Engine Stops Running 2014 991 911 Turbo
11-19-2018 | 04:28 PM
#16
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Thanks. You know, I'm an engineer, and I would hate to have a problem like this in my product. However, I would hate even more that people would have to take hail Marys 'cause I didn't know how to fix it! Hard to believe there can't be a definitive answer.
11-19-2018 | 05:06 PM
#17
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From: Gone. On the Open Road
Intermittent problems are really tough to nail unless you’re logging (and your logging code is solid) when they occur.
Millions of lines of code in these things nowadays.
If you can figure out how to repeat it, you can take a senior tech for a drive with the PWIS in logging mode. (BTDT.)
I have also BTDT with an issue on our Macan that was ‘fixed’ by reflashing the engine ECU.
Your 2014 is ‘old’ enough that there might be some patches in the latest versions.
11-19-2018 | 05:45 PM
#18
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I am also an engineer. Software. And lots of professional experience in embedded.
Intermittent problems are really tough to nail unless you’re logging (and your logging code is solid) when they occur.
Millions of lines of code in these things nowadays.
If you can figure out how to repeat it, you can take a senior tech for a drive with the PWIS in logging mode. (BTDT.)
I have also BTDT with an issue on our Macan that was ‘fixed’ by reflashing the engine ECU.
Your 2014 is ‘old’ enough that there might be some patches in the latest versions.
11-19-2018 | 06:49 PM
#19
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Being a physicist and a SW engineer too, the only thing I can say that troubleshooting intermittent issues w/o reproducing while capturing all the debug info is art. It sometimes could be done analytically, but to do so one needs to have certain knowledge of underlying designs and as much data as possible. Porsche at proper engineering level can do it, unfortunately not at your dealership service department or even at Porsche field support..
11-20-2018 | 02:07 AM
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Being a physicist and a SW engineer too, the only thing I can say that troubleshooting intermittent issues w/o reproducing while capturing all the debug info is art. It sometimes could be done analytically, but to do so one needs to have certain knowledge of underlying designs and as much data as possible. Porsche at proper engineering level can do it, unfortunately not at your dealership service department or even at Porsche field support..
Thank goodness for the recent Copyright Office exemption that will enable hackers to break encryption, violate T&Cs, and copyright for the purposes of repair. Too much of the function of modern cars is locked away deep in code. And it's pretty damn hard to find a 'bug' by looking at the binary. (Although I once employed an engineer who was a magician at finding bugs in third party code by looking at core dumps.)
11-20-2018 | 09:43 AM
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You would be underwhelmed - I know I was - by the transparency of the inner guts at the dealership tech level. There's not even enough design knowledge to unambiguously interpret the PWIS logs. They have to be e-mailed to PCNA where, as of 2015, there were exactly three folks that could look at the logs and determine - and not without a lot of throwing parts at the car - what is 'up.'
Thank goodness for the recent Copyright Office exemption that will enable hackers to break encryption, violate T&Cs, and copyright for the purposes of repair. Too much of the function of modern cars is locked away deep in code. And it's pretty damn hard to find a 'bug' by looking at the binary. (Although I once employed an engineer who was a magician at finding bugs in third party code by looking at core dumps.)
Thank goodness for the recent Copyright Office exemption that will enable hackers to break encryption, violate T&Cs, and copyright for the purposes of repair. Too much of the function of modern cars is locked away deep in code. And it's pretty damn hard to find a 'bug' by looking at the binary. (Although I once employed an engineer who was a magician at finding bugs in third party code by looking at core dumps.)
My money is on a connector ...
11-20-2018 | 10:25 AM
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With the battery and crank position sensor replaced it could still be hardware or software.
My general grousing on the nature of diagnostic support is not specific to your issue.
Since you report that ‘they tried a reflash’ it isn’t a known software issue that’s been patched.
Yes. A poor connection is a possibility. Along with a near break in one or more wires inside a harness. Infant mortality of the CPS. Actual hardware issue with an ECU (there are a bazillion ECUs. Well, not a bazillion, but more than 5 on modern Porsches.) We could go on... but...
... there’s little point unless you can figure out which pothole you hit or witch Ley line (see what I did there) you’re driving over that triggers this.
It’s out of warranty yes? Or do you have CPO? I’m unsure of legal recourse for bugs with a non-new car.
My general grousing on the nature of diagnostic support is not specific to your issue.
My money is on a connector ...
Yes. A poor connection is a possibility. Along with a near break in one or more wires inside a harness. Infant mortality of the CPS. Actual hardware issue with an ECU (there are a bazillion ECUs. Well, not a bazillion, but more than 5 on modern Porsches.) We could go on... but...
... there’s little point unless you can figure out which pothole you hit or witch Ley line (see what I did there) you’re driving over that triggers this.
It’s out of warranty yes? Or do you have CPO? I’m unsure of legal recourse for bugs with a non-new car.
11-21-2018 | 04:09 PM
#23
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With the battery and crank position sensor replaced it could still be hardware or software.
My general grousing on the nature of diagnostic support is not specific to your issue.
Since you report that ‘they tried a reflash’ it isn’t a known software issue that’s been patched.
Yes. A poor connection is a possibility. Along with a near break in one or more wires inside a harness. Infant mortality of the CPS. Actual hardware issue with an ECU (there are a bazillion ECUs. Well, not a bazillion, but more than 5 on modern Porsches.) We could go on... but...
... there’s little point unless you can figure out which pothole you hit or witch Ley line (see what I did there) you’re driving over that triggers this.
It’s out of warranty yes? Or do you have CPO? I’m unsure of legal recourse for bugs with a non-new car.
11-22-2018 | 03:47 PM
#24
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I would first try to figure out if an eventual repair of a problem reported repeatedly before the expiration of the CPO would be covered if the repair occurs after expiration. (This is true for the original warranty. I would hope it’s true for CPO.) You’ll want to make sure that service advisors are actually documenting your complaint and that’s reflected in your paperwork.
Hope it becomes less intermittent?
As for reproducibility, as long as you can reproduce it in a not-too-lengthy test drive with a tech in the passenger seat, you can get a log.
The ‘easy’ option is to sell or trade it in.
11-27-2018 | 12:37 AM
#25
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This is a tough spot.
I would first try to figure out if an eventual repair of a problem reported repeatedly before the expiration of the CPO would be covered if the repair occurs after expiration. (This is true for the original warranty. I would hope it’s true for CPO.) You’ll want to make sure that service advisors are actually documenting your complaint and that’s reflected in your paperwork.
Hope it becomes less intermittent?
As for reproducibility, as long as you can reproduce it in a not-too-lengthy test drive with a tech in the passenger seat, you can get a log.
The ‘easy’ option is to sell or trade it in.
Not giving up that quickly. There is a cause and someone has experienced it. New DME, alternator, or wiring/connection are the front runners.
I hope to stumble upon a tech or Porsche engineer who has something from experience with the symptoms. Hard to reproduce, but you can see it in the video pretty clearly.
Maybe someone knows the original owner, they were on the West Coast of Florida, like Clearwater I think. Perhaps they have some insight?
Thanks.
Last edited by LemonDrop; 11-27-2018 at 12:41 AM. Reason: Seeking original owner.
11-27-2018 | 12:42 AM
#26
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Yachting Blue with Racing Yellow painted bits.
Pretty unique interior ... anyone know the original owner? Maybe they could offer some insight? (I added the Alcantara console lid)
Somewhere near Clearwater Florida?
12-06-2018 | 12:38 AM
#27
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Best of luck with this head-scratcher.