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Cayman 718 GPF Failure

Hi all,
Without Prejudice.

Please see link to latest Porsche Approved Warranty.

There has been a fundamental change to what is NOT covered, it now states all filters (including Particulate Filters) this has been added. It does not state this on my extended warranty, which begs the question why have they been telling owners that the particulate filter was not covered on cars with extended warranties prior to this change!!

You designed this car with the Particulate Filter incorporated into the catalytic converter making it very expensive to replace and the system to control it doesn't work and your technicians are not checking VAL Data or checking back pressure to prove the filters are full!

Porsche you ought to be ashamed, you are essentially blaming owners for your poorly designed car and then writing the warranty to cover your incompetence.

Regards
Mark
 
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Hi Mark,

No surprises there really given their performance so far.

So questions this raises -
I guess this is for new warranties only as they would have to write out to all current warranty holders as this would be a change to terms and conditions..
A question I have have already raised to Porsche and like most questions raised not had an answer is - given the filter is part of the CAT how do you define that the GPF has failed and not the CAT.
If you have had a replacement GPF then surely that would also be covered by a parts warranty?
If it’s not under warranty any more what’s changed ? And why ?
All of the other items noted are parts that are either consumables or wear and tear items… Are they saying a £9000 item is now a wear and tear part…

So going back to my journey when my GPF failed after 1400 miles of ownership one of my original questions was how do you know the GPF failing isn’t the result of something else failing further upstream like for instance the oil separator…

Well moving on 6 months and a 2nd GPF that is now 43% full after 800 miles the car is now back in having a new oil separator fitted under warranty…

So answers on a postcard please.. where would this sit on the new warranty t&cs
 
Hello, this is Richard, I'm head of coms for the Club and run the magazine. This is fascinating and really needs to be sorted. I've had an email conversation with Paul and John about an article in Porsche Post, which I can write for the March issue if we can get the information and images together early next week. Both the CEO and the FD at Reading have requested personal copies of the mag, so it will go under the right eyeballs. I've also offered to put a stronger version of the article on the website which we can then share on Club social media and fire into non-Club 718 communities too to rally support. Power in numbers. I can also send it to the coms director at Reading with an email that's rather more firm that I can write in the magazine. All technical information, diagrams and pics very gratefully received: richardgotch@porscheclubgb.com. Thanks and have a great weekend. Richard.
 
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Hi Richard,

Without Prejudice

Who are you,

Have you been away from the club this past year, or have you just joined the club.

Your comment saying this is fascinating and really needs to be sorted, I feel is in bad taste, none of our 718 owners would consider this to be fascinating.

Regarding your friends at Porsche Reading and their request to read your magazine article, I suggest they speak to their Service Manager, and the Technical Team and catchup on what is really happening in their Dealership.

Porsche Reading presented a bill for £9,172.00 to one of their customers last year, to replace the GPF, usual reason, not driving it correctly, and unfortunately not covered on your Extended Warranty.

It took me over 5 months to convince them and Porsche Technical that this failure was a manufacturing defect, and the customer should not have to pay.

After the repair they kindly wrote back to us confirming it was indeed a manufacturing defect, and apologised.

Where were you?

We are not waiting for your friends to read your article in the March magazine, we are getting on with this now, and have been working very hard over the past year, to try and get a resolution.

Thankfully we have managed to stop the dealers and Porsche charging our owners for work that should be covered under warranty.

You don't need any diagrams and pictures, has I have been posting out since page 5, and all the technical information is available for you to read, perhaps your friends at Porsche Reading can do the same.

Don't forget 31K views on this subject.


Dave
 
Hi Richard,

Without Prejudice

Who are you,

Have you been away from the club this past year, or have you just joined the club.

Your comment saying this is fascinating and really needs to be sorted, I feel is in bad taste, none of our 718 owners would consider this to be fascinating.

Regarding your friends at Porsche Reading and their request to read your magazine article, I suggest they speak to their Service Manager, and the Technical Team and catchup on what is really happening in their Dealership.

Porsche Reading presented a bill for £9,172.00 to one of their customers last year, to replace the GPF, usual reason, not driving it correctly, and unfortunately not covered on your Extended Warranty.

It took me over 5 months to convince them and Porsche Technical that this failure was a manufacturing defect, and the customer should not have to pay.

After the repair they kindly wrote back to us confirming it was indeed a manufacturing defect, and apologised.

Where were you?

We are not waiting for your friends to read your article in the March magazine, we are getting on with this now, and have been working very hard over the past year, to try and get a resolution.

Thankfully we have managed to stop the dealers and Porsche charging our owners for work that should be covered under warranty.

You don't need any diagrams and pictures, has I have been posting out since page 5, and all the technical information is available for you to read, perhaps your friends at Porsche Reading can do the same.

Don't forget 31K views on this subject.


Dave
If you think trying to help, or saying that it "needs to be sorted" is "in bad taste," then don't feel you have to benefit from anything I can do. You may not know that diagrams lifted off a forum are not high enough resolution to print. Personally, I think diagrams will help readers and the senior Porsche non-tech leaders understand, but if you feel you know better, then fine. Where was I? I was trying to make Porsche Post a much more interesting magazine for the Members. Richard Gotch, executive editor Porsche Post, head of coms PCGB. Retiring this month as I'm completely fed-up with this type of rudeness. This isn't how our community should respond to people trying to help. Without Prejudice, of course.
 
If you think trying to help, or saying that it "needs to be sorted" is "in bad taste," then don't feel you have to benefit from anything I can do. You may not know that diagrams lifted off a forum are not high enough resolution to print. Personally, I think diagrams will help readers and the senior Porsche non-tech leaders understand, but if you feel you know better, then fine. Where was I? I was trying to make Porsche Post a much more interesting magazine for the Members. Richard Gotch, executive editor Porsche Post, head of coms PCGB. Retiring this month as I'm completely fed-up with this type of rudeness. This isn't how our community should respond to people trying to help. Without Prejudice, of course.
Hi Richard,
Did you see the email I sent you on Saturday?

Regards

Paul
 
I will be working with Richard and Dave to get this article into shape. Yes, it will be necessary to go over old ground, but in an article we have to tell the full story of this issue and set out what we are asking Porsche to do. Dave's work is at the centre of all this as he has put a massive effort into researching this issue, assisting members and saving them £1000's. I will be meeting up with Dave this week, but if anyone else would like to contact me directly please do, by telephone or mail.

Best wishes, John
 
That’s good to know John, and with Richard’s invaluable assistance in getting the matter into print let’s hope that the matter gets a wider airing and with it a more focused attention of Porsche UK and Stuttgart.

Jeff
 
Hi all,
Without Prejudice.

Please see link to latest Porsche Approved Warranty.

There has been a fundamental change to what is NOT covered, it now states all filters (including Particulate Filters) this has been added. It does not state this on my extended warranty, which begs the question why have they been telling owners that the particulate filter was not covered on cars with extended warranties prior to this change!!

You designed this car with the Particulate Filter incorporated into the catalytic converter making it very expensive to replace and the system to control it doesn't work and your technicians are not checking VAL Data or checking back pressure to prove the filters are full!

Porsche you ought to be ashamed, you are essentially blaming owners for your poorly designed car andsuggested that as the original post was started by you it

Hi all,
Without Prejudice.

Please see link to latest Porsche Approved Warranty.

There has been a fundamental change to what is NOT covered, it now states all filters (including Particulate Filters) this has been added. It does not state this on my extended warranty, which begs the question why have they been telling owners that the particulate filter was not covered on cars with extended warranties prior to this change!!

You designed this car with the Particulate Filter incorporated into the catalytic converter making it very expensive to replace and the system to control it doesn't work and your technicians are not checking VAL Data or checking back pressure to prove the filters are full!

Porsche you ought to be ashamed, you are essentially blaming owners for your poorly designed car and then writing the warranty to cover your incompetence.

Regards
Mark
Hi Mark,
I had a really constructive call with Richard today regarding my experiences of this issue, dealership and Brand (Reading) support ,I know that Dave and John are also meeting up this week to discuss technical details. As the owner of the original post I hope you don't mind that I suggested to Richard that it would be excellent for you both to also catch up and for you to share your journey and views as part of the planned article.

Regards

Paul
 
Just spotted another one on the Porsche 718 forum on Facebook that has just had the £9k light of doom..
Looking to delete cat and cancel light, how many others are there out there that have taken this route.
 

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I’m not sure what the implications would be when it comes to getting an MOT [I think that a GPF delete is illegal?], although since the cat and GPF are combined in one unit I suppose the tester would need to be familiar with the 718 F-4T layout in order to recognise this.

A bigger turbo sounds a bit extreme! I’m not aware that any tuner offers this option?🤔 Just a remap with the standard set-up will release more than enough power and torque without resorting to significant brake upgrades.

Jeff
 
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Hi Guys & Girls

Without prejudice

I would just like to share this technical video information with you, regarding the workings of the differential pressure sensor and show you what happens when you apply pressure to the sensor.

This would be the same when the filter gets blocked with ash, or soot.

Remember this sensors function is to tell the ECU when the soot loading in the GPF filter is at a stage when a regeneration is required because back pressure is building up.

I have said on lots of previous posts that whenever we have a GPF filter showing the 100 % ash DTC, we have a very low differential pressure sensor reading, usually no higher than 6.0 hPa, which is no back pressure at all.

If you watch closely on the video he applies a pressure of around 7 to 8 PSI which is around 50 kpa, to the sensor and this creates a voltage of just over 3 volts that's sent to the ECU.

This is converted to a differential pressure reading of 57 kpa which is pressure the ECU is seeing from the sensor.

If you then convert the 57 kpa to hPa which is what are cars sensor works in, you get 570 hPa.

We have never, ever seen a differential pressure sensor reading any where near this level.

And even if you lower the pressure by half it would still be around 285 hpa, still very high.

How can these fiters be blocked when we have such ridiculously low differential pressure sensor readings, it doesn't make any sense.

And why when we have ask our dealers to check for back pressure on our cars do they not do it.

The fact that the dealers are fitting lots of new filters on our cars and the oil ash problem is coming back after very low mileages, clearly suggests that the diagnosis was not correct.

I don't understand why a simple back pressure check is not carried out because this information is crucial to the correct diagnosis of this fault.

It's no wonder we never see the soot loading message on the dashboard for regeneration, when we see these very low pressure sensor readings on a supposedly blocked filter.

Sorry to mention this again, the oil ash measured value comes from the algorithm written within the ECU, and why is there never any information in the oil ash calculated section of the GPF reading report.

We could stop upsetting the owners of these cars, by doing the job right, this would stop the dealers looking bad using the reasons for failure, wrong oil, and to many short journeys.

Porsche Technical could start looking at the software instead of wasting money and time on new GPF filters.

Surley when these GPF filters go back to the manufacturer they will be tested, to confirm they are indeed blocked at 100%, has anyone at Technical checked to see if this is the case.

Dave







 Dave
 

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Hi Guys & Girls

Without prejudice

I had a brilliant day yesterday, met up with John from the Porsche Club and had lunch at our local club meeting place the BlueBell Inn at Arkendale Knaresborough.

We spent some quality time going through all the information we have , looking at lots of GPF reports, and information from our owners trying to focus down on our problem.

We are now up to date from a technical aspect and we have a plan going forward which involves further testing of the relationship between the differential pressure sensor readings and the ECU,s reaction to that data received.

When I got home I had some bad news, one of our cars was in with a dealer, having its oil ash % level checked. It had a new GPF filter fitted last December and covered 1, 200 miles,
unfortunately it now has 43% of oil ash recorded in its filter.

Now that's impossible.

We now have 4 cars, that have had a new GPF filter replaced last year coming back with unacceptable amounts of ash recorded in their GPF systems.

Two of these cars had new differential pressure sensors replaced before the GPF filters were fitted.

So surely now we can say it's not the GPF filters that are causing this issue.

A typical idle pressure reading of a unrestricted GPF filter should be between 6 to 10 hPa, it should not exceed 100 hPa.

A restricted GPF filter checked between 2 to 3K rpm would read between 300 to 350 hPa.

This is were a simple back pressure reading would need to be carried out, because has we have said many times the low differential pressure sensor readings we see on these supposedly blocked fiters doesn't make any sense.

We need to look at the voltages the differential pressure sensor is sending to the ECU.

The sensors voltage range is between 0 and 5 volts, the higher the voltage the higher the pressure.

Normally at idle on an unrestricted GPF you should see a voltage between 0.5 to 0.7 volts, on a partially restricted GPF you would see slightly higher readings.

If tested at around 2K on an unrestricted GPF you should see a typical voltage of around 1.6 volts.

On a restricted GPF you would expect to see a increase in voltage of around 4.0 volts.

This data could be checked by using a voltage meter, or a pico scope quite easily.

Now bearing in mind, that all our cars that have shown a 100% oil ash level in the measured section of the GPF report also have very low differential pressure sensor readings.

So could it be that the sensor is reporting a low hpa pressure reading but at the same time reporting a high voltage reading, which is picked up in the measured oil ash reading, but not confirmed in the oil ash calculated reading, when it should be.

And also it's my understanding that when these new differential pressure sensors are fitted they are not adapted.

Usually when fitting these new sensors you carry out an adaption, which clears historical sensor information in the ECU, and starts afresh with new data on a new sensor.

It clearly makes sense that we look at this in more detail, and stop fitting expensive GPF filters, if no back pressure is found.

We will be shortly looking into this on a faulty car, and hopefully will have some more news.

Could anybody at Porsche Technical at Reading engage with us on this issue, just to see if we're are on the same page.

Regards
Dave and all the 718 owners with this problem.
 
Morning Dave,
Just a thought on how Porsche could resolve this once and for all.

Offer you a consultancy role at Reading for a month working with the techs there and in Stuttgart… I am pretty sure it would push things along.

Just a thought ?
 
If these 'choked' filters are replaced with new at customer expense, what happens to them?
They must simply go in the skip?
If changed under warranted then the faulty part will/might go back to the manufacturer for analysis and report back to somewhere in Porsche (QA Dept?).

If so Porsche will get it's costs back if the filter is proven faulty but the results not issued so the issues is not in the public domain.

Even I understood the tech details of Dave's last post. Looking forward to the PP article and the actions after.
 
Given the recoverable elements in the catalyst, I hope these things are not just chucked in the skip. But I take your point - you would expect Porsche to see if the filter was in fact blocked and determine the levels of soot and ash. But if they do, they don't tell anybody.
 
Given the recoverable elements in the catalyst, I hope these things are not just chucked in the skip. But I take your point - you would expect Porsche to see if the filter was in fact blocked and determine the levels of soot and ash. But if they do, they don't tell anybody.
So when they changed my 1st GPF under warranty I actually requested photos of the inside of the exhaust from the OPC - NOTHING Received.

I also asked if it could be tested to see if it was blocked - both before and after removal.

I also asked if Porsche knew what capacity of ASH the GPF was designed to hold and what the expected relationship of soot to ash was once burnt after a regeneration.

You would like to think the above was all part of the R&D that took place by both the car and GPF manufacturers before going live.

I find it highly unlikely to also find it to be a manufacturing fault with the GPF as 5 years after the original boxes were fitted there are a lot of owners now filling up the replacement GPF to a level where the VAL report indicates a projected 100% fill after between 2000 and 3000 miles after fitting.
I guess these replacement GPFs can’t be from the same manufactured batch give the time difference.

And why the sudden increase in rate of fill … or indication of fill level ?

If it finally turns out these are not full which a simple test would indicate, there’s been a lot of unnecessary money spent by some owners who may have had to pay ,dealerships if they have contributed and the warranty company if they ended up picking up the bill.

That excludes the amount of time,worry and loss of vehicle the owners have had to deal with.

Hopefully the planned article written for next months Post and the internal pressure the club are now applying will galvanise some action that leads to a solution once and for all.
 
Hi Guys&Girls

Without Prejudice

Another faulty 718 joined our group on Monday, usual case of not having the car long, and the light and message came on.

Regarding this message it says DRIVING PERMITTED.

Funny I thought with a supposedly blocked GPF filter showing 100%, it should be quite difficult to drive.

Also a few weeks ago one of our cars was picked up by a dealer and transported to the Porsche garage. The owner wanted to take the car himself, but the dealer said it could catch fire and they wouldn't risk it.

Seems this message on the dashboard needs possible fire risk adding on.

Back to the GPF and what state it's in when the oil ash light and message comes on.
We all know the function of the differential pressure sensor is to tell the ECU when the soot loading is causing sufficient back pressure that needs immediate attention.

Funny that when we get a supposedly blocked 100% filter with ash, the soot regeneration message doesn't come on, remember its a different DTC, (P2463).
Enclose below a photo of the soot DTC and the warning message on the dashboard.

Why isn't the sensor seeing a high pressure, it's function is to measure the soot loading, but surely with the ash reading at 100% we would have a very high pressure in the GPF ?

The ash reading comes from a measured value from the ECU, not the sensor.

We had a 718 in a dealer last week, that had a new GPF filter fitted last year for it's oil ash level to be checked after a 1000 miles.

Unfortunately it had a very high amount of oil ash recorded, but it also it had no soot levels recorded. I checked back on the GPF report when it was diagnosed and it didn't have any soot levels recorded then.

The dealer carried out a regeneration to try and lower the oil ash level, even when no soot readings were present.

Why would they have to do this.

We currently have 2 vehicles in Porsche workshops at the moment, one has had a new filter fitted last year and the other was diagnosed 9 weeks ago.

The dealers have been told to look for signs of possible oil contamination, from inside the engine, Turbo, and the AOS.

What's happening here, they must believe that possible internal oil contamination is causing the ash load to increase, remember 90% of ash is engine oil burnt.

Funny that they are not checking for back pressure in the GPF, we continue to ask for this simple check to be carried out, but to no avail.

If they are looking for possible faults on the engine causing this issue WHY.

We are finding it increasingly difficult at the moment to get the GPF reports on these cars and it's just getting silly.

The owners are fed up with this behaviour, and sadly quite a few of our owners have got rid of their cars, I have a list.

It's unbelievable that this can be happening, the damage its doing to these people will not be forgotten, never mind the damage to the brand, and the dealers.

Why can't these cars be diagnosed correctly, before we remove the GPF, we know from all the cars coming back the GPF is clearly not at fault.

With the fact that the soot regeneration light on these cars is not working correctly as it should do, and these filters are being replaced for nothing its absolutely ridiculous.

It's becoming quite acceptable now for these cars to be off the road for a long long time.

And it's literally taking weeks and weeks to re set the oil ash level on these cars with new filters fitted, we have a big problem.

Any feed back on this post would be appreciated, on the 29th of May this year I have spent 2 years trying to get Porsche Reading Technical to fix this issue. Its a real shame they will not engage with us on trying to find a solution.

Regards

Dave
 

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