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Cayman 718 GPF Failure

Hi Sp1ke.

Without Prejudice

With regards to your question regarding 718 cars, all the replacement GPFs filters we have been involved in, have been 2019 cars.
Both the 2.0 and 2.5 engines, boxster or Cayman.

I have a friend with a Cayman GT4, he has never seen a soot warning light come on his dashboard.
And thankfully not had any oil ash warning lights displayed.

If you are thinking of purchasing one of these cars ask the dealer to confirm in writing that the car as a functioning soot warning light.
And in the event of the GPF requiring replacement it would be covered under warranty, either by Porsche or them.

Hopefully Porsche will sort out this issue and there will be no need for any of this.

Its becoming more clear that the GPF filters replaced on our cars over the last year, are now starting to show unacceptable high oil ash readings, over very low mileages covered.

We will be testing for exhaust back pressure on any future cars brought to our attention, to challenge the diagnosis that these GPF filters need replacing.

Porsche Technical need to look at the parameters set in the ECU, that control the emission system.

Where does the ECU get the oil ash measured value from, look at the algorithm.

Sorry to labour the point again, whey are the Dealers struggling to re set the oil ash % after the new filters have been replaced.

And why on our cars is the oil ash level increasing faster than it did before.

We will get to the bottom of this one way or the other.

Will keep intouch with any progress
Dave
 
Hi Guys & Girls,

Without Prejudice

Would just like to wish everybody a Merry Christmas and a Happy New Year.

We have lots to do in the new year, after confirmation on several of our cars that fitting a new GPF does not fix the oil ash % issue.

We have always said that the GPF readings on the Val report make no sense at all.

So this is where we are focusing are attention, will keep in touch with any updates.

Thankyou for all your support over the last year, its much appreciated.

Dave
 
Hi Dave
Merry Christmas to you too!
Thanks for all your hard work on the GPF issue, keep it up and I look forward to the progress in 2025.
Regards
Mark
 
Same here Dave, and those affected undoubtedly will be thankful for your efforts this year. Keep up the good work in 2025 … hopefully with a final resolution!

Jeff
 
Dave, thank you for all your hard work researching this issue and battling on behalf of those afftected. Best wishes for the New Year.
 
Thanks John,

Without Prejudice

Happy new year to you, and the club, looking forward to hopefully sorting out this fault on these cars, and appreciate all the help from my friends on this cause.

Dave
 
While not a current Cayman/Boxster owner I am following this thread with interest

There does seem to be a wider industry problem with these filters as well as the possible 2019 Cayman/Boxster issue with sensors

My daily is form another German mark famous for its six cylinder engines and I have a performance version that sounds like "N" followed by low value numbers

From new in Oct 2022 its had its OPF/Cat replaced at approx 8.5k miles and a required dealership regen at 21k miles - internal wooden dollars price was £8.5k for the cats to be replaced

This manufacturer also has integrated its GPF/OPF with the cats

In the first instance it could not regenerate the OPF/GPF, no warning light just a failure to hold highest gear at motorway speeds and a massive drop off in mpg

Other than the dealership doing it under warranty without too much fuss the experience is similar -

Initial push back was "wrong fuel" (I use Vmax exclusively which is the vehicles recommended fuel) ,

Then "you are running the tank too low it doesn't like that" (I almost always fill up at half a tank),

Then "your not driving it properly", I was but sometimes had to drive as a normal commuter

Advice was to get the car warm and on long journeys - Run it from stationary up to 140kmh(88 ish MPH) then use the gears in high revs to slow it down, keep repeating this and run it at speed in lower gears from time to time

I was told "its just a different way of driving" as I needed to do this as part and parcel of usual commuting/car usage - Really in the UK, with UK roads and weather, cameras and in car dash cams????

I do a couple of short and two 1hr 15 return journeys a week, so plenty of time for an effective regen without aggressive driving, if the cars software did it's job.

Like Caymans there isn't a warning light so when the problem hits its too late to resolve without intervention.

It wasn't that I didn't drive moderately enthusiastically just can't do it all the time - UK motorways for longer journeys are not the place to do silly stuff. My enthusiastic driving is with my Porsche

Likewise Policy is to blame the driver rather than say, "woops we sold it as an everyday car that is really good fun to drive quick but you need to rag it all the time".

I've seen lots of other manufacturers with similar problems, even since Diesel DPF days

Doesn't help you guys so much - But it seems to be across multiple manufacturers they've had to implement some poorly thought out legislation and don't want to get stung for the consequences.

But the general message on preserving GPF/OPF across multiple manufacturers is drive them regularly through full heat cycles and drive them hard and run them regularly in sprot and sport+ modes
 
Hi Okellyt.

Thank you for the insight. There are some interesting parallels, especially is terms of the reaction from dealers about how to drive it properly. How much 'noise' has there been from owners?

One big difference is that none of the affected Caymans have demonstrated any reduction in performance or high fuel consumption. They have all run as normal, but with a check engine light on. This is one of the contributory factors to us thinking that GPF failure is an incorrect diagnosis.. It is also interesting that your car is a late 2022. The affected Caymans are all 2019, and we believe that to be the first 9 months or so after the GPF was initially introduced. We have no evidence that 2022 Caymans are affected. This could be a matter of time, but so far there seems to be a clear cut off once into 2020. However more cases are coming through and it remains to be seen where the story will end.

Best wishes, John
 
Hi Okellyt.

Thank you for the insight. There are some interesting parallels, especially is terms of the reaction from dealers about how to drive it properly. How much 'noise' has there been from owners?

One big difference is that none of the affected Caymans have demonstrated any reduction in performance or high fuel consumption. They have all run as normal, but with a check engine light on. This is one of the contributory factors to us thinking that GPF failure is an incorrect diagnosis.. It is also interesting that your car is a late 2022. The affected Caymans are all 2019, and we believe that to be the first 9 months or so after the GPF was initially introduced. We have no evidence that 2022 Caymans are affected. This could be a matter of time, but so far there seems to be a clear cut off once into 2020. However more cases are coming through and it remains to be seen where the story will end.

Best wishes, John
John

Thanks - I think with Caymans, as others have said, it's likely a sensor issue with the 2019 cars.

But I wanted to share a wider longer term issue drivers of the other performance vehicles are seeing with GPS/OPF's actually coke-ing up and causing problems

The gear and fuel economy issue is the car constantly trying and failing to regen at speed..... So it holds a lower gear and higher revs in an attempt to fix it but it's not enough

Drive it round town and you see nothing to tell you there is a problem, no warning lights

To your question - its a minority of cars but big enough the forums talk about it with similar frustrations to the Cayman forum.

Enough cars for a clear pattern as to why to form

The marques forums have lots of pointing at the push back, frustration at what seems like a known design issue not being resolved and people saying that there are enough of us its a known problem and the relevant centers acting dumb even when you show them the forum posts with ex engineers explaining the cause and design defect...... Sound familiar?

One difference is the marque are trying to fix them under warranty unless you have actively done something silly - but the warnings they are giving is suggesting that largess may not last too long.

Most seem to get the same story, told its something you as a driver have done by using it as a daily car that you drive normally for a chunk of the time........

Again it seems if you thrash your cars there are less issues - nearly 13k miles to my next second issue versus 8.5k for the first and it did regen in the garage with some effort. Was in part due to me driving the car more in keeping with it's marques reputation

But message here for Porsche owners with GPF/OPF make sure you give your car a regular ragging when fully warm and use the gears to bring its speed down - seems to be the key to preventing the OPFS finally clogging up.

Its almost like back to the days of carburetors..........
 
Hi Okellyt,

Without Prejudice

Thanks for your interesting post regarding your GPF experience, your premature GPF failure is similar to our journey on our vehicles.

In the miles you have covered have you ever seen a GPF soot regeneration warning light or message on your dashboard.

Is this documented in your drivers manual, and was it explained to you when you purchased the car.

When your car was built the manufacturer had to submit a detailed account on how the new emission system would work and comply on your engine. This is required to obtain a certificate of conformity.

Without this certification the vehicle could not be sold and driven on our roads.

You would expect that one of the first questions on the emission system control would be, how would the active soot regeneration system work and what warning light or message would be used.

Afterall, driver intervention is required to help the exhaust temperature get to the required temperature to burn off the soot accumulated in the filter.

Having followed other GPF issues on other petrol vehicles built from 2019, this seems to be a major problem, no active soot regeneration warnings, only a warning light and message, which usually leads to a GPF replacement.

So these petrol particulate emission systems are failing at the first hurdle, and the Dealers are telling us that we are not driving them correctly, using the wrong oil, and now they are making us aware of a page on the Vehicle Analysis Report that records vehicle journeys.

This information is to backup their reason for the GPF filling up with Ash, and the reason why its needs to be replaced.

Yet, when you look at our data on the GPF filters that have been fitted last year, the oil ash % levels are starting to increase at at alarming rate.

This surely shows the the original diagnosis to replace the filter may not have been correct, I have said many times that the exhaust back pressure needs to be confirmed before the exhaust is removed.

We have recently checked several Cayman 718 vehicles with the DTC P242F oil ash level exceeded and they had no exhaust back pressure at all.

Also the differential pressure sensor readings where very low, which also confirmed no significant back pressure on the exhaust.

I know I am repeating myself again, but none of the vehicles I have been involved in over the last year showed the necessary high differential pressure to confirm the exhaust was blocked.

To sum up again, why are the dealers not checking the exhaust back pressure before they speak to Porsche Technical.

Why are the drivers of these cars not seeing the (Regenerate particle filter see Drivers Manual) message on the information display, when the GPF filter says it is at 100% oil ash.

The message will display if the soot values in calculated K211, and measured K221 show readings above 40%.

I have a photo of a dashboard showing this message, again we have not seen any soot values, in any of these faulty cars over the last year that have been over 8%, measured.

Usually you see data in the measured value, and zero in the calculated, the calculated K211 is the ECU reading that would normally put the regeneration message on the dashboard.

I have lots of GPF reports showing 0.00 % in both soot values, on cars that required a new GPF Filter and have had one replaced last year.

Its no wonder the soot load message is not coming on correctly, this needs looking into.

We will be asking for a exhaust back pressure check to be carried out when these cars go in with the fault code P242F oil/ash load 100% starting this month.

Sorry to go on again, but 2 more Cayman drivers have joined our group over the Christmas period, and I will be supporting them has usual.

Regards
Dave
 
Hi Guys &Girls
Without Prejudice

Sent out a post today on the 718 forum detailing some more technical information on our GPF filter problem.
One of their members replied asking how was the club doing in speaking to Porsche direct about this issue.
This is my reply

Mickster64

Without prejudice

I understand they have tried but at the moment we have no feedback.

Good news is we currently have 29,000 views on this subject, its getting a lot of attention at the moment.

We are looking at the software at the moment to see if we can fix this issue, it would be great if Porsche could help us.

I had two owners contact me over the Christmas period who have been told they need to find 8k to fit a new filter on their cars.

They need to stop this, if no exhaust back pressure is found, why replace the exhaust.

When they fit a new filter they re set the oil ash % level, but they have to regenerate the new filter.

Surely they should be able to reset the oil ash level like they can do on the VW GPF cars easily.

If the dealers are selling these cars the GPF oil ash level needs checking before the car goes out.
They then could speak to Porsche Technical and sort the car out before it goes out.

Remember the engine light with code P242F comes on when the ash level reaches 100%.

The differential pressure sensor measures soot, the engine management measures the ASH.

This will save are new owner drivers a lot of stress and definitely save me a lot of work.

Kind Regards

Dave
 
Hi Guys& Girls

Without prejudice

Following on from my last post regarding exhaust back pressure on our GPF filters.

Found this on YouTube, it shows you the function of the differential pressure sensor and how important this sensor and its readings are to the emission device on our cars.

See link below.

I know I go on about checking for back pressure when these cars are reporting the 100% oil ash load, and the need to change the filter.

But if the differential pressure sensor information is correct, and reading are very low, then we have the answer.

Normally if a filter is starting to get quite blocked, you would see a reading at tickover between say 10 to 100 HPA.

If you increase the revs to between 2.5 and 3K you may see 250 to 300 HPA.

In the last 2 days I have seen sensor readings no higher than 4.0 HPA convert this to PSI and you get 0.058 PSI.

I have said many times that the data we are seeing on these GPF filter reports page 42, make no sense at all.

Yet the dealers and Porsche seem to be ignoring the wrong information that's recorded on their report, and it's been the same on all the GPF reports I have seen over the last year.

Let's use the information we have and start looking at the real issue.

We have Cars that had filters fitted last year, that already have high oil ash % figures recorded and they will be going back into the dealers for them to have another look at this problem.

We could save Porsche alot of money if we check the actual back pressure before the exhaust are removed.

Sorry to go on again

Dave


 
Well as you know Dave my car is back in next week for further investigation work following its first VAL check that showed a reading of 27% Ash after 500 miles of driving with a new filter being fitted under warranty along with a new sensor.

I believe at the time my car may have been the only one that had both parts fitted at the same time ?

I must say the Principal at the dealership has been very supportive, along with his team of Gold techs.

With the additional tests and questions that we have requested hopefully this will help find the root cause we are all seeking.

Let’s hope we can use this as an opportunity to finally find a solution to this ongoing issue.
 
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Morning Paul,
Looking forward to getting some positive results and explanations, fingers crossed.
Have a good weekend, catchup soon
Dave
 
Hi Guys & Girls

Without prejudice

Two more 718 drivers contacted me over the weekend with GPF issues asking for advice.

Both had the usual oil ash loading at 100%, and the GPF needs replacing.

Usually when your filter gets to 100% and the warning light comes on, you will be told the GPF needs replacing because its blocked with ash.

What you are not told is that something doesn't seem right with the differential pressure sensor reading that monitors the pressure in your GPF.

It looks very very low.

Well, it could be a faulty sensor.

Let's manually check the pressure in the GPF which will confirm the sensor reading is accurate.

Good idea, worth a look

A differential pressure sensor reading of 6.25 hPa was sent to me last week on a GPF filter that was showing the usual 100 % oil ash loading.

If you convert 6.25 hPa to PSI you get 0.09 PSI.

So no pressure at all

Why are we not looking at this in more detail.

It's been the same on all the cars I have been involved with, that required new filters, and its continuing to be the same on these cars going forward into this year.

Just a thought

Kind Regards

Dave
 
A (non) update. So far the club has not been able to get any answers from Porsche GB or Gmbh on this issue. We are now focussing on simply trying to get a technical representative to read this thread, or at least the later pages, and to comment on what is going on. If we can achieve that we have somethiing to work from.
 
A (non) update. So far the club has not been able to get any answers from Porsche GB or Gmbh on this issue. We are now focussing on simply trying to get a technical representative to read this thread, or at least the later pages, and to comment on what is going on. If we can achieve that we have somethiing to work from.
Hi John,
Disappointing to say the least that the owners club sounds like it has no leverage with the Brand given the number of loyal supports that are members.
As we haven’t seen anything in the monthly mag for a few editions apart from a very small paragraph, why don’t we look at a double page spread in next months, I am sure David is more than capable of writing a very factual article that would grab the attention of the brand if that is what the club are trying to achieve?
You could even ask for some of those effected by this situation to add their journey so far to give David’s article some real world credibility.

More than happy to donate my copy to a local dealership service area for customers to read that maybe are not enthusiasts and purely buy based on the brand recognition/kudos created by us the brand sponsor’s..

Surely it’s got to be better for the club to go to press with an article on this matter rather than another non brand mag ?

My understanding is that this post is up to over 30k views… must be the biggest story in years.
 

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