Cayman 718 GPF Failure
- Thread starter Wrightrubber
- Start date
Hi Guys & Girls
Without prejudice
Now that we are fairly certain that the GPF filters are definitely not the issue with the cars we have been involved in.
A simple exhaust back pressure check at the differential pressure sensor connection would have confirmed this very quickly.
No need for expensive exhaust systems, and lots of customer distress.
I found this video on YouTube that shows in detail the affects of back pressure, it's on a diesel car buts it's the same on a GPF.
Our thoughts regarding the possible software fault, are that the oil ash level is increasing to quickly, and it may be preventing the soot regeneration warning light function from working correctly.
There is no regen on a GPF in the same way as there is on a DPF.
It isn't required, but when / if a partial blockage occurs the soot loading warning light should work.
Durring this procedure some tiny amounts of ash does get ejected, hence the brownish deposit on your tailpipes.
But mostly all that happens is the debris gets a good shake up with the help of the vacuum created in the exhaust durring active regeneration.
And this unclogs the filter, allowing the ash (which is mostly harmless) to settle in the collection chamber in the GPF.
They say it will take a car a lifetime to fill the GPF for most people driving these cars.
Kind regards
Dave
Without prejudice
Now that we are fairly certain that the GPF filters are definitely not the issue with the cars we have been involved in.
A simple exhaust back pressure check at the differential pressure sensor connection would have confirmed this very quickly.
No need for expensive exhaust systems, and lots of customer distress.
I found this video on YouTube that shows in detail the affects of back pressure, it's on a diesel car buts it's the same on a GPF.
Our thoughts regarding the possible software fault, are that the oil ash level is increasing to quickly, and it may be preventing the soot regeneration warning light function from working correctly.
There is no regen on a GPF in the same way as there is on a DPF.
It isn't required, but when / if a partial blockage occurs the soot loading warning light should work.
Durring this procedure some tiny amounts of ash does get ejected, hence the brownish deposit on your tailpipes.
But mostly all that happens is the debris gets a good shake up with the help of the vacuum created in the exhaust durring active regeneration.
And this unclogs the filter, allowing the ash (which is mostly harmless) to settle in the collection chamber in the GPF.
They say it will take a car a lifetime to fill the GPF for most people driving these cars.
Kind regards
Dave
Just for the record Dave, how many views has the this story had ?
I wonder if the club has the capability and know how to see how many are linked to a Porsche IP address ?
Could this information give us some insight into whether anyone within the Brand is taking this issue seriously or at least acknowledging it ?
John is this something you could pick up with the club as it doesn’t appear as if the article in this months Porsche Post has rattled any cages in Reading.
Last edited:
Greenman986S
PCGB Member
this thread has had 41000 views to date....
Hi Guys & Girls
Without prejudice
Struggling to find any GPF information on YouTube that talks about the calculations that are needed for the regeneration of soot.
This video covers what happens regarding DPF regeneration, but we can apply this to a GPF system.
Three quarters into the video, it explains the factors concerning regeneration and it mentions exhaust back pressure.
Sorry for mentioning back pressure, but it's been my favourite subject for the last 2 years.
Only because for some reason our Porsche dealers and Porsche Reading seem to be reluctant to carry out this simple test on our faulty cars.
We have one of our Caymans in at the moment, that will be shortly having its second GPF fitted, after the original GPF for this oil ash fault.
Sorry for repeating myself again, but the recent information we have on one of our cars from last year, clearly points to the incorrect coding of the oil / ash parameters.
Surely this coding issue could be sorted out quite quickly, and our cars put right once and for all.
Enjoy the video
Regards
Dave
Without prejudice
Struggling to find any GPF information on YouTube that talks about the calculations that are needed for the regeneration of soot.
This video covers what happens regarding DPF regeneration, but we can apply this to a GPF system.
Three quarters into the video, it explains the factors concerning regeneration and it mentions exhaust back pressure.
Sorry for mentioning back pressure, but it's been my favourite subject for the last 2 years.
Only because for some reason our Porsche dealers and Porsche Reading seem to be reluctant to carry out this simple test on our faulty cars.
We have one of our Caymans in at the moment, that will be shortly having its second GPF fitted, after the original GPF for this oil ash fault.
Sorry for repeating myself again, but the recent information we have on one of our cars from last year, clearly points to the incorrect coding of the oil / ash parameters.
Surely this coding issue could be sorted out quite quickly, and our cars put right once and for all.
Enjoy the video
Regards
Dave
Greenman986S
PCGB Member
i think the Club's privacy policy doesn't allow that
We collect data from our website for a number of reasons, primarily to provide you with the most useful and relevant information and services from Porsche Club GB. We do this through collecting and analysing both anonymous, or aggregate, data, and personal data volunteered by you online.
We have enough information to know that Porsche GB are aware of this issue but, it seems, even they have not come to a definitive conclusion as to the cause of these readings. As Dave's work has demonstrated, there are so many contributory factors. Porsche continue to deal with these issues on an individual basis and Dave has a number of cases ongoing, with new factors emerging every week.
We are trying to put together a follow up to the PP article but we still need Porsche's response if possible.
We are trying to put together a follow up to the PP article but we still need Porsche's response if possible.
Hi John,
Well all I can say is that Porsche need to do something PDQ to support the owners and OPCs as I am just about to have my 3rd GPF fitted and the car has done less than 14k miles.. it’s been back at the OPC for coming up to 10 weeks after the second one registered 46% in less and 800 miles and my engine has been out,stripped down and rebuilt and put back in..
I am still being told it’s not a software issue ??????
3 GPFs and an engine rebuild, which presumably didn’t throw-up any significant issues?
And Porsche still hasn’t got to the bottom of the problem! How long has your car been off the road Paul?
I’d be pushing for a new engine [including a complete exhaust system] and some hefty financial compensation for all the inconvenience.
Jeff
And Porsche still hasn’t got to the bottom of the problem! How long has your car been off the road Paul?
I’d be pushing for a new engine [including a complete exhaust system] and some hefty financial compensation for all the inconvenience.
Jeff
Hi Jeff3 GPFs and an engine rebuild, which presumably didn’t throw-up any significant issues?
And Porsche still hasn’t got to the bottom of the problem! How long has your car been off the road Paul?
I’d be pushing for a new engine [including a complete exhaust system] and some hefty financial compensation for all the inconvenience.
Jeff
Had the car just over a year and it’s spent 18 weeks at an OPC.
That’s a ridiculous amount of time Paul.
In case you’ve not seen it, you may be interested in this thread pertaining to an issue with 992 wheel centre-locks, especially if you’re using finance to purchase your car because it could be a route to claiming financial compensation through a vehicle off road:
www.porscheclubgb.com
Good luck!
Jeff
In case you’ve not seen it, you may be interested in this thread pertaining to an issue with 992 wheel centre-locks, especially if you’re using finance to purchase your car because it could be a route to claiming financial compensation through a vehicle off road:
Stop using vehicle recall on center locking 992s
How are folks handling this? I've only got the one car, so stopping use completely gets in the way. However, if the official recall says to stop using vehicle, does that mean that insurance wont be valid until its fixed?
www.porscheclubgb.com
Good luck!
Jeff
Hi Paul, I am aware of the issues you have had with your car and the teatment you have had from both the OPC and Porsche. Please correct me if I am wrong, but I understand that despite the work they have done on the car , they have still not found a solution, or even got to the bottom of the issue. Yours is unfortunately the most extreme case and if there is a way of assisting, please drop me a mail or give me a call.
Hi John,
Yes you are correct, I am currently awaiting the arrival of a new GPF as apparently the 2nd one that was fitted was an exchange part(apparently standard practice by Porsche Warranty to fit refurbished parts) and they now think this is the issue ???
Unfortunately it appears to me as if the OPCs receive little and no help from the brand with Technical issues like this and due to warranty constraints any self driven investigation work is very limited by the franchise.
Unfortunately I wouldn’t say my case is the most extreme, I would say I am further down the line than others and have been very thorough in documenting my journey along with setting and agreeing key tests after work has been completed with the OPC which has highlighted that previously just changing these hasn’t fixed the problem.. (I feel for those that either paid or contributed before Dave got hold of this)
The good news is that unlike others my OPC and its Gold Techs have been very good in supporting trying to resolve this issue.
To assist me/us if you do have any contacts or leverage within Readings HQ then I/we would appreciate you rattling their cage for a official response from the Brand, we are not going to give up on this until they have provided both a root cause and fix…
My major concern is that if it does prove to be a software fault we don’t end up in another Dieselgate saga….
I was at a regional meet last night and was speaking to one of the staff from the hosting OPC. They said that they'd had a few GPFs replaced on the 2.0 models. They didn't say whether they were done under warranty or not but they said that speaking to one of the Techs, the theory was it's down to software.
Dan
Dan
Hi Dan,
Without Prejudice
This could be good news, coming from a dealer, I had a phone call from one of our Cayman 718 drivers last night, that I have been talking to for over a year now.
He contacted me last March 2024, with the usual GPF fault and was quoted the usual 8K.
We agreed that after several checks on other vehicles showing no back pressure, he should drive the vehicle and wait to see if Porsche come up with a repair solution.
So a year on and over 10,000 miles covered, with the warning light P242F coming on and off only 3 times, and also a service at an OPC last November, the car as run great without any other issues.
No problems found with performance or economy during the 10K.
Surley with a supposedly blocked GPF filter, this could not happen, we had a dealer recently who told one of our owners that their could be a fire risk on his car if he drove 150 miles to the garage.
The car was picked up by a recovery truck to investigate the GPF 100% oil ash level exceeded.
This car is still in the workshop after having the engine removed and stripped down looking for internal oil contamination.
Nothing found that would cause an Oil / ASH buildup that would fill a filter to 100% in such a low mileage covered.
I believe the reluctance of Porsche Reading Technical Department to confirm that the car software is telling the truth, is making this situation even worse.
Why have none of the dealers concerned with this issue on our cars, not given our owners the proof that a back pressure check as been carried out, from the beginning of diagnosis.
Also what happened to our GPF filters in 2019, that made Porsche modify a GPF that had been on these cars less than 12 months.
We need answers to these questions please.
Regards
David
Without Prejudice
This could be good news, coming from a dealer, I had a phone call from one of our Cayman 718 drivers last night, that I have been talking to for over a year now.
He contacted me last March 2024, with the usual GPF fault and was quoted the usual 8K.
We agreed that after several checks on other vehicles showing no back pressure, he should drive the vehicle and wait to see if Porsche come up with a repair solution.
So a year on and over 10,000 miles covered, with the warning light P242F coming on and off only 3 times, and also a service at an OPC last November, the car as run great without any other issues.
No problems found with performance or economy during the 10K.
Surley with a supposedly blocked GPF filter, this could not happen, we had a dealer recently who told one of our owners that their could be a fire risk on his car if he drove 150 miles to the garage.
The car was picked up by a recovery truck to investigate the GPF 100% oil ash level exceeded.
This car is still in the workshop after having the engine removed and stripped down looking for internal oil contamination.
Nothing found that would cause an Oil / ASH buildup that would fill a filter to 100% in such a low mileage covered.
I believe the reluctance of Porsche Reading Technical Department to confirm that the car software is telling the truth, is making this situation even worse.
Why have none of the dealers concerned with this issue on our cars, not given our owners the proof that a back pressure check as been carried out, from the beginning of diagnosis.
Also what happened to our GPF filters in 2019, that made Porsche modify a GPF that had been on these cars less than 12 months.
We need answers to these questions please.
Regards
David
Hi Guys & Girls
Without prejudice
I would like to share this information I found recently, while helping out an owner with a 991.2 2019, with quess what a supposedly failed GPF filter.
We manged to get a copy of his GPF report which I can share with you.
Thankfully this was all we needed to persuade the dealer and Porsche to cover the repair for the bank 1 GPF filter under warranty.
If you look at the report you will see K231 bank 1 oil ash at 100%, looks familiar.
If you look at the differential pressure value K251 it's at -0.25 hpa, looks familiar.
A very low pressure reading for a supposedly blocked filter.
Now bearing in mind the bank 1 GPF is apparently blocked at 100%, so why are both soot calculated values the same at .78%.
The bank 2 oil ash level K232 is showing 58.04%, so that's on its way to, according to Porsche, this wasn't replaced under warranty.
What I don't understand is how can the exhaust gas calculated temperatures T255,T256,T251,and T252 be all the same, yet you would expect the bank 1 GPF filter to be running alot hotter with all the back pressure from the supposedly blocked filter.
If this isn't a case of the software on this car being incorrect I don't know what is.
Afterall we have enough evidence now that fitting new expensive GPF filters doesn't correct the oil ash % value, and the dealers are struggling to re set them to zero.
When is the penny going to to drop, that the software on these cars is flawed, and needs attention.
My theory, for what it's worth, is because of the fact that the soot regeneration light and message does not appear to be working on any of our cars, it could be allowing the oil ash level % to come on far to soon.
We know that in the coding of the ECU we can adjust, or remove the oil ash % warning light which clears the code.
What we need is Porsche to look into this software, and stop fitting these exhausts.
Just have a look at this 991.2 report, and any feedback would be appreciated.
Many thanks
Dave
Without prejudice
I would like to share this information I found recently, while helping out an owner with a 991.2 2019, with quess what a supposedly failed GPF filter.
We manged to get a copy of his GPF report which I can share with you.
Thankfully this was all we needed to persuade the dealer and Porsche to cover the repair for the bank 1 GPF filter under warranty.
If you look at the report you will see K231 bank 1 oil ash at 100%, looks familiar.
If you look at the differential pressure value K251 it's at -0.25 hpa, looks familiar.
A very low pressure reading for a supposedly blocked filter.
Now bearing in mind the bank 1 GPF is apparently blocked at 100%, so why are both soot calculated values the same at .78%.
The bank 2 oil ash level K232 is showing 58.04%, so that's on its way to, according to Porsche, this wasn't replaced under warranty.
What I don't understand is how can the exhaust gas calculated temperatures T255,T256,T251,and T252 be all the same, yet you would expect the bank 1 GPF filter to be running alot hotter with all the back pressure from the supposedly blocked filter.
If this isn't a case of the software on this car being incorrect I don't know what is.
Afterall we have enough evidence now that fitting new expensive GPF filters doesn't correct the oil ash % value, and the dealers are struggling to re set them to zero.
When is the penny going to to drop, that the software on these cars is flawed, and needs attention.
My theory, for what it's worth, is because of the fact that the soot regeneration light and message does not appear to be working on any of our cars, it could be allowing the oil ash level % to come on far to soon.
We know that in the coding of the ECU we can adjust, or remove the oil ash % warning light which clears the code.
What we need is Porsche to look into this software, and stop fitting these exhausts.
Just have a look at this 991.2 report, and any feedback would be appreciated.
Many thanks
Dave
Attachments
Morning Guys&Girls
Well, we are now on 43K views, we are on the home straight, with more information supporting our cause.
Have a good weekend
Dave
Well, we are now on 43K views, we are on the home straight, with more information supporting our cause.
Have a good weekend
Dave
Posts made and opinions expressed are those of the individual forum members
Use of the Forum is subject to the Terms and Conditions
