Battery 01 C2

I put an Autozone battery in the car last year some time and I noticed the other day when I drove it that cranking was slugglish. By the end of the day it was dead. (I was at my Barber and the conversation was basically "Nice Porsche! Thanks, wanna give me a push?") If it's the battery, what are you guys running? I hear people discuss lightweight batteries but have never really looked into them. The car is currently driven usually once a week (I had a trickle charger but cant seem to locate it) so Id like a good battery that wont continually go flat on me. Id prefer not to spend hundreds and hundreds on a battery. Is there a good bang for the buck out there? My cheapo Autozone battery clearly wasnt.

Interstate AGM MTX94R/H7 Its an AGM battery with a 36 month (3 year) FREE replacement warranty! NOT a prorated warranty! Retail is $225.00 but they can be had for under $200

U need to determine if the battery is not holding a charge or if the battery is not getting a charge. While the car is running u should see around 14-14.4v off the alternator and similar at the battery terminal. The wires from the alt to the starter r a know issue with these cars and yours may be bad.

I highly recommend the AGM from Bosch

I have an Interstate in mine that is 8 years old. I've been wanting to proactively replace it for a long time, but it still works great, even when the car sits idle for a week or two. I don't know which model it is, but I've always had good experiences with Interstate. Has anybody done any weight comparisons for 996 batteries -- particularly the actual weight of AGM batteries versus lead acid?

I got an H6 AGM battery from AutoZone to replace my 6 year old H6 DieHard AGM battery. Weighs a ton but I don't care about that. Works great. They are located within walking distance so I figure it is just a walk, swap and replace deal. I can live with that. There are like only 5 battery manufacturers anyway. Did some research. Duralast AGM to their specific specifications. And the sticker on it says "Made in Germany"....go figure.

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I have been running the same Duralast for about 10 months as well. No issues at all, even in the Vegas heat, where batteries typically last between 1-2 years. It comes with a 3 yrs full replacement warranty, so I don't mind replacing it if needed. I put the same battery in the gf's (ex now) in January as that's what it called for. No issues there either.

I've had the best luck with Interstate batteries in my various sports cars. A single Interstate battery (not sure of the model) lasted me about 8 or 9 years in my 996. I've had a NAPA battery in my 996 (again, I'm not sure of the model number) for the last 3 years and it has been going strong. I typically keep a battery maintainer on the car when it sits for more than a couple of weeks, which is often during the winter months.

The Varta DH Audi OEM battery (000-915-105-DH) (H7) is a good replacement battery, that looks factory and has the vent hook-up just like the Porsche battery. It's a German made battery that can only be gotten from Porsche/Audi dealership as they are not sold in the retail environment in the USA. Although they are handled/distributed by Interstate (owned by Johnson Controls) they are a European company/manufacturer. We were using the DH Audi battery as a replacement battery for Porsche for the Porsche dry-storage battery because it cost was so much less and was a good quality OEM like battery. Our local Interstate distributor actually relabled the DH battery for us to sell retail and have the Interstate warranty instead of the "Audi warranty"..The Porsche dry-stored battery also had to be filled with electrolite then recharged before install (making a hazzard and time consuming process, although dry-storage makes for long "shelf life").. We were very pleased with the Varta DH as a Porsche replacement for quality and longevity, but like all batteries not regularly used, they need to charged periodically to keep from early failure.

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I too have 5+ year old Interstate. I have a brand-new Optima AGM waiting and just sitting in my garage waiting for the Interstate to die. But it just refuses to die. The 996 starts right up after 3 weeks of sitting around with the alarm armed.

There are only three manufacturers of car batteries in the US that fit our cars. Johnson Controls (sells to most Walmart stores, Autozone, Advance, Interstate, etc.), Exide and East Penn (other Walmart, O'Reilly's). There are a couple of specialty manufacturers and a couple of Korean manufacturers but you will likely not see one of those for sale unless you are shopping at Menards. What I recommend is normally Interstate simply because they have a good nationwide warranty. Same with Advance Autoparts. Also if you go online, Advance normally has a 20% off coupon for a new customer - I used this in my diesel Jeep Grand Cherokee (same battery as our 996) and it saved me $40. The dealer batteries (I think) are East Penn - they have the OEM contract for BMW and MB for plants in the US. But really, it does not make that much difference. If the OP's battery failed in a year, it should still be covered under warranty - I'm pretty sure that the H6 batteries have at least 24 month free replacement from most retailers. AGM is fine, but probably not really necessary. Likely it will weight slightly more than a standard battery. There are lithium lightweight options but they would be very expensive - may make sense for a track car, but no benefit for a normal daily driver. If the car is occasional use, keep a trickle charger on it - batteries like to stay fully charged and do not do well if they are left in a partial state of charge for extended periods of time. Daryll

Awesome advice here guys. Forgive my ignorance, but whats AGM?

AGM = Angry German Machine. or maybe Absorbed Glass Mat. I put one in my car about 3 years ago - the Bosch Platinum Series AGM Battery Group Size H7/L4/94R from Pep Boys. My car sits sometimes for 10 days or more and I've not had any problems, even being in the North East in a detached, unheated garage. Check the Pep Boys site. Sometimes they give a nice discount if you order online and then pick it up. The site might say it doesn't fit your car but it does. Mine didn't come with a vent tube. I pulled off the one from the old battery and put it on the new one. I don't know if it's necessary.

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There are three main types of batteries "wet cell" "AGM" and "Gel Cell". Wet Cell are your standard type battery with lead plates and electrolite in between. Most all nowadays are "sealed lead/acid" and VRLA (valve regulated lead/acid) and do not require to have anything "added" over time. AGM are Absorbed Glass Matt (sponge), that have a sponge in between the lead plates to hold the electrolite. This helps a bit to keep from having flakes come off the lead plates and shorting the battery, but comes at a cost. Also is not good for very rough off-road as the sponge will actually rub the plates and cause wear. Gell Cell are just like the name emplies, the electrolite in between the plates are in a gell form and can be mounted in any way (sideways ect), and are recommended for off-road rough terrain, but is also the most expensive of the three. These are the three main types of lead/acid batteries, then of course you have the lithium-ion batteries, very powerfull, light weight, and expensive.

The benefit to AGM is that it will provide higher CCA (Cold Cranking Amps) in the same size case. But the drawback is that there is less free electrolyte (acid) so the battery is much more sensitive to overcharge, and will not last as long if it is abused. Also a AGM battery is much more temperature sensitive - you would not want to put it under the hood of a car next to the engine, but in our Porsches no problem in the frunk. Gel would not typically be used in a starting application - only deep cycle. Standard flooded batteries or AGM will both work fine in our cars as long as the charging voltage is good (should be around 14.1 - 14.2 volts on charge). AGM also costs more than standard flooded batteries but that cost differential is decreasing as all three main manufacturers are moving more towards AGM for new cars with stop-start. My BMW with stop-start came from the factory with an AGM battery - they perform much better in repeated start applications. The next new thing that you will see soon is EFB - enhanced flooded battery - that will work well for start-stop but will handle under-hood temperatures. Again, not necessary for a 996 but will be a less-expensive option than an AGM battery in the next year or two. Daryll

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Great info! Based upon the above, independent of price, would you pick AGM or flooded for: 1) a 996 driven regularly 2) a 996 driven only on weekends and mostly stored during winter

I would recommend the AGM batteries for both scenarios. The old lead/acid batteries off-gas corrosive fumes, thus the little hose you attach to the vent on the battery. The newer AGM's do not do this and can be installed in a confined space. Newer technology, better technology...adapt and move on. They really are powerful and do not need any maintenance.

IMHO, AGM is well worth the money . Less prone to sulfation. Overcharging should not be a concern with the 996 charging system. https://batteryuniversity.com/learn/..._glass_mat_agm

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Most of the new "wet cell" batteries are either SLA "sealed lead/acid" or VRLA "valve regulated lead/acid" and are considered "maintenance free", (no need to add distilled water). they do have a vent line but it is for extreme conditions/overcharging. The AGM's do usually have a higher cranking amps, but give up amp hours. This is a product of the plates design, number and size of the plates determine the cranking amps and amp hours. AGM's are harder to manufacture and therefore cost more, no real magic, still lead and acid, just has sponges in it.

On all my vehicle's I run the Maxx Everstart from Walmart, very hard to beat for the price and warranty. under a hundred dollars for the H8 battery with almost 1000 cca and 3 year 100% replacement and prorated to 5 years. very easy to upgrade to the H8 battery, battery tray come out with couple bolts and place blind nut in the hole already there for H8 install. worse part of the whole ordeal was having to go into Walmart. LOL they even chain down these 50 lbs. plus batteries to prevent theft.

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Yes. A battery maintainer is a simple, cheap, easy way to help even an ordinary battery last a long time. Mine hangs on the wall of my garage near the driver's door. I made a longish cord so it's easy to plug into the 996 cigarette lighter. Your battery will thank you.

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Lithium-ion batteries are worrisome, due to the problem of overheating and fires during charging. (Boeing grappled with this issue on the 787 Dreamliner.) Lithium- iron - aka LiFePO4 - batteries have performance close to lithium-ion without the nasty charging issues. And they are less than half the weight of comparable lead-acid batteries. But definitely more expensive - though cost seems to be dropping.

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A number of people have made good recommendations for AGM for both of these scenarios. That is fine - a quality AGM battery will perform well for a long time. But - in my cars I use standard flooded batteries and just plan on replacing them after five years or so. The exception is my BMW with start-stop - will replace that with another AGM. Cost-wise it works out probably the same, and you have less concern of a dead car due to a battery failure. Today's batteries, both flooded and AGM, tend to fail quickly - they typically don't give a lot of warning - so replacing on a time basis makes some sense. This is especially true for a daily driver that you depend on to get to work. Either way, as others have said keep a battery maintainer on a car that is going to be parked for more than a couple of weeks and your battery will thank you! Daryll

I used a Costco battery for close to $130. I believe it�s an Interstate battery under the hood... An important part of choosing a battery is the born date. You want a battery that�s no older than a month or two if possible.

A lot of Nope and more nope .. and a theory of operating only 5 years and then preventative replacement is fine until a few last nine months. Warranty? At Z2 am in the rain who cares. Want an AGM thats quality and made in the USA - not just rebranded junk like a bosch and everything else?

I had great success with my Optima AGM battery years ago - lasted 7+ years and back then I didnt have a trickle charger! My 996 came with a Bosch which has been good so far but I do need to keep it maintained. I've got an Opima adaptor plate from Yellowdog motorsports over in the USA so when the time comes i'll use that + Opima red top. I did read some commentary around Optima moving their production to Mexico and the quality dropping - the one I bought was made in Mexico and lasted though. Maybe they send the good ones to Australia as its so expensive to get them over here haha!

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I have an Interstate from Costco. It�s been fine for the 12 months I have had it. I park for a week at a time at the airport and never have an issue. It has a vent hole too. I bought the shortest one since it is a bit lighter and smaller. The mounting plate has theee hole to choose from.

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You said it, the worst part is going to Walmart 😂. I️ go twice a year to buy Mobil 1 for another car. It�s a sh#%show indeed.

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In BMW's I find that most batteries don't last after replacement as most people don't realize they have an on board battery management system that must be reset after replacement. This system constantly monitors the condition of the battery based off its age and charges it accordingly. If the system is not reset it nukes the battery thinking its older. This system has been adopted by most manufacturers on late model cars now.

I got a 2012 328. It starts right up after 3 months parked with no trickle charger attached. It's battery monitoring system is great.

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I'm of the same mindset. I'm not always convinced that newer tech is better when it comes to batteries. I had Optima red tops and a yellow top gel and didn't like either (red tops couldn't handle being drained, yellow top (deep cycle) could handle being drained but lower CCA). I guess both would have been fine with a constant trickle charger, but I found flooded performed much better long-term. I'm happy to spend $50 or whatever additional for AGM, but not sure its long term durability is better (though cranking is clearly better). It sounds like AGM's for the 996 are heavier even though, theoretically, AGM should weigh a lot less. Our 996 is driven sporadically -- enough not to use a trickle, but it's not unusual for it to sit a week or two. It seems like flooded might be better for that scenario.

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Well this is my side of the fence...so I can add a few things.... To clarify Lithium-Ion does not define the type of Chemistry of the particular Lithium-Ion Battery you are using. "Lithium-Ion" is an umbrella term meaning any re-chargeable Lithium Chemistry based batteries, though the public usually thinks it means all Lithium batteries..... So a "Lithium-Ion Battery" can actually refer to any rechargeable lithium chemistry like (Lithium Cobalt / Lithium Polymer), Lithium-Iron Phosphate, or Lithium Manganese, etc. So you have to specify the chemistry if your talking about Automotive/Motorsports Batteries. Lithium-Iron Phosphate (Lifepo4) is what the companies like Antigravity Batteries (me), Braille, and others like Volt Phreaks use in their Motorsports Starter Batteries. So if you're interested in this type of Battery then it will be made using the Lifepo4 Chemistry which works and operates in the same voltage range as 12v Lead/Acid Batteries. And within that there are varying degrees of cell quality, and level of built-in protections in the form of a Battery Management System (BMS) on-board, and also how technologically advanced they are... for example our Antigravity Lithium Batteries have built- in Wireless Jump Starting, so you can never be locked out of your frunk or not be able to start your car if it has a dead battery. Simply press the provided Keyfob and the Antigravity Battery awakens with its reserve supply of power and can start your car or just provide the power to your system so you can operate the frunk to put it on a charger. As for Lithium being more Expensive.... that might not be entirely the case. For example yes the initial buy-in cost is more expensive... but in most all cases ( and depending if the lithium battery you buy has a full Battery Management System on-board) the battery will outlast the Lead Acid battery by twice the lifespan. The reasons for this first being an advanced Lithium battery has twice the rated cycles and more than a lead acid battery. Secondly, the advanced lithium battey has a BMS -Battery Management System that will not allow it to be over-discharged (the main cause of damage to any battery), over-charged, it also makes sure the cells are balanced when charging and discharging, it offers short circuit protections, and thermal protection so you get the longest life possible out of the battery. So,because the battery cannot really go outside it's set of defined parameters it has exceptionally long life and performance because it can't really be damaged by an accidental over-discharge like a lead acid battery. Then of course it has the massive weight-loss benefit... this may not be desirable to some but it is a definite positive factor when you can drop 35lbs just changing the battery in a car. So when you combine all that, YES it more expensive initially but then pays for itself with a number of benefits... for example one time using our Built-In Wireless Jump Starting could save you money and the value of not being stranded is pretty significant. Do it two or three times and it has paid for itself because unlike the lead acid battery the lithium battery won't be damaged by the over-discharge because it will put itself to sleep. Here's a link to the battery...we have different sizes to fit most all Performance Euro and American Cars. https://shop.antigravitybatteries.co...tive/ag-h6-rs/ You Tube

Update, took the battery and had it tested. It was fine just a little drained from something pulling it down. Charged it up and threw it back in. Im thinking back now to a night a few weeks back when all my warning lights faded in and out on the dash and this is feeling more like an alternator.

See my post #3. U need to check the alt and the wiring. There r known issues with the "y" wire to the starter. Do a search as there are alternatives to the factory wire that work better.

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Will do! thanks

When I got home today I got the multi meter out and the batter was weak, only pulling 10.6V so it wasn�t enough to turn the car over. Could the alternator cause that or does it seem like there�s a draw there? I disconnected the negative cable and it said it was drawing between 6.88 and 7.25 amps. I feel like that�s way high.

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Test charging system first.. Could be anything draining the battery ( even ignition switch not parking), but you can't test like that. Recharge the battery, crank and run engine, turn off, install in-line amp meter, without breaking connection,(20amp to 10ma). Takes up to an hour for all control units to go to sleep, usually 5-10 min. Battery drain should go down to about 30ma..

I bought a Bosch battery at Pepboys about 6 years ago which has a 36 months free replacement warranty. It seems that every 18 to 24 months it starts to not hold a charge as well. I take it to Pepboys, they test it, look at the date of manufacture and give me a new battery. I think I am on the third or fourth battery now. Kind of a pain but what the heck I change my oil much more often and have to pay for the oil and filter whereas the new batteries have been “free.” As long as they keep replacing the I’m happy.��

I recently had to replace my battery in a pinch and went with the Walmart H6 Everstart Max. Cheap ($120) and convenient. But tell me more about the "Know Issue" with the wires from the alternator to the starter? Every once in a while I get a no-start condition, I turn the key to start and no crank, reset the key and turn to start and it it will crank and start...Happens much less with the new battery. Maybe one out of 100 starts. Tiptronic. Also only seems to occur after warmed up. I was thinking ground or wiring connection issue somewhere along the line. Anyone else?

Seabass - any time that happens to me it�s because I didn�t get the clutch all the way to the floor.

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It it was charged when you started the trip and low when you finished, it seems like the alternator is definitely not keeping up. That current draw seems very, very high for parked -- was it still drawing that much later? It seems unlikely that two things are bad (unexplained current draw and alternator/voltage regulator defective). Maybe the current draw is even higher when running so the alternator can't keep up, though it's difficult to imagine what could draw that much without any signs. Or maybe a higher sustained current load caused the alternator to wear out. On the other hand, each battery cell puts out around 2.2 volts, so if you had a bad cell in the battery, it would probably drop you to around your 10.6 volt reading. It definitely seems worthwhile to have an expert with the right equipment figure out what's going on.

The battery is charging today on a trickle charge out of the car. When I get home today Ill test the battery before putting it back in and then test the alternator once its in and running. Im really hoping its the alternator but given that I cranked it with a fresh battery and pulled it out of the garage and back in then left it alone til the next day and it was dead makes me think Ive got a drain somehwere

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In the old days, you could pull fuses one-by-one to find out where the current drain was, but I don't know if that is such a great idea for newer cars with ECU's. The only thing I can think of that would draw that many amps without any visible sign is the rear window defroster. The defroster should shut off with the key, but if the relay is stuck then maybe it would stay on. There rear window would be slightly warm if that is the case.

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Tiptronic, I updated my post but thank you for the suggestion.

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Do you know whether it is a Bosch AGM or flooded cell type?

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Were you using the rear defroster that day? The more I think about it, the more that makes sense as the cause. If the defroster relay is fused, the interior defroster indicator light would still go out when you shut off the car, and it would not turn back on when you restarted it, but the defroster would keep running whether the key is on or off because the high-current supply side of the relay is stuck on.

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I don't think I've ever used it to be honest. definitely not lately, I live in Alabama. Though, this did seem to start after I got it our of the body shop, maybe they flipped something

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Def on the list to check now

Ok update. Haven�t had much time lately so today I had a few minutes and I jumped it off. Let it run for a few minutes and checked the alternator. Battery was showing 13.9-14.1 consistently with no ac or stereo on. After turning the car off the battery was only at 11.3 and I watch it tick down to about 10.5 before I stopped watching (about 30 secs). Thoughts? How do I test the cable that runs from the alternator to the battery?

I just had a battery replaced, thinking back a few weeks ago I should have realized that the engine was cranking slowly.... Sunday we were going to take a drive and have lunch along the beach... click.....click....click....DED....I looked up the battery, replacements they ran from $150 to over $200 OK, I can do that, wife says call and have it done Mr Macho man...you ain't as young as you used to be Called AAA and they would replace the battery for $180...so, they come to you, check the system with a computer, provide and install the battery, use a device that saves your programming, and give a 3 year replacement and 3 additional years of pro rated guarantee .. AND no breaking my back lifting a 50+ # battery out and bringing to back to the store for credit..... DEAL....CANT BE BEAT Listen to the wife....she's right.... And...if your battery is 5 or 6 years old just replace it,,,because you know it's "on it's way out" and it will generally leave you stranded at the worst possible time....cheap insurance....

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You really need to have a professional check it out because they have the equipment to identify the cause very quickly. Just about any competent that sells batteries can do that -- it isn't a specialized Porsche-specific process to identify the cause. If you have AAA, that would seem to be a good solution given the comments that they do analysis to figure out the cause before taking action. I assume with AAA you could choose to decline the battery replacement if you wanted to buy it somewhere else. If you have a dead cell in the battery, it will likely still jump start and show higher voltage due to the alternator output, but when when you shut off the car it will show voltage a little over 2 volts down. I would try disconnecting the battery from the car, then check the voltage. Then charge the battery while still disconnected and see what the voltage goes up to (if you have a faulty cell, it will stay low -- or maybe go to normal voltage but then drop down again with a moderate current draw). Previously you measured a current drain when the car was off (is that still the case?), but that would not affect your last scenario very much assuming you measured the battery immediately after shutting the car off.

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I took the battery out and had it tested and it was fine. Ill try your suggestion of charging it again out of the car and testing it. I think last time after it was charged I threw it in and it started the car without checking it.

Yea it kind of sounds like u have something draing the bat not a charging issue. U may need to get an amp meter and pull one fuse at a time untill the amprage drops off when the car is not running. No real easy way to find a random draw

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If it started on the battery alone last time after charging, you probably don't have a bad cell. You can measure voltage easily with a meter, but I don't think it's possible to measure amperage unless you have a serious meter (with battery cable size leads). You really to take the whole car and get the charging system tested rather than just having the battery tested.

He is getting over 14v when the car is running so its charging. The issue seams to be that something in the car is "on" with the car off and its pulling the battery quickly. This meter should work for dc amps. I think home depot and lowes both sell a version of this too. Meterk Digital Clamp Meter Multimeter 4000 Counts Auto-ranging Multimeter with AC/DC Voltage&Current, Resistance, Capacitance, Frequency, Diode, Hz Test, Non-contact Voltage Detect Amazon Amazon

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That is a very cool meter -- have not seen a clamp-on that does DC current. Still, I recommend a charging system analysis. I think Autozone does them for free. The symptoms don't really add up. That last showed that the voltage dropped immediately (if I understood his post correctly) after shutting off the car -- nothing can drain the battery that quickly without smoke involved I would think. If the voltage pops back up after removing the battery terminal, then maybe something is dragging it down, but I don't see how voltage could be dragged down without smoke somewhere. On the other hand, since he jumped it, rather than charged it, maybe the battery voltage was already low and he did not run it long enough for it to charge up (that would explain the result in OP's last update). A previous post stated that the it had a 7 amp drain when shut off, but even that heavy load would take a while to drop voltage down. If that 7 amp drain is still happening, I maintain my belief that it's likely that the supply side of the rear defroster relay is fused on (because that's the only thing I can think of that will suck up significant amperage without any detectible sign). All of this would be answered with a free analysis by Autozone or any other competent shop.

Ok so I charged the battery out of the car, pulled the rear defrost fuse, and put the battery back in. Would not start the car. I jumped it off and drove it for about 20 minutes. Checked the voltage running and it was now reading low 13s...not good. Turned it off and the battery read 10.5. Left it overnight and in the morning and it still read 10.5 so if there was a draw, it was the rear defrost. Doesnt seem like the alternator is doing its job so it�s coming out, which brings me to my current question...how in the HELL do you back this bushing off?? I�ve WD40�ed it to death and rethreaded the bolt a little and beat on it relentlessly trying to back it up some. Any tricks??

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What was the voltage of the battery after charging the battery out of the car before putting it back in the car? Why pull the alternator????? If it won't start without a jump immediately after charging the battery out of the car, the alternator is nowhere in that picture. It doesn't need the alternator to start and cranking doesn't turn the alternator enough to put out any voltage. Most likely the battery is bad given the inability to start the car on its own and the quick voltage drop. Each of the 6 cells inside the battery put out around 2.2 volts each. If the battery has a weak cell, it may show decent voltage under no load after a fresh charge, but then drop to close to zero when any heavy load is put on it. If something was wrong with the starter itself draining too much current, you'd probably have a difficult time jumping it as well. It's good that there is no drain after removing the defroster fuse. It's typically unlikely for 2 components (defroster relay and battery) to go bad at the same time, but if the defroster relay was stuck on, then multiple drain cycles could have killed the battery. I'm very confused why you don't take it to a shop for evaluation. Any competent battery shop will have the right equipment and be able to pinpoint the problem (battery, voltage regulator, cables, ground strap, alternator ...) in a few minutes. Usually the charge for that test is minimal or free. Pulling the alternator on a hunch seems like a massive presumption, especially since it doesn't explain why your battery won't start the car after a full recharge.

Alternator might be fine, as low 13s is just probably regulating the voltage - the battery might not be able to take much charge. The alternator is increasing a 10.5v to over 13, so that means it�s working. Any battery that�s been fully charged but still reads 10.5V is a bad battery. Especially if you charged it overnight with a trickle charger (0.75-2amps).

OP, peterp is correct…take it to Autozone and they can tell you immediately if it’s battery. Sidenote: If you do need to eventually take alternator out; PB Blaster (lots and soak it) on bushing, then whack and wiggle. Takes time and lots of seemingly fruitless hammer swings. Bushing doesn’t need to move much to be able to rotate assembly free. I just replaced my voltage regulator last week, because Autozone reader said it was the culprit...and it was.

Nothing worse than a dead battery...generally you get a warning...pay attention, having it checked is easy... I always use AAA, if it's really a gonner, they will have a new replacement at a good price...no fuss..

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I work long days and generally only have time to play with it at night. Plus chasing things down is half the fun! The battery was reading 12.3 after the charge. I had it tested when this all started and it was fine. maybe i should get a second opinion? As for the Alternator, there was an incident recently where all of my warning lights across the bottom of the dash went crazy and flashed on and off for about a minute while i was driving. that seemed very "alternator-y". If its not the culprit Ill throw it back in. I did uncover some bad pulleys in this process so I'll replace those as well while im in there. Mainly, I have 2 small kids (2 and 5 months) and a wife, so any time I can spend in the garage with the music on and a wrench in my hands is relaxing for me. "Can you bathe the kids tonight? I've got to figure out this car situation..." Most of my time in the garage is actually spent quietly staring at the wall.

Quotes source posts: 15857813, 15857813

12.3 volts after a full charge is not good, so if it was charged long enough with something stronger than a trickle charger, almost certainly the battery is bad. Trickle chargers are for maintaining voltage, they take forever and a day to recharge highly discharged batteries. If you used a trickle charger, that could explain the low voltage without the battery necessarily being bad (which would explain why it didn't start on it's own and could lend credence to an alternator or voltage regulator problem because the voltage dropped in use). If you used a real charger, the battery almost certainly is bad. The battery may have been fine then, but it is very possible that the battery was subsequently damaged as a result of the current drain issue. If the root problem does turn out to be a stuck rear defroster relay, that explains your initial issues, and it would have caused your battery to be severely discharged several times (the defroster is essentially a "controlled" short circuit, it's a lot more severe than something like a dome light being left on). Typical lead acid car batteries can't handle multiple deep discharges without being damaged. "Deep cycle" batteries (like those used in golf carts) are designed to handle discharges without damage, but they make lousy car batteries, so virtually all batteries designed for automative applications can't handle severe discharges very well at all.

Quotes source post: 15858027

That's what I was thinking but it was close enough so I wasn't sure. My charger supposedly acts as a charger and then switches over to a maintainer once fully charged. It's from Harbor Freight so I take that with a grain of salt

Quotes source post: 15857612

The battery showed 12.3 after initial charge and 10.5 after driving and turning the car off. It maintained that 10.5 over night

Quotes source post: 15858312

A fully charged battery after stabilizing will read exactly 12.6v. There are 6 cells at 2.1v each, a voltage of 10.5 after stabilizing is exactly what you will see if a cell is shorted, 12.6v - 2.1v = 10.5v

Hi guys, would definitely agree and lean towards that battery not doing so hot on this one. One thing some of you might be interested in to help monitor voltage and performance in a scenario like this would be one of our Bluetooth Battery Trackers. Essentially it will let you monitor your real time voltage without having to go to the battery and the tracker will keep a log showing you that voltage for up to 30 days by using an app on your cell phone. In addition you can set it to send you alerts for low voltage to let you know there might be problem. Lastly you can also perform charging and cranking tests to let you know how the system and battery is doing. Please feel free to check them out as there is an option for Lithium Batteries as well as for Lead Acid Batteries and feel free to let us know if you have any questions. - [email removed]

Quotes source post: 15857813

I'd rather be driving or at least spending quality time with my wife and kids...

Quotes source post: 15860200

we get plenty of quality time, don't worry

Quotes source post: 15858345

Good to know - thanks

so in the end, both the battery and alternator were bad. replaced both and Im happy again

Nick I Like the LOBSTER CLAW wheels...had them on a 997 that I had a few years ago...

Nothing like 2 different issues to really scew up a diagnosis.

Quotes source post: 15867719

Thanks. I originally set out to buy some OZ wheels but came across these lobster forks and decided to use them for a while. I always liked them. Ill probably swap them out in a few months

Quotes source post: 15867901

Couple that with my 2 year daughter old wanting to "help' me by moving bolts around the garage and it made for a pretty interesting endeavor