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Cayman 718 GPF Failure

Excellent Dave, it seems so simple to check back pressure, so why do they constantly refuse to check it? Maybe because the results will show how incompetent they have been throughout this whole process!
Regards
Mark
 
Hi Mark,

Without prejudice

Yes I agree, I think they have allowed this problem to get out of hand, fitting expensive exhaust parts that we said didn't need removing based on the differential pressure sensor readings.

And to confirm this, look at all our cars that have had these modified filters fitted, that have gone back to the dealers with the same fault on the oil ash % reading, after only a small mileage covered.

I recived last night this post from an owner with a 718, on the 718 Forum regarding our campaign to try and fix these cars.

Thank you for the latest update Dave. I've been following this thread (and the one on PCGB) since the start. I'm disappointed, but not entirely surprised at the resistance of Porsche to engage properly, accept the evidence you've painstakingly pulled together, and do the right thing.

I'm very grateful for your determination and persistence. As the owner of an early 2019 BGTS, I'm hoping there is a solution before I encounter the problem. I'd be happier if I knew that an ODB2 diagnostic tool like Thinkdiag, for example, could read the ash levels & initiate a GPF reset, to avoid the need to fight my local Porsche dealer in Reading, who have been less then helpful with other issues in the past. In the meantime, I'm keeping my fingers crossed and awaiting further updates from those that are already in the battle. 🤞

This was my reply back to him.

What we need to do is get our owners with GPF cars to make an appointment with their dealers and ask them to check the GPF data on their cars to make sure the GPF system is functioning correctly in view of all the trouble we have been having.

This simple check would hopefully show us it's only model year 2019 that's affected, and if this was proven to be the case, we could then look at what's different on the later cars, this may help Porsche fix this issue quicker.

The GPF report page 42 shows all the information we need and shows the oil ash measured value, that's causing all the trouble.

Afterall the Porsche Dealers classed these filters as a Service consumable to get out of replacing them through the extended warranty.

We know that the GPF is now written in as an excluded part in the new Warranty policies, it wasn't before, so it should have been covered.

So if they say the GPF filter is the same as all filters, then they have to except that the GPF filter needs to be checked periodically has a service item.

It's important that these emmision devices on all motor vehicles are checked to make sure they are doing the job they were designed to do.

Iam sure Porsche Reading would be only to pleased to help us with our investigations.

Regarding the Thinkdiag we need someone with one to try it on one of our cars.

Kind regards
Dave
 
Hi its me again,

Without prejudice

I would like to personally thank all the people that are viewing our 718 GPF Forum, over the last few posts we have picked up a further 1000 views, we are at 55K has of today.

We really need your support on this and this confirms you are with us.

IF WE COULD TURN THESE VIEWS INTO DEALER VISITS FOR A GPF OIL / ASH CONDICTION CHECK IT WOULD BE GREAT.

Once again, thankyou all for your support

Dave
 

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David, thank you for all the work you continue to do on this subject. It is incredible, that after all these posts, the information that we now have and the detailed article on page 74 of the March Porsche Post, that we still have had no response from Porsche. I have just made an appeal in the general section of this site.

This is an attempt to reach a wider audience and gain some additional weight from other owners.

We must see this through to the end.
 
Well done for opening the discussion to a wider forum audience John. On the face of it, based upon Dave’s comments, this truly is a shameful and disgraceful stonewalling operation by Porsche UK and the higher echelons of the company.

Incidentally, the PP piece mentions Martin Werner as the lead Porsche engineer for the GPF programme. A pipe-dream of course, but wouldn’t it be great if Dave was able to liaise with him directly?🤔

Hopefully perseverance will win the day … eventually! Keep up the excellent work Dave.

Jeff
 
Thanks John and Jeff for your kind words,

Without prejudice

We are not going to let Porsche abandon our 718 owners, we are not going to let these cars down. These cars are the first step to the Porsche experience, so they need to be right.

The lack of a possible software update should not spoil this experience.

We have done the hardware, GPF filters, we have changed the differential pressure sensors, we have even pulled 2 of our engines apart looking for possible oil consumption to confirm ASH buildup, we didnt find anything, we have even changed a DME.

There is no back pressure present when P242F presents itself, so what's left to check.

We know we can make changes in the software to stop our oil ash warning light coming on prematurely, so what is the problem.

The more we delay in fixing this, the more Porsche owners are not only loosing confidence in their dealers, but also in the Brand.

We need Porsche Customer Care to support their dealers when this fault shows itself, and confirm to their customers that support is available before they deliver the wrong diagnosis, they do not a new GPF filter to fix this fault.

Telling their customers it's 9K to fix this fault, and when asked what's caused the problem, and the reply is you have, is totally unacceptable and has to stop.

Today I went to a Porsche event at the Harewood Hill Climb, and carried out a AOS vacuum check on a 2023 Cayman, we have done this check on several cars and found that they read around 30 to 35 inches of water (inH20), engine warm, on tickover.

We can use this information going forward, so these very important Emission devices can be checked anytime and very quickly.

I took a video showing the reading, unfortunately the file was to large to send.
If anyone needs to see the video, just contact me and I can send it on.

Dave
 
Sorry if I have missed the clarification on this anywhere, is this a cayman rather than boxster issue as that seems very strange as they have the same engines and exhausts surely??
 
Hi Jimmy p

Without prejudice

Unfortunately we have had a few Boxsters with this issue, but it's mainly Cayman, we have also had two 991.2 2019 cars as well.
One of the 991.2 cars is going back for the oil ash check shortly, after having one of its GPF filters replaced earlier this year, the car had only covered 12K.

I would encourage anyone with a 2019 petrol car to have the oil ash % level checked, it should be part of its service schedule.


Will keep you all updated as we go along.

Regards
Dave
 
David, thank you for all the work you continue to do on this subject. It is incredible, that after all these posts, the information that we now have and the detailed article on page 74 of the March Porsche Post, that we still have had no response from Porsche. I have just made an appeal in the general section of this site.

This is an attempt to reach a wider audience and gain some additional weight from other owners.

We must see this through to the end.
Hi John,

Not sure if you are aware but I posted something similar in the general section over a month ago suggesting to owners of post 2019 cars (macan,911,718) owners to ask for the GPF to be checked at there next service.
I also included a link to the cayman post as you have.

After 2 weeks I bumped it back to the top and there was no comments or low views.

I believe this is because this section can only be seen by members unfortunately were as the cayman forum can be read and seen by the general public/ non member owner who has this issue and does a google search.

Personally I believe this is where most of our views are generated from..

With your contacts at the club could the general settings be changed to allow non members to see ?

The alternative is we post on the model forums as I expect these can be seen by the general viewer..
 
Hi John,

Not sure if you are aware but I posted something similar in the general section over a month ago suggesting to owners of post 2019 cars (macan,911,718) owners to ask for the GPF to be checked at there next service.
I also included a link to the cayman post as you have.

After 2 weeks I bumped it back to the top and there was no comments or low views.

I believe this is because this section can only be seen by members unfortunately were as the cayman forum can be read and seen by the general public/ non member owner who has this issue and does a google search.

Personally I believe this is where most of our views are generated from..

With your contacts at the club could the general settings be changed to allow non members to see ?

The alternative is we post on the model forums as I expect these can be seen by the general viewer..
Posts relating to the 718 GPF issue and GPF Val testing at OPC services uploaded on both the 992 and macan forums..
 
Hi Guys & Girls

Without prejudice

Another week of frustrating phone calls and lots of WhatsApp messages to owners providing information to try and convince their Porsche Dealers that they need to confirm that the actual differential pressure sensor information present on two of our latest cars is correct.

The first car had 1.41 hPa, and the other one had .75 hPa.

These readings were both from cars that have an oil ash level of 100%, and the dealers are saying the GPF filters need replacing, and at the moment are not covered by Porsche.

After two years of dealing with this issue, the dealers are still maintaining that the GPF filters are definitely blocked with ASH and need a replacement part.

They are still refusing our requests of doing a manual back pressure check to confirm the GPF is actually blocked.

They are definitely ignoring the differential pressure sensor readings on the GPF report, that are showing no pressure at all.

Instead of contacting Porsche Technical Reading to discuss this issue, they would rather upset our owners, and asking for 9K to supposedly fix the issue. They then embarrass themselves by not being able to answer the question, why is this fault happening, and if they are pushed for more detailed information, GPF reports etc, they finally start to get things moving with Customer Care, Technical, and the Warranty Departments.

And usually a courtesy car is not always available to any customer who dares to challenge the dealer or Porsche.

Ash build up in the GPF directly affects fuel consumption through two pathways: (1) increased exhaust flow restriction and backpressure, and (2) increased regeneration frequency, through a reduction in filter soot storage capacity.

Furthermore, the ash may also reduce the regeneration efficiency in catalyzed systems, requiring an increased reliance on active regeneration or higher temperature operation for successful passive soot oxidation.

Now if you remember I have asked every owner with this P242F oil ash load exceeded fault code, have you ever seen a soot regeneration message on your car.

Never has always been the answer, surely out of all these 6 year old cars somebody should have seen this soot regeneration light come up on the dashboard.

Unless there has always been a fault right from the start, bearing in mind we have written confirmation from Porsche admitting that modified GPF filters part no 982 254 400AF were introduced in production on December 2019 cars onwards.

We do know that if you see a soot readings of around 50% to 60% in both the Measured and Calculated data, the soot regeneration message will appear on the dashboard.

This only happened on a Cayman that had a GPF clean with a cleaner that completely contaminated the filter and put on the soot warning light and message.

We have photos and 2 fault codes to back this up.

So to sum up, Porsche are still saying these Exhausts are blocked, and they need replacing, yet if they are blocked, why isn't the soot warning light coming on, it should be, as the space in the filter is decreasing fast, so more active regenerations will be needed, and the back pressure should be increasing to.

And yet we have not managed in nearly 2 years, to get a Dealer to do a simple back pressure test on any of our cars

But the soot regeneration light and message, isn't coming on, these cars are running fine, we fit new filters, which make no difference at all, new differential pressure sensors, new AOS, and even engine strip downs looking for internal oil consumption to substantiate excessive oil ash build up.

Even a new DME has been fitted, in a bid to re set the oil ash % level in our cars, and that failed to fix the fault.

It should be really easy to reset the soot and the oil ash levels to zero once a new GPF has been fitted.

WHY CAN'T THIS SIMPLE TASK BE DONE

An algorithm is used to measure ash content in a GPF Filter and it typically relies on a combination of sensor data, historical performance, and predictive models to estimate ash accumulation. This process doesn't directly "measure" ash in the sense of a lab experiment, but rather uses indirect indicators to infer its presence and quantity.

The differential pressure sensor should control the soot levels and regeneration process in our cars.

HOW LONG IS THIS GOING TO GO ON

Sorry to go on, but this is becoming a bigger issue on these cars, bearing in mind all these new parts that have been fitted, and the fault as not been fixed yet.

WHATS WRONG WITH LOOKING AT THE SOFTWARE.

I have been asked many times for information on diagnostic testers that can read the Oil Ash % levels on our cars.

Owners of these cars are obviously worried if they are going to have the same issues they have seen on our forum.

We are currently on 56 K views on this subject on our forum at the moment.

I would say to any owner of a vehicle with a petrol GPF fitted, to get their Porsche Dealer, or independent Garage to do this simple check and put their mind at rest.

Regards

Dave
 
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Hi its me again,

Sorry but we need to keep the pressure on, pardon my pun

Without prejudice

This is a question that the dealers never answer.

Why when my GPF filter is blocked with ASH and it needs replacing, have I not seen this soot warning message on my dashboard.

Afterall with pressure in my exhaust due to the blockage, this warning message should be triggered.

The pressure is monitored by the differential pressure sensor, and it does not care if it's caused by Ash or Soot, pressure is pressure.

To anybody out there who is having Gpf issues, and your Dealer is telling you, your GPF needs replacing, please ask your Dealer this question.

Enclose a photo of the soot warning message you have never seen.

Regards
Dave
 

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I follow this thread with great interest though I have a simple 987.2.
Tenacity will win, hound everyone you can who will listen.
I hope the Auto Express will pick it up.

Really not sure Porsche deserve any consideration here, the fault is clear, there lack of action clear too; must be a way through all this stone wall action,
just poor Customer Care.
They have taken the money, and to hell with the Customer.
I presume the Club have not made any progress?
 
Hi 911Hillclimber

Without prejudice

Thanks for responding so quickly,

It's such a simple question, when you think about it, we just need the answer, and they will have to give us the answer.

Will keep pushing on, I have lots more info to send out, we just need a response to this especially from Porsche Reading Technical.

It's about time they engaged with us, we are trying to save Porsche money, and the embarrassment of a serious miss diagnosis on this fault.

Keep in touch

Dave
 
Hi Guys & Girls

Last post of today, some really good news for once.

Just checked our views on our GPF campaign, we are currently at 58K views.

On the 12th of September last year we had 15K views, that's an increase of 43 thousand views over the last 8 months.

This just shows that this campaign to get our cars fixed is gaining headway, and it's all Thanks to you.

Can we hit 60K before the end of the month

Dave
 
Unfortunately Dave the only way it will gain headway is if a solution is offered by Porsche. Unfortunately views don’t provide this (I wish they did) but what they do provide is more evidence that those affected can give to their OPC. It’s sad that Porsche AG won’t step up to the plate but it does beg the question whether Porsche GB are protecting the mother ship from the issue.

Dan.
 
Hi All,

Latest update on my car
After having the 3rd GPF fitted (new not a refurb)
2 differential pressure sensors in 6 months
An engine out strip down and rebuild
Live road testing with computers monitoring

And to top that a new DME fitted as recommended by PAG..last week

20 mile road test and the GPF registered 25% full…🤦🏻‍♂️

Porsche UK Reading technicians are now finally attending the OPC this Weds.. to do what ??? I have no idea..

It’s getting very close to a stage where the people that designed and built these cars can’t fix them… fingers crossed it doesn’t get to this point .

And for the OPC’s that still quote it’s driving style, wrong oil, etc , etc..

It’s complete BS as my case is 100% proof, as all this work and testing results has taken place over the last 5 months by Porsche since my car has been back at the OPC…

Let’s see what Wednesday brings…

And finally a big thankyou to all that follow our journey..
Hi All,

Latest Update -
3 weeks ago a team from Porsche Reading turned up at my OPC to fix my car.
After spending the whole day completing various testing and resets (sorry this is the only detail I have been provided) they apparently manage to obtain a zero reading on the 3rd GPF fitted that must have completed less than 100 miles.

Car was road tested over night and a VAL report completed the following day..

48% full after completing a road test of around 40 to 50 miles …

By this time the Experts ( 🤦🏻‍♂️) from Reading had returned back to their centre of excellence(🤦🏻‍♂️).

My understanding is that following this test result a conversation between Reading and PAG took place and the OPC was asked yet again to inspect for signs of oils on the inlet manifold… (this has been completed so many times I think they have got this task down to McLaren pit stop standards)

And surprisingly no sign of oil…

At this time my car is still in bits awaiting further instructions from the brand …. Don’t hold your breath

I have yet again suggested software as the probable root cause for the umpteenth time over the last 10 months but still the brand chooses not to listen..

I have managed to obtain a couple of pictures of the 2nd GPF that was fitted last Sept that I estimate to have completed less that 1000 miles and it doesn’t appear to look evident of showing signs of being 50% full.. as the previous readings have suggested…(pictures attached)
You can make your own opinion and comment on the pictures..

As of next week my car has been with the brand for 20 weeks (since early Jan 25) after having the 2nd GPF fitted in Sept (24) last year and the guys that designed and built it still can’t fix it ???????
 

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Hello Paul.

I think you may well be the test case for this issue and I really hope it leads to a positive result for you and others. I would like to think that as a minimum PORSCHE have put you in one of their loan cars and plan on compensating you for the inconvenience you’re experiencing.

Best of luck.

Dan.
 
All clean as a whistle it seems.
Not so Porsche.
All about money here I think, a veritable flood gate has built up and this will be a key consideration but they must realise the day of judgement is soon coming and the problem has to be addressed conclusively.
Bolting things off and on is easy, fixing software will be hell in comparison.

20 weeks off the road, experts arriving and speeding away must give some grounds for full recompense via the Laws of this country?
 

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