work and not leave me stranded... does anyone have a really good reason I shouldn't just ignore it...?

 
It is weird, it has good times and bad times. On the way home tonight at idle down hills and whatnot the voltage was right at about 12.5. Still a bit low, but not in the 11s. With high beams on even. Then some days it will just sit and idle at 11.8 or 11.9. It almost seems like 1/3 of the stator is only sometimes working. Which would cause the intermittent correct voltage.

Even if 1/3 of the stator completely goes, it will still work and not leave me stranded... does anyone have a really good reason I shouldn't just ignore it...?
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Ignoring it could leave you stranded. Just get it tested if you are still on the fence. Most parts stores will check it for you. A new alternator isn't that expensive, worth the piece of mind. Good luck!

 
11.5volts won't charge a 12 volt battery, therefore any car left at idle would run down the battery.

I am not suggesting to unhook anything, I am saying if charging voltage is not sufficient and the basics are checked the alternator is bad. Not rocket science. And why are you such a smartass in most of threads you post in?

Just go get an alternator and end it already.
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His answer isn't a smartass answer, the alternator isn't the only thing that can cause charging issues. That is the reason I asked the question
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If the alternator was the only reason a charging problem would ever exit I would just go replace it.

There is a charge controller, cables than can come loose or corrode, etc, etc.

I really don't want to go buy a new alternator, and not have that be the problem. I'll do more investigation tomorrow.

 
His answer isn't a smartass answer, the alternator isn't the only thing that can cause charging issues. That is the reason I asked the question
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If the alternator was the only reason a charging problem would ever exit I would just go replace it.

There is a charge controller, cables than can come loose or corrode, etc, etc.

I really don't want to go buy a new alternator, and not have that be the problem. I'll do more investigation tomorrow.
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I hope you get it figured out.
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11.5volts won't charge a 12 volt battery, therefore any car left at idle would run down the battery.

I am not suggesting to unhook anything, I am saying if charging voltage is not sufficient and the basics are checked the alternator is bad. Not rocket science. And why are you such a smartass in most of threads you post in?

Just go get an alternator and end it already.
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What? I wasn't being a smart ass. I was just saying I have never heard of anyone taking there battery out of the car when it was running.

I have been saying it was the alternator the whole time.

 
It is weird, it has good times and bad times. On the way home tonight at idle down hills and whatnot the voltage was right at about 12.5. Still a bit low, but not in the 11s. With high beams on even. Then some days it will just sit and idle at 11.8 or 11.9. It almost seems like 1/3 of the stator is only sometimes working. Which would cause the intermittent correct voltage.

Even if 1/3 of the stator completely goes, it will still work and not leave me stranded... does anyone have a really good reason I shouldn't just ignore it...?
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It could lock up on you like mine did. Remember mine only gave me like a day notice then the next day she bit the dust and the battery was left with doing all the work. Needless to say I was stranded on the side of the road. Alternators are easy to replace on our cars so that is a good thing you should be able to do it yourself.

 
What? I wasn't being a smart ass. I was just saying I have never heard of anyone taking there battery out of the car when it was running. I have been saying it was the alternator the whole time.
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I'm still afraid to do it.. lol.

If the alternator is under load, charging the battery, and you suddenly release the load, won't it spike and fry the ECU and other electronics?

I have heard of it happening on boats, and causing a lot of electrical problems. On a boat it is more or less the same idea as a car, engine, alternator, charge controller, batteries, electronics, etc.

Plus, there are no capacitors in the charging system, so if it was running on just the alternator with the rectified AC it would be a very dirty DC power supply without the battery to stabilize it.

 
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I'm still afraid to do it.. lol.If the alternator is under load, charging the battery, and you suddenly release the load, won't it spike and fry the ECU and other electronics?

I have heard of it happening on boats, and causing a lot of electrical problems. On a boat it is more or less the same idea as a car, engine, alternator, charge controller, batteries, electronics, etc.

Plus, there are no capacitors in the charging system, so if it was running on just the alternator with the rectified AC it would be a very dirty DC power supply without the battery to stabilize it.
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The battery does not stabilize the voltage. The power is converted to dc long before it gets to the battery.

 
If you are afraid to change the alternator, you could ask for help.
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There are lots of people on here that would be willing to show you how to change it, so in the future you could do it yourself. You can right post after post about what it might be and be left stranded, or get someone there that knows what they are looking at to show you how to fix it. Once you went through it once you would have it for life. Just my .02.

 
I can change my alternator, we had it off when we pulled my engine. It isn't that hard.

 
and it would be in your best interest to find some one who rebuilds alt. cause usually one from any of the parts stores are a hit or miss thing where you could get one that last 1 month or you could get 1 that last for the rest of the life of the car.so if you want to waste time buy 1 from a parts store if you want to only do it once have a shop that rebuilds them rebuild it like morin's in brunswick or something closer to you if there is one

 
and it would be in your best interest to find some one who rebuilds alt. cause usually one from any of the parts stores are a hit or miss thing where you could get one that last 1 month or you could get 1 that last for the rest of the life of the car.so if you want to waste time buy 1 from a parts store if you want to only do it once have a shop that rebuilds them rebuild it like morin's in brunswick or something closer to you if there is one
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Is there anywhere I can find continuity tests for the alternator?

because we have a generator that wasn't working right and I found continuity tests I could preform and found out it was the stator. I replaced that, and it works again.

Is it that easy with the subaru alternator?

the annoying thing is that it works fine sometimes, like the past day and a half it has been working fine. So diagnosing could be hard.

 
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i don't know i have just always kept spair alt. around for subies so if one was showing signs of crapping out i would just replace it.you could alway go to the junkyard i work at in freeport and pick your self up a spair one for $10 it a self service yard so bring your tools mon-thurs 8-4fri-sat 8-3 there are a lot of legacys there just no impreza's so you should pay it a visit sometime

 
i don't know i have just always kept spair alt. around for subies so if one was showing signs of crapping out i would just replace it.you could alway go to the junkyard i work at in freeport and pick your self up a spair one for $10 it a self service yard so bring your tools mon-thurs 8-4fri-sat 8-3 there are a lot of legacys there just no impreza's so you should pay it a visit sometime
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Where in freeport is it? I may pay a visit.

What range of years will work with my car?

 
There is an older guy in Nobleboro, about 5 minutes from my place that can test alternators and rebuild them. He just rebuilt mine a few weeks ago He is cheep and very thorough. Also I will add my 2 cents......You can unhook the battery and all will be fine. It will continue running without causing any damage. I have driven cars several miles without a battery in it at all. It was fine. Good luck!!

 
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