First car to let me down ...
#16
Rennlist Member
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Hi all,
I have been driving for 35 years and have had/driven many cars. I have never had or heard of a car that requires "battery maintainer". How come Porsche requires this??? If it was Hyundai requiring regular battery maintainer/charger, everyone would be making fun of it. I don't get why Porsche????
I just sold my 8 year of BMW e93 with 80k miles with the original battery. I never had any battery related issue although the car set in my driveway more than 2 months at a time in freezing cold winter.
I have been driving for 35 years and have had/driven many cars. I have never had or heard of a car that requires "battery maintainer". How come Porsche requires this??? If it was Hyundai requiring regular battery maintainer/charger, everyone would be making fun of it. I don't get why Porsche????
I just sold my 8 year of BMW e93 with 80k miles with the original battery. I never had any battery related issue although the car set in my driveway more than 2 months at a time in freezing cold winter.
As far as your E93 battery lasting 8 years with no maintainer, my experience is that batteries are very inconsistent. I know someone who had the original battery in his seldom used Benz for over 7 years with no maintainer, and after it finally went, he replaced it with another factory battery that failed within the first 2 years. Go figure
Like Lex, I use my maintainer pretty regularly, especially once the weather starts to cool off. I don't see a downside.
#17
Burning Brakes
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Besides parasitic draw, which is definitely an issue with any newer car, there's the problem of self-discharge. Lead acid cells lose about 4% of their charge per week in warm weather, even if there's absolutely no draw. Which is much worse than it sounds, because 75%-80% of full charge is low enough that you'll have trouble starting.
When I retired and my "daily drive" became more of weekly drive, I ran into this problem. I just wasn't driving my car enough to keep the battery charged. And this was a '97 Toyota Supra Turbo, which was neither modern nor a Porsche.
I had a conversation with a Porsche sales guy a couple of years ago on the subject, and he mentioned that they make sure to put every car on a battery maintainer at least once a month. Because the cars on the lot aren't necessarily being driven.
When I first got my 2014 911 4S, it took about 48 hours before the Battery Tender said it was up to full charge. Which is unusually long. If that sounds like a long time to you, it's because the Battery Tender's a low current device (1.25 amps), not a rapid charger.
When I retired and my "daily drive" became more of weekly drive, I ran into this problem. I just wasn't driving my car enough to keep the battery charged. And this was a '97 Toyota Supra Turbo, which was neither modern nor a Porsche.
I had a conversation with a Porsche sales guy a couple of years ago on the subject, and he mentioned that they make sure to put every car on a battery maintainer at least once a month. Because the cars on the lot aren't necessarily being driven.
When I first got my 2014 911 4S, it took about 48 hours before the Battery Tender said it was up to full charge. Which is unusually long. If that sounds like a long time to you, it's because the Battery Tender's a low current device (1.25 amps), not a rapid charger.
#18
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My '66 Mercury Cyclone has a total of 8 fuses in the fuse box. In the old days, the battery really only started the car. Imagine the wiring for a new 911! Now, the battery does so much more... even while the car is dormant... that battery chargers are becoming a reality for cars with lots of features and extended rests.
#20
Rennlist Member
#21
#22
Rennlist Member
#23
#24
Burning Brakes
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It's worth noting that lithium-ion has a very low self-discharge rate. Self discharge is a matter of battery chemistry, and Li-Ion will last a long time without draw. However, the Tesla Model S has quite significant vampiric draw, which has long been a source of discussion among Tesla owners. Officially it's supposed to be 1% per day, but owners have self reported drains in the 2%-3% / day range, depending on things like ambient temperature.
#25
Instructor
Thread Starter
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To come back to this one, the VTS had failed - causing the electronics to go nuts, so they said. Unit replaced, car tested for a week, and handed over to me this morning.
It failed again on me at the first petrol station. Porsche techs came out, no log entries, nothing to indicate a fault. Battery showed full as well. Additional problem was that the car was stuck next to a pump, and when there is any type of issue - the hand brake is automatically applied so the car could not be moved.
The petrol forecourt would not allow a jump start next to the pumps so the techs put a new battery instead to get it started.
Back to the dealer again now.
It failed again on me at the first petrol station. Porsche techs came out, no log entries, nothing to indicate a fault. Battery showed full as well. Additional problem was that the car was stuck next to a pump, and when there is any type of issue - the hand brake is automatically applied so the car could not be moved.
The petrol forecourt would not allow a jump start next to the pumps so the techs put a new battery instead to get it started.
Back to the dealer again now.
#26
Nordschleife Master
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To come back to this one, the VTS had failed - causing the electronics to go nuts, so they said. Unit replaced, car tested for a week, and handed over to me this morning.
It failed again on me at the first petrol station. Porsche techs came out, no log entries, nothing to indicate a fault. Battery showed full as well. Additional problem was that the car was stuck next to a pump, and when there is any type of issue - the hand brake is automatically applied so the car could not be moved.
The petrol forecourt would not allow a jump start next to the pumps so the techs put a new battery instead to get it started.
Back to the dealer again now.
It failed again on me at the first petrol station. Porsche techs came out, no log entries, nothing to indicate a fault. Battery showed full as well. Additional problem was that the car was stuck next to a pump, and when there is any type of issue - the hand brake is automatically applied so the car could not be moved.
The petrol forecourt would not allow a jump start next to the pumps so the techs put a new battery instead to get it started.
Back to the dealer again now.
Jeez, sorry to hear. Did you buy car new or used? Keep us posted.
#27
Instructor
Thread Starter
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I bought new - they are replacing the battery now, I am picking it up later today.
Problem with diagnostics is that it shows different results each time, first the VTS showed failing and the battery fine, now the battery is showing as failing (which makes sense as a jump start worked the first time, and a spare battery attached worked the second time).
Problem with diagnostics is that it shows different results each time, first the VTS showed failing and the battery fine, now the battery is showing as failing (which makes sense as a jump start worked the first time, and a spare battery attached worked the second time).