Battery issue, or more?

So a little background before going into the issue. I have an '06 LGT 5EAT with a little over 75k miles. I bought it in March of '13, and it had 42k miles on it. From those numbers, I'm guessing the battery is still the original, as it is a Subaru OEM battery.

I was off for about a week after Christmas, drove my car very little. One night, the first bitterly cold one (around 25*F) I was leaving a friend's house late, and I got to the first stop light about a mile from his house. As I pulled up to a stop, the engine just quit. I believe all the lights flickered but stayed on, headlights and all. I turned the key, the engine turned a few times but didn't start. I then shut the heater, seat warmer, and radio all off, waited a few seconds, then tried again. It started up on the second turn of the engine. Ran fine the drive home, including a few more stops.

Now I'm trying to cover my bases. To me, it looks like a simple battery issue. HOWEVER, I took it to the local automotive shop who tested the battery and it read at a tick above 81% charged. It threw me, but I decided to put it back in and give it another chance. I cleaned the terminals and the connectors, and laid it back in it's home. For a couple days after it ran normally. The temperature did rise to about 40*F average during the sunny hours for the following few days.

Then, this morning, again dipping to a very brisk 15*F, started the car, engine not doing anything different, took about 3 engine turns to start. I've read that's normal as it cycles oil into the engine. Anyways, let it rumble for a minute or two, then went on my way. I got about two miles down the road, to a stop light, and again as I came to a stop the engine shut off, everything else still on. Shut off the heater, seat warmer, mirror heaters, and turned the key, engine popped back on. Again, no further problems.

Sorry for lengthy narrative, but I'm just making sure I hit the details. Does this sound like a simple battery issue, or does it smell of deeper problems –*alternator, wiring, etc. If anyone can weigh in I'd be very thankful. I'm planning on swapping out the battery anyway, but if that doesn't solve it than I'll know some sort of direction to head. Thanks in advance to all your wonderful wisdom that always seems to pop up!

First let me say, I may not have many posts here but go over to NASIOC and have a gander.

Get the alternator tested and replace it. Check alt belt tension and make sure the belt is present

A car uses the battery to start and run accessories only. During operation the alternator is what keeps the car going.

Remember this point, short trips and idling (warming the car with heater) all the time can lead to premature battery failure. For instance you live only a few miles from work. If you constantly use your accessories, headlight ect at night for those short distances your battery hasn't had a chance to get completely charged. You need to drive your car a longer distance every now and then to get the deep cycle charge.

Little test

Jump start the car or charge battery

Open door to turn on dome light

Turn on headlights

Remove the jumper cables

Watch the dome and headlights

If alt is bad headlights and dome lights will dim and remain dim

If alt good, dome and headlights may go dim for a second and then brighten back up.

If that indicates good alt then turn on heater full blast and continue to watch the lights

Get the alt tested before new battery or if it's bad it will only kill the new battery, it can kill the cells as well.

My car still has the original battery 2005, it's just now starting to go, i use a different kind of test but it's highly scrutinized with newer vehicles so won't get into it here.

I'll second having the alternator tested, as a dead/dying battery shouldn't cause the car to stall out. Most auto parts stores should be able to do a full charging system check, usually for free. If you have a voltmeter, you could also check the alternator output yourself to see if it's delivering the 14.x volts it supposed to.

These cars seem to be pretty picky about correct voltage though. When my battery suddenly died, the dash illumination began to act strange, and the ABS light on the dash came on. Car still ran fine though.

Update:

Started the car up fine for the drive back to autozone to have the alternator checked last night, hit minimal stop lights on the way so no chance of it dieing at low-RPMs (which seemed to be the one common factor). Once I got there they again checked the battery first, this time it read as "bad". No idea what they're criteria are, which is confusing because it read "over 81%" the last checkup done not a week before.

Anyways, replaced the battery, everything is fine so far. I did a little more research and apparently with the way modern batteries are designed, if one or more cells fail it can cause a plethora of different issues depending on how a particular car is made. Some people even had the engine stall out on the highway! It has to do with the running amps (I believe this is the correct term, however I could have it wrong) needed to run the various systems, and as a "protection" from not enough power being available, things will just shut off. In older cars, you could notice lights dimming on the dash or headlights flickering or what-have-you as it lost those running amps. It's kind of a catch-22 to me, I'd rather know when a battery is dieing rather than it going out on me at 1am on a pleasantly 10*F night...

Either way, we'll see if it holds up to the true test- time! Again, you all are great, thanks for your time!

Update:

 

Started the car up fine for the drive back to autozone to have the alternator checked last night, hit minimal stop lights on the way so no chance of it dieing at low-RPMs (which seemed to be the one common factor). Once I got there they again checked the battery first, this time it read as "bad". No idea what they're criteria are, which is confusing because it read "over 81%" the last checkup done not a week before.

 

Anyways, replaced the battery, everything is fine so far. I did a little more research and apparently with the way modern batteries are designed, if one or more cells fail it can cause a plethora of different issues depending on how a particular car is made. Some people even had the engine stall out on the highway! It has to do with the running amps (I believe this is the correct term, however I could have it wrong) needed to run the various systems, and as a "protection" from not enough power being available, things will just shut off. In older cars, you could notice lights dimming on the dash or headlights flickering or what-have-you as it lost those running amps. It's kind of a catch-22 to me, I'd rather know when a battery is dieing rather than it going out on me at 1am on a pleasantly 10*F night...

 

Either way, we'll see if it holds up to the true test- time! Again, you all are great, thanks for your time!

Should have had AZ check the alternator while there.

A battery will NEVER cause a modern day car to stall. Once the car is running the alternator takes over. As I stated above replacing the battery without testing the alternator is nothing more than "putting lipstick on a pig" as soon as the battery charge is depleted the same thing will happen if the alternator is bad.

That's the reason the battery showed good 88% after a charge is actually not good! should be holding 100%. 13.4-7 volts sometimes 14-14.2.

Yesterday when you drove it to parts store the charge had been pulled because the alternator is failing.

A failing battery can kill an alternator just as a failing alternator will kill a battery. Once started your car should run fine even if you take the battery out or disconnect it. (Not recommended with the modern vehicles) but I have done it with my old WRX when in a pinch.

Best of luck

Check your engine to chassis grounds.

If engine yo chassis ground was the problem the car would not jump over or start if battery is changed!

Good info, seems to contradict the sites I found on other automotive sites though. Either way I need to return my old battery (which I found is the original one, making it ~8 y/o), and I'll have them test the ALT when I'm there. No need to let the fancy lipsticked-pig die on me! Thanks Dibblejr!

No problem but let me clarify one point above.

Alone a dead battery will not cause a car to stall, however if you combine all of the accessories ie, lights, stereo and heater which it sounds like you probably needed can cause the car to stall IF you stop. Remember fuel pump, ecu and other electronic components under the hood utilize electrical power.

However if you were driving on an interstate the alternator will run the car even if you removed the battery altogether. At highway speeds a good alternator will sufficiently power every component in your car.

I wasn't poking fun at you, not my style, at my age I've outgrown that. Just trying to pass on my 35 years of automotive information.

Best of luck

JR

If engine yo chassis ground was the problem the car would not jump over or start if battery is changed!

wat?

No problem but let me clarify one point above.

 

Alone a dead battery will not cause a car to stall, however if you combine all of the accessories ie, lights, stereo and heater which it sounds like you probably needed can cause the car to stall IF you stop. Remember fuel pump, ecu and other electronic components under the hood utilize electrical power.

 

However if you were driving on an interstate the alternator will run the car even if you removed the battery altogether. At highway speeds a good alternator will sufficiently power every component in your car.

 

I wasn't poking fun at you, not my style, at my age I've outgrown that. Just trying to pass on my 35 years of automotive information.

There are a couple of situations where the battery could be the source of the problem.

The first being a completely discharged battery. In such a state it could be drawing sufficient power from the alternator to starve other electrical components. Not the most common issue but one to be aware of if the battery is completely discharged or old.

The second being a battery with internal damage which could be shorting to ground. Similar to the above power would be siphoned off due to the short.

In general I agree with your statements.

8 years is a long life for a battery. I replace mine at 5 years or before the coming winter just in case...

yours is an 2006, I would replace the chassis from the heads to chassis. Common issue with these cars. There's a thread here about it.

Also being a 06, you have that old black o-rings between the intake and TGV's, in cold weather they are know to make the car stall. They should be replaced with the new larger orange ones.

wat?

If the "chassis ground" was the problem, the car would not jump start! PERIOD

OP stated he was able to jump the car!

8 years is a long life for a battery. I replace mine at 5 years or before the coming winter just in case...

 

yours is an 2006, I would replace the chassis from the heads to chassis. Common issue with these cars. There's a thread here about it.

 

Also being a 06, you have that old black o-rings between the intake and TGV's, in cold weather they are know to make the car stall. They should be replaced with the new larger orange ones.

In the OP's case it's not the O-rings between the TGV's, it's electrical.

Personally I have never seen the TGV o ring problem on any of my Subarus old or new.

I think he will find the alt being the culprit here.

If the "chassis ground" was the problem, the car would not jump start! PERIOD

 

OP stated he was able to jump the car!

So! Are you saying that an intermittent ground issue would disallow a jump start in every single circumstance?!?!?! That doesn't quite sound right! I told him to check them to validate if there were an issue or not! I stand by that as a valid troubleshooting step irrespective of your curious exclamatory emphasis!!!!!

I love watching the answers come through from this community, you all seem to be able to drill down almost every scenario.

I had the alt checked, and it's fine. Looks like it was just the battery! Once again, thank you for all your time and info!

First let me say, I may not have many posts here but go over to NASIOC and have a gander.

 

Get the alternator tested and replace it. Check alt belt tension and make sure the belt is present

 

A car uses the battery to start and run accessories only. During operation the alternator is what keeps the car going.

 

Remember this point, short trips and idling (warming the car with heater) all the time can lead to premature battery failure. For instance you live only a few miles from work. If you constantly use your accessories, headlight ect at night for those short distances your battery hasn't had a chance to get completely charged. You need to drive your car a longer distance every now and then to get the deep cycle charge.

 

Little test

 

Jump start the car or charge battery

Open door to turn on dome light

Turn on headlights

Remove the jumper cables

Watch the dome and headlights

If alt is bad headlights and dome lights will dim and remain dim

If alt good, dome and headlights may go dim for a second and then brighten back up.

 

If that indicates good alt then turn on heater full blast and continue to watch the lights

 

Get the alt tested before new battery or if it's bad it will only kill the new battery, it can kill the cells as well.

 

My car still has the original battery 2005, it's just now starting to go, i use a different kind of test but it's highly scrutinized with newer vehicles so won't get into it here.

All of this entire post is 100% incorrect information. The car runs ON THE BATTERY. The alternator is nothing but a battery maintainer and keeps the reservoir (battery) full. Without a good battery, nothing in the car will work correctly and HERE'S a test. Remove the battery and make the car run. You'll have to hook up jumper cables to someone else's car just to start it, and generally you'll wreck their alternator too. Try to drive it down the road and see what happens-it will not go very far and you'll see the alternator burn up from the smoke and sound coming from the engine bay.

Remove the alternator and put in just the battery and start the car and drive it for a couple of hours until the battery finally goes down too far to continue to power the electrical system in the car. Replace it with another fresh battery, and you're on your way again until that one goes down.

After you replace the alternator again because you just destroyed the first one by running it at 100% capacity and destroying the diode trio inside, then put a fully charged battery (12.6V) back in, and find out that it's the battery that keeps everything alive.

This continues to come up again and again. The alternator does nothing except charge the battery while the car is running. An average usage of amperage for most vehicles in normal weather is anywhere from 60-80 amps of continuous draw. The alternator generally runs from 80-105 amps on most normal vehicles (not including ambulances or commercial vehicles or highly modified vehicles with huge stereos, etc.) and it runs at about 60% capacity when it goes down the road at higher rpm. When you turn on more accessories, the ECM senses this and tells the alternator to turn up the juice and then moves to replace it, but there is no ass behind the amperage until it reaches the battery and relies on it's capacity and depth.

I taught this very subject-electrical and electronic system diagnosis and circuit voltage drop testing for several years at the installer level and also at W/D seminars, and believe me, there is no bigger myth in automotive than the one about the alternator being what runs the car. Again, it does nothing except maintain the battery at it's capacity.

No problem but let me clarify one point above.

 

Alone a dead battery will not cause a car to stall, however if you combine all of the accessories ie, lights, stereo and heater which it sounds like you probably needed can cause the car to stall IF you stop. Remember fuel pump, ecu and other electronic components under the hood utilize electrical power.

 

However if you were driving on an interstate the alternator will run the car even if you removed the battery altogether. At highway speeds a good alternator will sufficiently power every component in your car.

 

I wasn't poking fun at you, not my style, at my age I've outgrown that. Just trying to pass on my 35 years of automotive information.

 

Best of luck

 

JR

Again, 100% incorrect information. A dead battery will absolutely cause a car to stall and it will destroy the alternator in the process. You cannot simply jump a dead battery and as soon as the car starts, just jerk the cables and go on your merry way. It will work, but you've drastically shortened the lifespan of the alternator in that it's trying to fill a completely empty reservoir with a trickle and the outpour from the battery is much larger. In a short period of time, it will destroy the diode trio from heat, and then you have BOTH a dead battery AND a blown alternator.

The alternator will NOT sufficiently power every thing in the car. It will basically burn up very quickly and then cause several other things to happen in that the ECM can be bricked by the spike in AC current from the alternator when the diodes fail, and also can destroy the TCM and BCM as well.

Again, a myth that the alternator will run a vehicle. It will NOT do this.

I don't want to jack the thread, but this information could be useful to the OP as well down the road.

What is the best way to test your alternator? Are the tools places like autozone use reliable? I ask because my car has 162k and I'm still running my original alternator, and I'm not sure how long they last on these cars. The only car I've had to replace an alternator on was a civic, which lasted until 130k, with one 10" sub which may have shortened the life of the alternator.

I don't want to jack the thread, but this information could be useful to the OP as well down the road.

 

What is the best way to test your alternator? Are the tools places like autozone use reliable? I ask because my car has 162k and I'm still running my original alternator, and I'm not sure how long they last on these cars. The only car I've had to replace an alternator on was a civic, which lasted until 130k, with one 10" sub which may have shortened the life of the alternator.

The best way for anyone to test their alternator is to remove it and take somewhere that has an alternator/starter testing machine. There are ways to test them on the vehicle, but there is always the possibility of causing some other failure in your own vehicle because of shorting something out or hurting yourself in the process. It's an expensive proposition to make a mistake that only causes a single spark but can cost $1000 for an ECM+.

If your car is running fine but you suspect the alternator to be not charging as it should be, then simply remove it and take it somewhere you trust (usually anything with "Auto Electric" in the name is good) and have them test it on premise. The electronically controlled alternators require certain parameters that call them pass or fail, and the test equipment has the correct plugs and are able to trigger the internal electronics that test the diodes correctly and safely without damaging them or anything else.

Take the alternator off and have someone reliable test it for you. Fortunately, it's easy and quick to remove (can do it in a parking lot easily in 15 minutes off and on if nice weather and a couple of tools and usually if you ask, the facility will allow you to do it) and replace.

All of this entire post is 100% incorrect information. The car runs ON THE BATTERY. The alternator is nothing but a battery maintainer and keeps the reservoir (battery) full. Without a good battery, nothing in the car will work correctly and HERE'S a test. Remove the battery and make the car run. You'll have to hook up jumper cables to someone else's car just to start it, and generally you'll wreck their alternator too. Try to drive it down the road and see what happens-it will not go very far and you'll see the alternator burn up from the smoke and sound coming from the engine bay.

 

Remove the alternator and put in just the battery and start the car and drive it for a couple of hours until the battery finally goes down too far to continue to power the electrical system in the car. Replace it with another fresh battery, and you're on your way again until that one goes down.

 

After you replace the alternator again because you just destroyed the first one by running it at 100% capacity and destroying the diode trio inside, then put a fully charged battery (12.6V) back in, and find out that it's the battery that keeps everything alive.

 

This continues to come up again and again. The alternator does nothing except charge the battery while the car is running. An average usage of amperage for most vehicles in normal weather is anywhere from 60-80 amps of continuous draw. The alternator generally runs from 80-105 amps on most normal vehicles (not including ambulances or commercial vehicles or highly modified vehicles with huge stereos, etc.) and it runs at about 60% capacity when it goes down the road at higher rpm. When you turn on more accessories, the ECM senses this and tells the alternator to turn up the juice and then moves to replace it, but there is no ass behind the amperage until it reaches the battery and relies on it's capacity and depth.

 

I taught this very subject-electrical and electronic system diagnosis and circuit voltage drop testing for several years at the installer level and also at W/D seminars, and believe me, there is no bigger myth in automotive than the one about the alternator being what runs the car. Again, it does nothing except maintain the battery at it's capacity.

Thank you for all the info, and the way you explained it (props on the "testing" procedure) makes complete sense to those of us without the in depth knowledge. There is ALOT of bad info out there saying the alternator runs your car when your engine is on, or at least the verb-age suggests that to the untrained reader. My car did die, twice, at lights and after replacing the battery and with the same weather conditions it's been running fine. Thanks for your time and patience in explaining the systems of our cars, I love learning more and more about this hunk of metal hurtling me down the road!

All of this entire post is 100% incorrect information. The car runs ON THE BATTERY. ……………...An average usage of amperage for most vehicles in normal weather is anywhere from 60-80 amps of continuous draw………………………..

If the battery "runs the car", then all current in the electrical system must pass through the battery. A simple test with a clamp style ammeter placed on the negative battery cable will show that the battery does not run the car. With a fully charged battery, and the engine running, you can have all the seat heaters, window heaters, and headlights etc turned on, and you will only see 1-2 amps on the negative lead of the battery. That is the charging current going through the battery. When you place the ammeter clamp on the alternator cable, you will see the total current of 20A-80A or higher. All the current runs through the alternator, not through the battery. The battery is wired in parallel with the alternator, not in series with the alternator. The only time you will see all the current going through the battery is when the alternator is not running.

As it says in the Bosch Automotive Handbook, 8th ed., page 948:

"……During vehicle operation……………….the ignition, ……………….the control units,…………...the lighting,……….and other equipment have to be supplied with power. The alternator supplies the required electrical power for these components and also to charge the battery……"

If the battery "runs the car", then all current in the electrical system must pass through the battery. A simple test with a clamp style ammeter placed on the negative battery cable will show that the battery does not run the car. With a fully charged battery, and the engine running, you can have all the seat heaters, window heaters, and headlights etc turned on, and you will only see 1-2 amps on the negative lead of the battery. That is the charging current going through the battery. When you place the ammeter clamp on the alternator cable, you will see the total current of 20A-80A or higher. All the current runs through the alternator, not through the battery. The battery is wired in parallel with the alternator, not in series with the alternator. The only time you will see all the current going through the battery is when the alternator is not running.

 

As it says in the Bosch Automotive Handbook, 8th ed., page 948:

"……During vehicle operation……………….the ignition, ……………….the control units,…………...the lighting,……….and other equipment have to be supplied with power. The alternator supplies the required electrical power for these components and also to charge the battery……"

You can believe whatever you wish and you can attempt to argue and try to justify your lack of understanding however you choose, but the absolute indisputable fact is that the battery is what the car operates on. The battery is the reservoir, the battery is the actual heart of the car. Every single electrical system on a car is designed around the actual battery and it's capacities. The alternator is designed for that particular vehicle to be able to maintain that particular battery reservoir so that the operation of all electrical systems is able without causing any of them to suffer due to usage of the available current (amperage) the way AC current does.

These are absolute facts and have been ever since cars with standalone electrical systems have been built and whether they had a generator or an alternator, makes no difference. The car is designed around the battery-simple engineering.

Your statement above is so blatantly incorrect, that I can't even begin to say anything without destroying you. I won't do that. Suffice it to say that ALL of those components draw direct current and they draw double digit amperage and that amperage adds up exponentially and at any given time, the charging system will be attempting to put back into the battery enough to maintain the battery at whatever the required cranking amperage is. Your statement cannot allow a correct diagnosis of the problem because it's based on completely incorrect assumptions and not any fact.

Simple understanding of how incorrect your statement is easily seen in that there are no fuses in the fuse box that are 1 or 2 amps. Each system is designed, as is each electrical system in a home, to have a certain nominal amperage load applied without exceeding the capability and capacity (wire gauge and number of conductors within the sheath) of that system and if that load is exceeded, and there were no place to have a controlled circuit shut off (fuse or circuit breaker), then the system itself would overload and cause the conductor (wire core) to overheat enough to actually cause a fire (as anyone that works on cars has seen with a melted wire within a wiring harness loom-caused because of a short circuit from the actual power source to ground somewhere before the fuse location and it allowed it to overheat and melt. As per the attached photo.). Take each of these systems you mention above and look at the fuse capabilities/failure points.

Simply put, whenever any of these systems are on, each system draws it's nominal current at the same time and there must be an amperage reservoir available to operate these systems, taking into account voltage drop and amperage loss at each connection (master plug, switch, component plug, component operational mechanical pieces) and amperage is the actual current on a direct current system.

These systems, drawing their nominal amperage, continue to mount exponentially on top of each other and in many cases, you have 70-80 amp continuous draw from the battery if you are running all of your systems. Ignition alone draws upwards of 20 amps continually when the vehicle is running. The battery has capacity to hold several hundred reserve amps due to the plate design and because of that design, it discharges from it's capacity very slowly. The alternator refreshes that capacity basically at the rate the amperage is distributed from the battery (as per the ECM reading each and every circuit thousands of times per second and instructing the alternator what to do) and the entire system is a big circle (positive output through the entire operating system and components and ground return system) and all is happy.

To make it as simple as possible-THE BATTERY MUST BE IN GOOD OPERATING CONDITION, FULLY CHARGED AT 12.6 VOLTS, HAVE GOOD CONNECTION POINTS, AND BE MAINTAINED BY THE ALTERNATOR FOR THE VEHICLE TO OPERATE CORRECTLY. NO BATTERY-NO OPERATION.

Some reading references for you:

http://www.howacarworks.com/basics/how-car-electrical-systems-work

http://randysrepairshop.net/testing-for-battery-drain.html

http://www.autotap.com/techlibrary/diagnosing_battery_charging_iginition_system.asp

http://www.hotrod.com/how-to/additional-how-to/0804rc-electrical-current/

Excellent information in this article:

http://www.madelectrical.com/electricaltech/howitworks.shtml

All of this entire post is 100% incorrect information. The car runs ON THE BATTERY. The alternator is nothing but a battery maintainer and keeps the reservoir (battery) full. Without a good battery, nothing in the car will work correctly and HERE'S a test. Remove the battery and make the car run. You'll have to hook up jumper cables to someone else's car just to start it, and generally you'll wreck their alternator too. Try to drive it down the road and see what happens-it will not go very far and you'll see the alternator burn up from the smoke and sound coming from the engine bay.

 

Remove the alternator and put in just the battery and start the car and drive it for a couple of hours until the battery finally goes down too far to continue to power the electrical system in the car. Replace it with another fresh battery, and you're on your way again until that one goes down.

 

After you replace the alternator again because you just destroyed the first one by running it at 100% capacity and destroying the diode trio inside, then put a fully charged battery (12.6V) back in, and find out that it's the battery that keeps everything alive.

 

This continues to come up again and again. The alternator does nothing except charge the battery while the car is running. An average usage of amperage for most vehicles in normal weather is anywhere from 60-80 amps of continuous draw. The alternator generally runs from 80-105 amps on most normal vehicles (not including ambulances or commercial vehicles or highly modified vehicles with huge stereos, etc.) and it runs at about 60% capacity when it goes down the road at higher rpm. When you turn on more accessories, the ECM senses this and tells the alternator to turn up the juice and then moves to replace it, but there is no ass behind the amperage until it reaches the battery and relies on it's capacity and depth.

 

I taught this very subject-electrical and electronic system diagnosis and circuit voltage drop testing for several years at the installer level and also at W/D seminars, and believe me, there is no bigger myth in automotive than the one about the alternator being what runs the car. Again, it does nothing except maintain the battery at it's capacity.

This does not make a lot of sense. Both the alternator and battery are power sources. As long as the power source can supply the necessary amperage and voltage to the load neither should suffer any damage.

In your example the car requires (draws) 60-80 amps and the alternator can supply 80-105 amps. As long as the alternator can supply the necessary amperage, which in your example it can, then there should be no harm to the alternator. It's when the load attempts to draw more current than the source can provide that damage occurs.

Given this it seems perfectly reasonable to me that the car should run fine without the battery. I am interested in hearing how the alternator would be damaged without a battery present.

This does not make a lot of sense. Both the alternator and battery are power sources. As long as the power source can supply the necessary amperage and voltage to the load neither should suffer any damage.

 

In your example the car requires (draws) 60-80 amps and the alternator can supply 80-105 amps. As long as the alternator can supply the necessary amperage, which in your example it can, then there should be no harm to the alternator. It's when the load attempts to draw more current than the source can provide that damage occurs.

 

Given this it seems perfectly reasonable to me that the car should run fine without the battery. I am interested in hearing how the alternator would be damaged without a battery present.

Please go ahead and run your car without a battery and report back the results. I would love to hear how it works out for you.