Battery woes, please help!

Hi guys, So my battery's dead. I haven't tested the battery yet, but at ignition it's showing 11 volts when it's normally much higher. Engine turned over a few times & then tick tick tick. I want to run over to walmart and pick up a new battery. I am aware that some on this board use walmart batteries. What model did you guys use? Thanks!

Alright, looks to be Ever start #48. I'll post back after the install!

Was it showing 11 volts when it was running? I would get it running first before you buy a battery. Once it's running disconnect the battery, if the car dies the problem is your alternator not the battery. I it keeps running the battery is bad.

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Too late I guess but for the next time one thing you can do is take the old battery with you and match it up to one that is close to the same CCA and AH and as close to the same size as the orignal/old battery. Also, note the location of the battery posts and the vent tube fitting. In some cases a larger battery larger as in a longer battery is a drop in (my experience when I replaced the battery in my Boxster). When you remove the old battery check the bottom of the battery box for other hold down holes and see if the hold down clamp bolt threads into the hole. Take an accurate measurement of the distance the battery can 'grow' and still fit. If it does and if find the proper capacity battery that is longer but still can fit, you can buy the larger/longer battery. Avoid if at all possible getting a battery that is a loose fit or requires hacking to fit and connect. Sincerely, Macster.

Hi everyone, Thanks for the replies. I got the walmart battery(Ever Start #48), car starts fine now. This is a smaller one, but was also a drop in thanks to the movable hold-down plate(thanks porsche!). I am hesitant to test for the alternator with the car running. The battery is running many amps of current, and I'm worried about contact bounce when I go to disconnect it with the engine running. Is this a safe way to test if the alternator is at fault? Another thing, when I got back from walmart, battery voltage had dropped below 10 V when it was at above 11 before...

It's safe, Just disconnect the negative terminal.

Ok, just got back from that. Car runs fine without the battery. After awhile the rpm at idle bumped up a bit after the lights started flickering at idle, but it ran fine for about 5 minutes before I shut it off. So it was definitely the battery, but I am having a new problem. With the new battery, the voltage level is pegged at just under 12 volts, and after awhile the car gives me a battery warning message. The battery light comes on, then goes away almost immediately. This keeps happening every few minutes. The car starts & drives fine though. I'm suspecting either a) it's just a lower voltage battery(12 volts). It provides ample starting voltage(~ 14 volts). or b) I could be getting a voltage leak somewhere. or c) voltage regulator on the alternator, which now that I think about it, makes the most sense. Thoughts?

Check the connections at the battery make sure they are clean, and check the grounds on the car. The new battery probably isn't fully charged. so you probably need to drive it for a bit(with out the lights and radio on) to get it charged up. If you have a volt meter (hand held) you can check the battery voltage to see what it is.

On the left side of the instrument cluster is a voltmeter. What is the voltage with the key on and car not running? Should be at 12 volts What is the voltage when you engage the starter? Can momentarily drop to 10.5-11 volts What is the voltage when the car starts running? Should go to 14 volts and stay there for a few min If it doesn't go to 13.5-14 volts after starting or if it(voltage) fluxuates a lot up and down,or stays down with car running, it is the alternator OR the voltage regulator that is built into the alternator.

Voltage is about 12V before starting. Voltage comes to about 13 when starting Voltage drops to about 11.8 when driving around. With the engine turned on, and the battery disconnected, the voltage fluctuates from 10.5-11.5 volts, so right now I am suspecting the voltage regulator on the alternator. I'll try to have my mechanic look at it tomorrow morning.

Good luck! Any time I have ever seen someone pull a battery cable off of a running engine the alternator has been fried . That is the reason a battery cutoff switch in track cars has a load. To protect the alternator and or regulator when the switch is opened (shut off). You can also fry many of the electronics in the car.

http://www.troubleshooters.com/dont_...ct_battery.htm Don't Disconnect the Battery with the Engine Running Copyright (C) 2005 by Steve Litt Steve Litt is the author of Troubleshooting Techniques of the Successful Technologist and Rapid Learning: Secret Weapon of the Successful Technologist. Some day a well meaning mechanic or naive jump start expert will attempt to disconnect your battery with the engine running. If you value your car and your money, don't let him! -------------------------------------------------------------------------------- The man from the road service thinks he's being helpful. After he can't jump start your car, he puts in his own known good battery and starts your car. So far so good -- your battery was definitely either run down or bad, and he's proven it. Now he decides to "test" your alternator by disconnecting the battery. After all, the car's ignition should be able to run on just the alternator's power alone. Wrong! The moment he disconnects either lead from your battery, it's entirely possible he caused thousands of dollars in damage. Here's why... Your battery does more than just yield electricity. It also shorts AC, spikes and transients to ground. Removing the battery from the circuit allows those spikes and transients to travel around, endangering every semiconductor circuit in your car. The ECU, the speed sensitive steering, the memory seat adjustments, the cruise control, and even the car's stereo. Even if your computers and stereo remain intact, in a great many cases removing the battery burns out the diodes in the alternator, necessitating a new alternator. If disconnecting the battery interferes with the voltage regulator's control voltage input, it's even possible for the alternator to put out hundreds of volts, frying everything. Even the initial premise was wrong. If you disconnect the battery and the car conks out, you don't know if it conked out due to insufficient alternator current, or whether the resulting transients caused your ECU (the car's computer, which controls fuel mixture, timing, and much more) to spit out bad data, shutting down the car. Nobody should EVER run your engine without a battery. And yet when you tell them not to, they'll roll their eyes. "I'm a professional. I do this every day. It's fine!" They'll sound so authoritative. So commanding. So intimidating. But they're wrong. The problem, of course, is that disconnecting the battery doesn't always damage something. It does it only sometimes. Less experienced jump start professionals and automotive technicians figure if they got away with it a few times, it must be OK. Don't let them do it on your car. When you call for roadside service, or take the car in for possible electrical problems, or have your battery and charging system checked at a "battery shop", give them this letter.

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Wow. I wish I had waited until reading this before pulling the battery. Something was definitely wrong before though, hopefully I didn't break anything even more....

What will happend if you disconnect the battery terminal from battery while engine is running? Answer it will keep running,if it won't it would be good to check your altinator in fact that is how i check mine if i find i have a low battery Answer it should keep running if it won't you might want to check your altinator Answer It might, but it's very likely to fry the alternator. Alternators depend on battery impedance for current regulation. Disconnecting the battery with the engine running is just begging for a hefty repair bill. Answer Yes it will , except some early model VWs as I found out, disconnecting the battery breaks the circut A early VW will stop running , cira 1960... Answer The battery provides voltage regulation. Without it, the bus voltage in your vehicle may exceed the working voltage of many electronics in your vehicle. Cars today have many digital electronics that are susceptible to voltage spikes and are often not well equipped to handle them. You could easily destroy the engine computer or your expensive music system for example. Read more: http://wiki.answers.com/Q/Will_your_...#ixzz1Gur4YArK Read more: http://wiki.answers.com/Q/What_will_...#ixzz1GuqMDGHr

So I gave the car to my indy today, and he confirmed it was the alternator. We're getting it shipped to arrive tomorow, so hopefully all should be well by then. I wanted to diy this, but I don't think I could have had the alternator here that fast for a 25 buck shipping fee. I think I'll let him take care of this one.

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NO...! Danger, DANGER, DANGER...!! Disconnecting the battery with the engine running will result in a working alternator voltage going into ORBIT, maybe as much as 30-40 volts after most of the electrical loads are "removed", all the electronic components have BLOWN...

Just to add to this, that is reinforce that no one should disconnect his Porsche's battery while the engine is running is the factory manual (at least the 996 Turbo manual) cautions against disconnecting the battery when the engine is running. As in: "� Never disconnect battery with engine running!". Sincerely, Macster.

Ok guys, my indie wants 600 for the job(parts + labor), rushed shipping on the alternator adding $30. He's going to clear my airbag warning light as well, since I installed racing seats. He's quoting me 3 hours of labor for the alternator + airbag warning. Now the thing is, I called sunset porsche following a lead on another thread. The guy on there got the alternator for around 300 it seems. Sunset said $775 for the cheaper model, over 1k for the more expensive one!!! I thought I could have done the job cheaper diy, but where the hell are they getting those prices from? I thought sunset was considered a good source for parts? At those rates, my indie looks like a steal.

Autozone list the part cheaper then $300 last time I check and had a lifetime warranty. You could get yours rebuilt for under $100 I bet. As long as you don't tell them it came out of a porsche. Link to basic rebuild.

The regular OEM is 95 amps. a cheaper one may only be 70 amps.

Just got off the phone with my indy. He pretty much refused to put anything else in, claiming that anything other than Bosch would be highly prone to failure. I think I'll just stomach the expense in favor of peace of mind.

Oops. Disconnecting the battery with the engine on is a baaad idea- particularly with the sensitive electronics on these cars. I sure hope that nothing else got fried. You may have dodged a big bullet here. Keep us posted on the results. This kinda reminds me of when I was in High School working on my newly- rebuilt 69 Z-28 302 and was starting it for the first time. Since it wouldn't start after cranking for a while, my buddy recommended pouring fuel directly into the carburetor to "prime it." "It's safe," he assured me. Needless to say, at 17, who was I to argue? It cost me a hood repaint and a whole lotta pride... I was lucky it didn't cost me a trip to the ER. Pouring fuel into directly into a large carburetor- PAINFUL Telling the story 25 years later- PRICELESS! LOL Sorry for your misfortune- I'm sure that it will come out fine. Best regards, Tom

Hi guys, Just wanted to post back. My indy replaced the alternator and checked all of the electrical/electronic systems on the car. Everything checks out. The driving voltage is now just under 14 volts...higher than it has been for awhile. I think the old alternator had been on its way out for some time. Luckily it looks I did in fact dodge a bullet pulling the battery from the running engine. My mechanic couldn't find anything wrong other than the alternator. Thanks for the help everyone.

I don't know what it is with Porsches and the battery. I bought a 2004 Anniversary Edition, and it barely cranked over when I bought it. This was my first experience with a Porsche, so I didn't know if the way it was turning over was normal. Turned out it was not normal - they gave me a brand new (OEM I think - it was made in Germany - I forget the name that was on it). We get to this late fall and start to enter Winter - I hurt my foot and could not drive the car for about 6-8 weeks. The battery was dead. I had to jump start it, and then it was OK. We then got a big snow storm, and I don't drive around in the Winter when the ground is wet or there is still snow out, so it was in storage again for about a month. Battery was dead again. Jump started it 2 weeks ago, and it has been fine since with drives 2-4 times a week now. Other cars don't do this (even with alarms) - like my G37 - when I stored that for 2 months it started right up like nothing. What is it with Porsches? I wish I had electricity in my storage garage - I would get a battery tender. Porsches are probably the main item that keeps the battery tender people in business!