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Cayman 718 GPF Failure

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?
 
Hi Guys&Girls

Just got this information from one of our friends on the 718 forum.

He has found and purchased a reasonable priced diagnostic tool that can read your oil ash % levels.

Enclose his detailed post for your attention.

I received a £70 ThinkDIag OBD2 scanner yesterday and can confirm that this device will show the GPF ash load etc data on a 718. Device was tested on a MY2022 base 718 2L Cayman.

The menu system on this reader is somewhat obscure. The route to read the GPF data is as follows:

Connect to the ThinkDiag dongle and select 'All Systems Diagnostic'. Let the app connect to the dongle, search for the VIN, confirm the car make/model etc and then:

System Selection
DME (Engine Electronics)
Read Data Stream
K_Catalytic converter
check boxes for the following:
K210_Particulate filter, bank 1 - loading level
K211_Particulate filter, bank 1 - soot load calculated
K221_Particulate filter, bank 1 - soot load measured
K230_Particulate filter, bank 1 - oil ash load calculated
K231_Particulate filter, bank 1 - oil ash load measured

This will return readings for the above. You can then save the readings in a pdf report within the ThinkDiag app.

I had a quick look around the menus to see if this value could be reset via the ThinkDiag. I couldn't see any obvious route to this; however I did note that in the 'Special Functions' section of the DME module there is a menu option to initiate a GPF re-generation. I didnt try this.

At least this way owners can monitor their own K231 ash load values over time rather than having to rely on OPCs to (maybe) give them the data, and at cost.

Thanks again to our friend on the 718 forum

Regards
Dave
 
Hi its me again,

My 718 forum friend has sent some more information regarding this diagnostic tool

ThinkDiag dongle & app are fairly well known in the car world - they're the cheapest way to get a fully bidirectional OBD2 reader and writer that can do many different makes & models. Most people buy them to change factory settings like Start/Stop functionality; this particular one also has fairly extensive data reading / reporting abilities too.

The dongle comes with a 1 year licence for your car manufacturer of choice, chosen at setup time; other manufacturers & periods beyond a year are purchaseable via the app for a few £10s each.

I found one on Amazon and he confirmed it's the same as the one he purchased, enclose snapshot.

Dave
 

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Hi Guys & Girls

Without prejudice

Just a quick update on what we are trying to do today.

And also a re visit to a case I worked on last year.

I have been working with an owner of a 718 2019 for the past month, trying to reverse a Dealer decision to charge the owner 9K to replace a GPF filter the car doesn't need.

We have asked for an additional back pressure check, to confirm the GPF is indeed blocked.

Unfortunately after a month of trying to get this check done we are no further forward.

It seems that the information that Porsche Readings Technical department have at the moment, regarding the fitment of these expensive GPF filters and it not fixing the fault, has not been communicated to their Network.

Surely this miss diagnosis needs to stop, it's upsetting to our owners, it's embarrassing for our dealers, and it should not be happening.

However we did had some good news on Monday for one of our owners, we managed yet again to reverse a decision to charge the owner 9K to fit a new filter, based on the low differential pressure sensor reading present on a supposedly blocked filter.

Going back to Porsche Reading last year I spent 5 months trying to convince them that the low differential pressure sensor reading, contradicted the oil ash % level 100%, and the need to fit a new filter.

Back then the invoice to the customer was over 9K.

We finally convinced them to look again at the GPF report page 42.

After the repair was completed, Porsche Customer Care wrote to the customer and apologised and explained the following.

Whilst Porsche are unaware of an inherent fault with the GPFs on our vehicles.
The fault code which was present durring the investigation on your vehicle did allow the Centre and our Technical and Warranty teams to identify the fault you had experienced to be that of a Manufacturing Defect.

Well it's a shame that Oliver Hayward the Porsche guy who wrote the internal memo in March confirming that all vehicles with a production date later than December 2019 should already had the modified OPF filter fitted, was not consulted.

Because Porsche have known about this issue for a long time.

So what we need to do, is to stop trying to charge our owners for fitting GPF filters that are not at the moment, fixing this problem.

This needs to communicated out to all the Dealers.

We need to concentrate on the Algorithm / software issue, because we have proven that on all these cars that have had new filters fitted, they are all coming back with the same oil ash % nonsense.

We only have to look at Paul's experience to understand after everything that's been thrown at this fault, the car is still not fixed, and still in the garage.

Going back to our 718 owner with our requests to re check the back pressure, he has told his Service Manager today that I will act on his behalf in trying to reverse the decision to charge him for a filter he doesn't need.

Hopefully he will do the decent thing and ring me.

We have always tried to work with the Porsche Dealers to get this issue sorted, it's just a shame they don't want to work with us.

Sorry to go on, but its about time this fault was fixed.

I have enclosed a copy of a typical GPF report, page 42, for you to see what we see.

The differential pressure sensor reading is K251, and the oil ash measured load % is K231 this puts your light on and causes all this trouble.

By the way, we are now on 59K views, lets hit 60K before the month end.

Dave
 

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Hi Paul

Without prejudice

Great news, 60K views and counting.

Well, some more good news, just had some feedback from one of our members, he's just purchased the Thinkdiag diagnostic tester I mentioned on a previous post.

He's delighted with the information it provides, it shows all the information he needs to check his oil ash % level, soot readings, and the differential pressure sensor information.

Enclose below the information provided by this diagnostic tool.

One question we are always asking is when these filters show a significant measured oil ash % level, anywhere under 100 %, why doesn't this trigger the soot warning light and message to inform the driver to regenerate the filter, as written in the drivers handbook.

The soot warning light and message is controlled by the differential pressure sensor monitoring a soot pressure build up in the GPF filter.

Yet it seems that our Porsche GPF filters with 100% oil ash load measured, have no pressure at all.

Even the modified filter 982 254 400AF doesn't have any pressure when its supposedly blocked with OIL / ASH.

This may explain why the Dealers don't measure for back pressure because of these 3 reasons not to.

1. A separate back pressure check is not part of their guided fault testing when the DTC code P242F is present.

2. A back pressure check is not mentioned in the latest internal repair instructions, that was sent to the dealers on the 3rd of March this year.

3. They also believe that the very low differential pressure sensor reading is always correct on these cars, when they show oil ash at 100%, so why bother.

So it brings us once again to this question.

Why when, they try to reset the oil ash level % to zero, do they sometimes after do more than one regeneration, which uses lots of fuel and the car usually has to have several long road tests to carry out this re set.

If they are successful and get it to zero %, why when then the car is driven further or the following day does it go back up.

If the Oil Ash figure was indeed real, it can't disappear and then come back, by using a soot regeneration method, can it.

It must be some kind of magic, it can sometimes disappear and come back on the original GPF fitted.

And then reappear back in the new modified filter thats just been fitted.

WOW, THATS MAGIC, BUT NOT GOOD MAGIC.

Let's not forget, the soot warning message has never been seen on these faulty cars, if it did come on, the message on the dashboard is different and so is the DTC code.

The only thing that can influence this silliness is SOFTWARE.

I have lots more information coming in on this subject, so please keep viewing this forum to stay up-to-date.

Regards

Dave
 

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Hi its me again

Without prejudice

I've just started watching the drama on BBC 1, Death Valley, on Sunday nights.

Its about a retired actor played by Timothy Spall who's character John Chapel is a fictional detective solves case's

Wonder if we could get him to have
a look at our Oil Ash problem, afterall, one minute its there, the next its gone, and blow me, it then comes back on a new filter fitted to the car, and sometimes several filters.

We all like a mystery, but this is getting out of hand.

We have tried lots of times to engage with Porsche Technical, to try and help them get on top of this problem, sadly they will not even speak to our Club, never mind us.

A question I would really like to ask them, is when they started seeing our P242F issues in 2019, and decided to have the filter modified, did they carry out back pressure tests.

Obviously this repair would have been covered under the manufacturer's Warranty at the time.

It's well documented that Porsche changed the oil specification on the 718 GPF cars according to a Google search below.

The Porsche 718 Cayman oil specification changed as a result of the introduction of gasoline particulate filters (GPF) and the adoption of new emission standards in Europe, which occurred in September 2018. This change coincided with the introduction of the Worldwide Harmonized Light Vehicles Test Procedure (WLTP) measurement cycles.

When we started out with this issue, two years ago, the use of the wrong engine oil, was the main reason why Porsche would not cover this expensive repair.

I have heard from several Dealers where they had supposedly put in the wrong engine oil durring service, and they where made to cover the cost of a replacement GPF filter, that we now know may not have been faulty.

It's no wonder that the dealers have gone along with this ridiculous notion, that the wrong engine oil would have caused this issue.

Without confirming back pressure is present, on a suspected blocked exhaust, you run the risk of a major miss diagnosis and replacing a perfectly functioning part.

So here we are a few years on, and Dealers are still blaming the engine oil, and saying that as caused the issue.

Maybe the fact that 90% of ASH deposits in a GPF filter comes from burnt engine oil, could have also clouded their diagnosis.

But lets remember Porsche Technical have been involved with this fault since day one.

They have been more than happy to let the Dealers try and convince their customers that there is no issue with the filters, it was either the wrong oil, or driving style, which they think they can prove, by looking at data on the Val report.

We have come along way, we just need the Technical experts to own up to this miss diagnosis, and sort this issue out.

To many of these cars have been sold, sent to auction, had the GPFs removed, customers dreams shattered, its got to stop.

I apologise if I keep repeating myself on this subject, but its the only way we can keep the pressure on the manufacturer to do something.

Regards

Dave
 
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 ???????
Well another week has gone by and still no news from the Brand on how,if, when they are likely to fix my car.
The way this is going it looks like I am heading for another summer of owning a convertible sport car that I am unable to use it as it’s parked up at an OPC.

It does appear as if we have been abandoned/ignored by the club and the Brand..

Again like Dave has said - not wanting to repeat myself, please at least take this piece of advice..
If you have a post 2019 petrol car next time you have your service completed by the OPC insist on them providing your GPF val readings.. given this is supposed to be a service item they shouldn’t deny you this information.
 
Hello Paul.

I would strongly suggest going to the motoring press in your situation. I had an issue many years ago when I had a BMW Mini. I've mentioned it before in this thread but in short, Auto Express called BMW for they view on the matter and within weeks engineers from BMW AG were at my local dealership to examine the car and offer a solution to the issue. Needless to say within 2 weeks I had my car back and running perfectly.

Unfortunately sometimes we need to take matters to the next level and if it means exposing the brand we love to it's flaws then that's what we must do.

In your case, I would most definitely be seeking some form of compensation for the money you are paying for a car you aren't driving. Those who are privileged enough to own cars with centre locks due to an issue were handsomely compensated so why not those affected by this problem?

I wish you the best of luck.

Dan
 
Hi Guys & Girls

Without prejudice

Found this info on a Google search this morning, see below.

We are not suggesting that any of the vehicles we have seen have faulty tailpipe emissions in any way.

On the contrary when you look at the tailpipes they all have had no soot present, and have a light grey deposit.

Which clearly shows the GPF is functioning correctly, in dealing with the soot emissions.

Its only the function of the soot regeneration warning light and warning message, and the oil ash % measured values that doesnt make any sense at all.

We have collected data from over 30 vehicles that we have been involved with, over the last 2 years that have been diagnosed by Dealers and the owners have been told they need new GPF filters.

When we asked for the GPF page 42 diagnostic information on every car, we looked at, it showed on every car that the differential pressure sensor readings were far to low to support the dealer diagnosis of a blocked filter.

Also the calculated oil ash % value K230, always has a 0.00% value which seems questionable.

We recently discovered that these filters were modified by Porsche, and fitted on vehicles after December 2019, the first year of production.

After these new modified GPF filters have been fitted, we have seen high oil / Ash % values come straight back, and the dealers are struggling to re set the new filters to a 0.00% base line.

Which proves beyond any doubt that these filters are not the cause of this fault.

We have recently changed the oil / Ash parameters in the software on one of our vehicles, which suggests its definitely a Software issue.

This vehicle had covered 54K miles, it had an oil ash % of 100%, has had no parts fitted to it, and we are monitoring month by month.

We are still waiting for some more data to come in from the vehicles that are out there with new filters fitted, to get more information regarding this issue.

When we have collected enough data on these faulty vehicles we can then see if this constitutes to a possible GPF control defect, and then possibly take the necessary action.

Dave
 

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