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Cayman 718 GPF Failure

Dave,

Interesting to note that in that list: “The fix involves a software update.”

Your 718 analysis to date indicates that a software issue is the most likely source of the GPF problem on these cars, so if an update was possible on the listed cars one has to question why not the 718?🤔

Jeff
 
Hi Jeff

Without prejudice

Yes thats another question we will be asking,

My understanding is, that any software or work carried out on a vehicles emission system that causes issues in multiple vehicles, same model, may have to be reported the the authorities who signed off the original emission system.

So the question we will be asking is in 2019, were the authorities aware that a modified filter had been made, to fix our high ash load % issue, reference the Porsche internal memo.

If they were aware, then surely they would need to know that this modification thats been carried out on 13 of our cars, hasn't worked.

The light has gone out, but the ASH % thats come back on all our cars makes no sense at all.

We have to remember all these parts fitted, GPFs, Turbos, AOS, DME, 2 engine strip downs, and even a brand new engine have not corrected this problem.

To say that this Ash value coming back is ok, is absolute nonsense.

If you plugged a PWIS tester into a new 718 in the show room, you should find a zero oil ash reading.

This is because the new car has a new GPF, our cars have had new GPFs fitted, and yet the oil ash reading is back at an unexplained high level.

This fault has nothing to do with the GPF filter, it never had, the evidence we have, speaks for itself

If Porsche Technical could send out to their Dealers, information on why this oil ash % return is acceptable, and then it could be sent out to our owners, this would help.

I know Iam repeating myself again, but we have seen on the 4.0 cars recently between 4 to 5 years old, they are not showing more than 10% oil ash levels.

Another question we need an answer on is, why these cars are so different.

Dave
 
Hi Guys & Girls

Without prejudice

Had some bad news this evening one of our members down south with a 2023 718 Cayman with very few miles had his oil ash % level checked for the 3rd time this year.
Unfortunately its gone up 3 times to over 50 % now.
While he was at the Dealer he asked them to check if his vehicle has the adaptation capability to adapt the differential pressure sensor and GPF.

The Dealer checked and confirmed his car didn't have this function.

He told the Service Manager that he was very worried about this ash level, and the Service Manager told him to blast the car up the road which would reduce the ash.

And if he is worried to come back next year and they would carry out another regeneration.

Our owner has been doing his deacceleration runs when road conditions allowed, durring this year.

He is now thinking of selling the car.

Ive done some research on Ash loading and found several studies on gasoline vehicles with more than 160,000 km have shown that 0.14 to 0.25 mg/km of ash is generated and stored in the GPF filter over that period, which is 40.00 grams of Ash.

So in miles, if we use the same figure, 0.25 mg, convert the 160,000 km to miles we get 99,400 miles x 0.25 mg we get around 25 grams of Ash.

I asked Google Whether 25 grams of GPF ash (Gasoline Particulate Filter ash) is alot of weight.

This is what came back.

In typical automotive contexts, 25 grams of GPF (Gasoline Particulate Filter) ash is considered a very small, negligible amount of weight. GPF ash accumulates over the lifetime of the vehicle, and modern filters are designed to handle much larger quantities.

To provide context:
In general terms: 25 grams is a light weight, roughly equivalent to four tablespoons of gelatin, or five U.S. nickels.

In GPF/DPF terms: A DPF ash mass of around 39 grams is considered on the high side but not yet problematic, while issues usually arise at 45-50 grams. Given that GPFs are specifically designed to accumulate less ash than DPFs and the accumulation process is very slow (over years and tens of thousands of miles), 25 grams represents only a fraction of the filter's capacity.
Therefore, 25 grams of GPF ash is a minimal amount and not a cause for concern regarding filter performance or potential clogging.

Hopefully if my maths are correct, then this again demonstrates that these filters are not blocked with ASH, so why are the Dealers and Porsche telling us they are.

Again they could check the weight of one of our supposedly blocked filters against a new filter.

Dave
 
They would need some good scales for that I think. Not sure what the DPF actually weights, but an old stand-alone cat is several Kgs.

Saying an 'Italian Service' is needed seems a bit crude in this day and age, good for a Morris Minor, but a late model Porsche?
The owner was fobbed-off surely?
The dealer has no real solution because the Factory do not have one either.

Selling the car is understandable while looking at a lot of grief and a £9,000 bill.

Is this a UK spec car issue or is it global?
 
Hi 911Hillclimber

Without prejudice

Thanks for your feedback, regarding your question, is this a UK spec car issue.

The Porsche internal memo explaining what to do if a customer complains of the EML light coming on with DTC P242F- particulate filter ash load to high.

Top right hand side heading Markets/Regions
Says worldwide.

At the bottom of the memo, it says
If there are any issues outside of this model year range or any further questions please submit a PRMS ticket.

Has I said yesterday we have on file a 2023 Cayman with ASH readings of over 50%, hopefully the Dealer has contacted them and raised a ticket.

Dave
 

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Sorry Dave, but your maths is a little wayward. You seem to be multiplying the ‘per km’ ash accumulation figure (0.25 mg) by the number of miles travelled. 0.25mg should actually be multiplied by 160,000km. This yields an ash figure of 40 grams - so a more negative slant than your calculation.
Apologies if this response seems negative, but that is not my intention. I just want the correct figure to be used going forward.
Please keep up your amazing work - your commitment deserves a medal.
 
Hi Mick

Without prejudice

Thankyou, I was a bit unsure when I sent that calculation, at the end of the day there is no ash in these GPF filters, but unfortunately Porsche and their dealers will not admit this is the case.

They know that this issue is software, just look at the other models that apparently had software adjustments to their emission systems in 2019.

If you look at how diesel cars deal with soot, its really straightforward, when the soot builds up, it puts on the warning light to tell you to give the car a good run.

The light goes out, telling you that the soot has gone.

Our cars don't do this, even when the GPF is supposedly blocked with ash, the soot light is never seen.

That's because the software for some unknown reason doesn't see a pressure value in the GPF high enough to trigger the soot light.

Then we have an ash value thats created in the software that is not picked up by the same pressure sensor used for soot regeneration.

So the ash gets to 100%, and the warning light comes on, the Dealers do not check for back pressure to establish, is the filter actually blocked, they then ask our owners to pay for a blocked filter that isn't blocked, cost now over 9K.

This must be one of the worst cases of miss diagnosis we have seen in Porsche history.

And if you think about this, there will be people out there that have paid for these modified filters, and it didn't fix the problem.

How can these Dealers and Porsche treat their customers this way, using excuses, the wrong engine oil as been fitted, or driving style.

And they even manipulated the extended warranty to say these filters are classed as service item so hard luck.

The new extended warranty now as the GPF in the exclusion section of the handbook, written in for all to see.

Again this was ridiculous considering the GPF filters did not need replacing.

This as been a cover up since these cars came out, the internal memo says it all.

Modified GPF filters fitted has standard on our cars from December 2019, they got the diagnosis wrong then, and they've got it wrong now.

Dave
 

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