What is the current state of the 'engine stumble' issue?
#76
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This is exactly why it's so frustrating for us.
1) We're under warranty so we're "supposed" to take it to the dealer.
2) Dealer doesn't see any fault codes and declares it normal.
3) We get mad at the dealer, but really it's a PCNA problem because the dealer won't be compensated for exploratory work without codes.
1) We're under warranty so we're "supposed" to take it to the dealer.
2) Dealer doesn't see any fault codes and declares it normal.
3) We get mad at the dealer, but really it's a PCNA problem because the dealer won't be compensated for exploratory work without codes.
#78
Race Director
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Originally Posted by Zonian
Interesting article here re Porsche software to limit exhaust noise allegedly causing stumble:
http://www.dailymail.co.uk/news/arti...ty-report.html
http://www.dailymail.co.uk/news/arti...ty-report.html
"Another Porsche owner called Nick Ray suffered the same problem but was allegedly told by a dealer that it was a common characteristic of the car type and there was no fix."
^^^ sound familiar??
#79
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Interesting article here re Porsche software to limit exhaust noise allegedly causing stumble:
http://www.dailymail.co.uk/news/arti...ty-report.html
http://www.dailymail.co.uk/news/arti...ty-report.html
#80
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Wow - Whatever shred of credibility this company had left regarding honesty, just flew out the window.
Their compulsion to blatantly lie at every turn clearly dates back several years and apparently knows no bounds. Not even when it relates to road safety
The news article is shocking at best and once again confirms what many of us have suspected for a very long time.
Their compulsion to blatantly lie at every turn clearly dates back several years and apparently knows no bounds. Not even when it relates to road safety
The news article is shocking at best and once again confirms what many of us have suspected for a very long time.
#81
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Wow - Whatever shred of credibility this company had left regarding honesty, just flew out the window.
Their compulsion to blatantly lie at every turn clearly dates back several years and apparently knows no bounds. Not even when it relates to road safety
The news article is shocking at best and once again confirms what many of us have suspected for a very long time.
Their compulsion to blatantly lie at every turn clearly dates back several years and apparently knows no bounds. Not even when it relates to road safety
The news article is shocking at best and once again confirms what many of us have suspected for a very long time.
#82
Nordschleife Master
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The more I'm reading on this issue the more I tend to agree that this drivability issue can be corrected through a software update from Porsche. My only concern at this point is why does it only manifest on certain cars and not across the board... Very puzzling!
#83
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If that article is accurate, it would seem that Porsche can't offer a software solution without putting the car in violation of European noise standards. So basically, Porsche knowingly used a software trick to meet sound regs at the expense of drivability and they're telling owners that doing such a thing is perfectly normal and acceptable. Kinda sucks, but I don't think they're alone in this, though I'd bet that most of the lag issues people experience on other cars has more to do with automatic transmission software programming done for fuel economy reasons.
#84
Rennlist Member
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re-flashes and this does not rectify the problem, so I dont think that's the
root cause, but its the ECU learning that is manifesting the side effect
ECU (in)directly monitors and can manipulate
I would start to correlate production dates for the cars experiencing these problems in case there is a batch of common components installed in those
cars that is out of spec and thus causing the ECU to mis-learn ... or perhaps
the ECU itself.
I might also try an aftermarket flash such as GIAC or EVOMsit etc to see if any changes to the maps would eradicate the symptoms (but I doubt that
is very likely)
#85
Rennlist Member
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another thought; what about trying a SprintBooster? Since these fool the ECU into thinking the accelerator is being pressed faster/harder it might "lessen" the duration of the stumble?
#86
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We also polled the affected car owners about their production dates to determine if there was a correlation to a bad batch.
Nothing at all with dates being all over the place.
A user installed the Sprintbooster for a while, and that only gave the sensation of being in Sport+ all the time. Didn't alleviate the stumble.
IMHO, the fact that this also happens when using cruise control eliminates the pedal / potentiometer theory.
#87
Track Day
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Interesting article here re Porsche software to limit exhaust noise allegedly causing stumble:
http://www.dailymail.co.uk/news/arti...ty-report.html
http://www.dailymail.co.uk/news/arti...ty-report.html
https://rennlist.com/forums/996-turb...ty-report.html
Here is the appeal discussed in that article:
http://www.informationtribunal.gov.u...(04.08.15).pdf
Here is the ruling for that appeal:
https://ico.org.uk/media/action-weve...s_50527543.pdf
Here is a Piston Heads thread regarding the issue; note comment 3 on that page by Chris944 which nicely summarizes the appeal document.
http://www.pistonheads.com/GASSING/t...071.01626&nmt=
#88
Rennlist Member
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I'm so sorry to hear this issue is still prevalent. I decided a year ago in September/October '14 to take the $30,000ish loss on my X51 C2S and get my GT3. I know how frustrating this is to have no one a Porsche listen to you and simply think you are crazy. Good luck all.
#89
Rennlist Member
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I've been reading about this here and on other sites for over a year. I "think" I had a very slight stumble on our 2012.5 launch 991s, but I've made a point of driving the 2014 C4s in the suspect rpm range at both "cold" and "warm" motor temps and this car has zero stumble or hesitation. So I'm as confused as anyone. Two cars, same drivetrain (PDK, sport chrono, etc), same drive modes (normal, sport, "manual" shift) with noticeably different drivetrain response characteristics that as far as I can tell should have no relationship to 2s vs 4s.
#90
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Interesting article here re Porsche software to limit exhaust noise allegedly causing stumble:
http://www.dailymail.co.uk/news/arti...ty-report.html
http://www.dailymail.co.uk/news/arti...ty-report.html