Battery question..........

[PQ]

Wasn't sure exactly where to put this so I'll just drop it in here. Hell, it probably would apply to our Camaros as well.

My sons Jeep started missing and chuging and lugging again. Last time it was the battery that I replaced and it ran fine after that. Took forever to figure it was the battery because it had enough juice to start the space shuttle. Never had even the slightest problem as far as the 'Low Voltage' starting that whines and dies when trying to start. I only did the battery because the battery light would come on my son said and it threw that code last time.

Well this time it threw a Bank 1 Sensor 1 O2 code. So I checked all of the wiring to make sure it was sound and then changed the O2 sensor. Fixed the code right away but NOT the problem of the Jeep sputtering.

NO BATTERY OR VOLTAGE CODES. In fact, no codes at all now.

So I ask my son if the battery light has been coming on again. He tells me yes, from time to time.

So I realize that the battery is probably bad again. I'm thinking it's the alternator causing this. So I run down to have it checked. The battery reads bad. The alternator reads good. So I buy a battery and put it in.

This is the third battery I have put in it. The very first one just went dead juice and all but something seems to be causing them to go bad. OR just a super crazy coincidence.

Now, the battery I bought 4 months ago when this happened last time I put in Bonnies Vette and the one from the Vette into the Jeep so this one that just went bad in the Jeep again was from Bonnies Vette. But it was fine when we put it in the Jeep. (I didn't want to put the brand new one in the Jeep over the Vette)

So the Jeep has a brand new battery and is running FINE. No codes.

My questions are these:

1) How can a battery be bad, causing the Jeep to run funky, yet have full juice to start the car like normal?

2) Is it possible that my alternator IS IN FACT bad but just not at all times? (reading good when he ran the test but bad at times)

3) Could this be a computer problem?

[90503]

I'm thinking it's possibly an intermittent short with the positive cable or wiring...If it was ground you wouldn't be charging, but if hot wires are shorting or going to ground, who knows what goes hay-wire...good luck...

[Russell James]

The sputtering possibly killed the O2. Carboned it up from all the misfires.

Now to find the real cause of the sputtering and dead batteries.

A couple things I'd look at.... did they really test the charging system thoroughly, or just went ... yup the alternator is charging.

It could be overcharging and killing the batteries. Too much corrosion at a connection can cause that. Such as corroded or loose battery cables. Corrosion or looseness at the wiring connection to the alternator.

Pull the wiring connection at the alternator. Any signs of heat/corrosion/looseness at the alternator wiring connection?

Changing the battery cables would be a good idea if it's an older vehicle. Sometimes the corrosion can be hidden under the insulation.

And a tech that really knows how to do a good starting and charging system test with a VAT 40 type of tool, and also do a parasitic drain test and see how many mili amps are drawing when the vehicle is off.

Try to find where some of the main body grounds are, and go through and retighten as many grounds as you can find.

If all the basics have been gone through, and it's not overcharging now.... maybe just some bad batteries?

If the battery light ever comes back on or the sputtering returns, put a scanner on it and see what voltage the ECM is seeing compared to what the battery voltage actually is.

[its a syn]

PQ= Camaro, Bonnie= Corvette, Son=Jeep? Didn't he learn anything !!! Just kidding I keep saying a Chrysler vehicle won't ever see my garage again and low and behold one somehow strays in from somewhere. Seems like everyone I had has had some kind of elecrical funk problem with it. Good luck sorry I couldn't help ya.

[Jason@JacFab]

+1 on the alternator overcharging... That's the first thing that came to my head...

[PQ]

Originally Posted by Russell James

The sputtering possibly killed the O2. Carboned it up from all the misfires.

Now to find the real cause of the sputtering and dead batteries.

A couple things I'd look at.... did they really test the charging system thoroughly, or just went ... yup the alternator is charging.

It could be overcharging and killing the batteries. Too much corrosion at a connection can cause that. Such as corroded or loose battery cables. Corrosion or looseness at the wiring connection to the alternator.

Pull the wiring connection at the alternator. Any signs of heat/corrosion/looseness at the alternator wiring connection?

Changing the battery cables would be a good idea if it's an older vehicle. Sometimes the corrosion can be hidden under the insulation.

And a tech that really knows how to do a good starting and charging system test with a VAT 40 type of tool, and also do a parasitic drain test and see how many mili amps are drawing when the vehicle is off.

Try to find where some of the main body grounds are, and go through and retighten as many grounds as you can find.

If all the basics have been gone through, and it's not overcharging now.... maybe just some bad batteries?

If the battery light ever comes back on or the sputtering returns, put a scanner on it and see what voltage the ECM is seeing compared to what the battery voltage actually is.

Good stuff.

Ya, when I went through all the wiring with the O2 I went through the fuse panel, and the battery wires and all that I could get to to see without removing anything. No corrosive wires, connection or anything that I could find. The O2 had very little fresh carbon on it. And it's the upstream sensor. Sure had a rich mixture smell though. Before we put the knew battery in anyway. So you may be right.

The dude who tested it put a meter on the battery with the car off to tell me the battery was bad. He had me turn the car on and showed me how the alternator was reading good. But you also may be right about that. Could be just the alternator putting out the right current but still bad in some way?

Just a few months ago I had to pull the heads (overhead cams ) and change out the head gaskets because my son overheated the SHIT out of the car when it was drained of ALL coolant one night. I suspect I still have a very small head gasket leak. But only into a water jacket. So I'm probably on borrowed time anyway. But I'm not possitive. I did a compression and leakdown test and showed one cylinder 12% lower than most others. The air was coming from the crank case so rings. Might not have a head gasket leak at all but only a water leak in a hose or something. Loses water about 32 oz. per tank of gas.

Anyway, it got REALLY hot that night so maybe the alternator sustained some wiring damage? I had to take the AC, alternator, power steering pump etc......... off when I did the gaskets. I didn't notice any connection problems or anything that could be hurting it as far as that goes.

How can a battery be bad and yet hold a full charge to start the car?

Originally Posted by its a syn

PQ= Camaro, Bonnie= Corvette, Son=Jeep? Didn't he learn anything !!! Just kidding I keep saying a Chrysler vehicle won't ever see my garage again and low and behold one somehow strays in from somewhere. Seems like everyone I had has had some kind of elecrical funk problem with it. Good luck sorry I couldn't help ya.

I'll never own another Chrysler. Not just because of the car but the work and dealership bullshit that I have experienced.

Originally Posted by RacnJsn95

+1 on the alternator overcharging... That's the first thing that came to my head...

What regulates the charge? The battery, computer, or alternator?

[PIPE]

PQ, my brother was dealing with a similiar issue on his step-son's jeep. Kept throwing a code of that similiar status. It ended up being in his words ( the fireing rail over the spark plugs) I'm assuming without actually looking at the engine , that he's meaning the COIL part of the older coil and plug days if that makes sense lol

[strych9]

What year is the Jeep? Most newer vehicles are regulated by the computer.

Usually an intermittent driveability problem caused by the battery can be attributed to a broken connection between the plates inside the battery. Is it mounted securely? A dumb question, I know, but has to be asked.

Check all of the grounds thoroughly. Jeeps are famous for loose and insufficient grounds. Another thing that's common is for the alternator to create goofy electrical interference that screws up how it regulates voltage. Check wires and routing near it.

If grounds and wiring are good, an alternator would be the logical start.

[PQ]

Originally Posted by PIPE

PQ, my brother was dealing with a similiar issue on his step-son's jeep. Kept throwing a code of that similiar status. It ended up being in his words ( the fireing rail over the spark plugs) I'm assuming without actually looking at the engine , that he's meaning the COIL part of the older coil and plug days if that makes sense lol

I ruled that out the last time the battery went bad. I tested the coil packs.

My sons is a Liberty so I believe at one point there was a plastic tube that the harness to the firing clips went to before I took it off.

Then when I put the new battery in it, last time and this time, all of the symptoms went away immediately and it ran great.

Part that I most want to figure out is how can a battery be bad but stay fully charged charged?

[PQ]

Originally Posted by strych9

What year is the Jeep? Most newer vehicles are regulated by the computer.

Usually an intermittent driveability problem caused by the battery can be attributed to a broken connection between the plates inside the battery. Is it mounted securely? A dumb question, I know, but has to be asked.

Check all of the grounds thoroughly. Jeeps are famous for loose and insufficient grounds. Another thing that's common is for the alternator to create goofy electrical interference that screws up how it regulates voltage. Check wires and routing near it.

If grounds and wiring are good, an alternator would be the logical start.

2003 Liberty.

NO, it was just sitting in there. The first one was mounted securely though. This one was much smaller from Bonnies Vette so it just sat in there. THIS newest one is not mounted either as I misplaced the bracket. Probably in the garage somewhere.

How do I check the alternator for sure? The guy at.......... O'Reilley told me it was good. lol

He did mention the Computer could be the problem regulating the system too.

[strych9]

Originally Posted by PQ

2003 Liberty.

NO, it was just sitting in there. The first one was mounted securely though. This one was much smaller from Bonnies Vette so it just sat in there. THIS newest one is not mounted either as I misplaced the bracket. Probably in the garage somewhere.

How do I check the alternator for sure? The guy at.......... O'Reilley told me it was good. lol

He did mention the Computer could be the problem regulating the system too.

On that vehicle the charging system IS regulated by the PCM. Unless the PCM is having issues, if your connections are tight at the alternator then it's likely regulating properly.

The battery might be bouncing around and breaking the plate connections internal to the battery. It really doesn't take too much jostling to damage an unsecured battery. They are designed to take vibrations well, but the shock of bouncing around ruins them.

As for the alternator, to check for the "weird interference" that I referred to earlier requires an oscilloscope. It can find the inconsistent output that might be throwing the voltage regulation off, causing an overcharge condition. Normally though, you would see evidence of some acid overflow from the battery vent if overcharging had been present.

Hope this helps.

[KRich2587]

you need to put the loads on to test the alternator radio lights everything all electrical loads on and raise rpm check charging voltage best done with vat 40 type machine that will load the system and read amps could also have excessive ac voltage outputting from the alternator just checking with a meter is no good

[Redemption]

internal short inside the battery, overcharging. Both good theories.

[PQ]

Display is messing up now.

Car runs great. No problems at all. But we realized that the drivers info like MPGs and is way off. Showing 1 to 3 mpg which we know is not right. That's after a reset.

Probably non-related. Freaking POS.

Originally Posted by strych9

On that vehicle the charging system IS regulated by the PCM. Unless the PCM is having issues, if your connections are tight at the alternator then it's likely regulating properly.

The battery might be bouncing around and breaking the plate connections internal to the battery. It really doesn't take too much jostling to damage an unsecured battery. They are designed to take vibrations well, but the shock of bouncing around ruins them.

As for the alternator, to check for the "weird interference" that I referred to earlier requires an oscilloscope. It can find the inconsistent output that might be throwing the voltage regulation off, causing an overcharge condition. Normally though, you would see evidence of some acid overflow from the battery vent if overcharging had been present.

Hope this helps.

Can the battery swell? Seemed like it was swolen.

But what about making the car run like crap. How can a battery with a full charge do that?

Originally Posted by KRich2587

you need to put the loads on to test the alternator radio lights everything all electrical loads on and raise rpm check charging voltage best done with vat 40 type machine that will load the system and read amps could also have excessive ac voltage outputting from the alternator just checking with a meter is no good

I already gave them the battery as a 'core' but I'll make sure to take it to a place like that.......... next...?...... time.