Cayman 718 GPF Failure

[Cyclemotor1958]

Hi Guys & Girls

Without prejudice

I know we have talked about this many times, but this Ash issue we have on our cars should show itself before it gets to 100%.

If the soot load is monitored by the differential pressure sensor, then the soot regeneration warning light and message should have been triggered well before the Ash message comes on.

But on our cars the soot regeneration information in the drivers manual doesn't correspond with what comes up on the dashboard.
You will see in the photos below what I mean, now bearing in mind the soot load warning message as never been seen on any of our faulty cars, so the basic soot load driver information is incorrect on our cars.

You would expect a GPF filter thats supposedly blocked with Ash, would have difficulty in accommodating the soot volumes generated by normal driving.

You would also expect some soot to be present when the filter is saying its full, and you never see a differential pressure sensor reading that would indicate an high enough pressure to put the soot light on.

And also, as the GPF Filter starts accumulating Ash, why isn't the pressure increase picked up by the soot sensor as it increases.

All we get is a engine light on, and a message saying, ENGINE CONTROL FAULT, CONSULT DEALER, DRIVING PERMITTED.

So these cars do not have a working pressure sensor, that puts on the soot warning light and the message, so that the driver can carry out his own regeneration of the GPF filter.

Enclose a photo of the Particulate filter Regeneration message you never see below.

Sorry this post contains a few photos of information received from Dealers on our cars, if you are not a member of the club you may not see them.

One of these photos shows you a written response from Porsche Customer Care relating to the function of the soot warning light as Porsche Technical understands it.

This is the car that Porsche Customer Care also confirmed that the Ash load issue was indeed a manufacturing defect, we have the case number to support this.

Also in the Porsche internal memo, it instruts the Porsche technicians to check the functionality of the GPF differential pressure sensor.

So you would normally check the pressure readings at idle, at at 2.5 to 3.0 rpm, if the filter was blocked you would see the pressure increase dramatically, because you would be producing more soot.

We are fed up of asking our Dealers to check the back pressure on our cars because they will not do it.

But if you think about it, they are not even following the Porsche instructions as written in the internal memo.

If they did, they would find no Backpressure, and no need to replace the filter.

Also enclosed is a photo of a recent VHC check showing what the Dealer found and whats needed to be done on this Cayman 718, the PPN is the internal document instructions they follow suggesting a regeneration does not burn off the Ash.

Whats really incredible is the Ash can disappear and can come back on these cars, and our Porsche Ash sometimes can be burnt off, its a miracle.

What are the reasons for our Dealers not doing the correct diagnosis of a suspected blocked filter with ASH.

We would like to hear them, perhaps Porsche Technical Reading could help us with this question, because the Dealers won't tell us, they blame Porsche Technical.

Fingers crossed

Dave

 

[Cyclemotor1958]

Sorry, everybody

Technical issue with my photos

Dave

 

[Cyclemotor1958]

Hi Guys & Girls

Without prejudice

This is the Customer Care letter that was sent to the owner of the vehicle I mentioned on the previous post.

Just to mention the owner of the vehicle also me the VAL report showing the DTC P242F ash load high present.

The owner has given me permission to use this information on our forum.

It took us over 5 months to convince Porsche Reading that the technical information regarding the GPF values made no sense at all.

So it was replaced free of charge, the original quote was over 9K.

The owner of this vehicle sold the car because the Ash came back, and did not want any more stress.

So here is this document with its case number to prove its correct and its not made up.

I will leave you all to draw your own conclusions.

Dave

 

[Wrightrubber]

Hi Dave

Without Prejudice.

As discussed many times previously, if this vehicle experienced the same issue and the same codes as all the other vehicles and it was deemed a manufacturing defect then all the others must be a manufacturing defect!! They have no excuse but to replace them FOC and stop this stupid charade of trying to charge owners £9K and sort it once and for all!

Regards

Mark

 

[911hillclimber]

I have not seen any evidence they have a solution.

 

[Cyclemotor1958]

Hi Voodoo_Blue

Without prejudice

We are just waiting for some information to come in from some Dealers regarding the correct diagnosis of our GPF filters on cars with reoccurring ash values.

These cars have had the new modified filters fitted, and the ash has come back, we have seen values exceeding 75% on one car, which we are monitoring.

If we get the usual answer, there's nothing wrong, and this is exceptable and no further work will be done on your car.

We will look to escalate this further and we have plans in place, and all the data to push on with this.

Dealers are still trying to charge for these new modified filters, even though they have paid for them over the last 2 years with our intervention.

We have 138 thousand views on this GPF subject at the moment and a big thankyou to everyone thats looking at our forum.

Many thanks

Dave

 

[Cyclemotor1958]

Hi 911Hillclimber

Sadly I think you could be right.

Once one of our cars thats had a new modified filter fitted, and the Ash light comes back on again, with the same DTC P242F, then its game over, we just need one car to fault.

We are monitoring 5 cars at the moment so let's just see what happens.

Dave

 

[Cyclemotor1958]

Hi Guys & Girls

Without prejudice

Sadly had another owner contact me last night with a Cayman 2.0 2019 car with the DTC P242F oil load exceeded.

He was quoted by the Porsche Dealer who sold him the car, he was quoted £9,300 to replace his GPF.

The frustrating thing is this Dealer is know to us, a year and a half ago this Dealer fitted a new modified filter to one of our cars, after our intervention.

Unfortunately the ash came back after we checked it twice and it was increasing, the last reading was 64%.

Because of this the owner sold the car because of all the stress and inconvenience, and his relationship with the Dealer was terrible.

Many people have said to me that we should name and shame these Dealers, but unfortunately while this owner is trying to get some help we have to hold on.

If there is no help we may make everybody aware of this Dealer, they know these filters do not fix this fault, so why are they trying to charge for this repair.

Will keep you informed has we go along.

Dave

 

[Cyclemotor1958]

Hi Guys & Girls

Without prejudice

Well, we are really struggling at the moment trying to get our Porsche Dealers to carry out a basic back pressure check on cars that they say require a new GPF filter.

As you know when these cars show the DTC P242F (ash load exceeded), the Dealers have to follow the internal memo instructions that came out last March.

Below is the checks the Dealer has to do word for word.

Several causes of the high ash load have been found across various vehicles therefore to prevent repeat issues it is important to check all possible causes of high ash load before proceeding with any repair. These include completing cylinder leakage checks to ensure oil is not entering the cylinder, checks of the intake and exhaust for signs of excessive oil build up which could be a result of a leak from the oil separators, turbocharger or valve stem seals. Itis also important to check the operation of the turbocharger actuator to ensure this is functioning correctly and check the OPF differential pressure sensor for correct functionality ensuring the pipes to the diferential pressure sensor are not blocked or restricted.

It clearly says: check the OPF differential pressure sensor for correct functionality ensuring the pipes to the differential pressure sensor are not blocked or restricted.

The only way you can check the pressure sensor functionality on a vehicle thats displaying a blocked GPF filter with ash or soot is to connect a separate pressure monitoring device to the supple pipe to the sensor from the GPF.

This will give you a direct pressure reading from the GPF, which you then can compare with the cars reading.

If both readings are more or less the same then you have the correct diagnosis regarding the actual pressure in the GPF.

Now bearing in mind that all of the cars that we have been involved in that had the P242F code present, all without exception had very low pressure readings from the differential pressure sensor and no soot present.

SO WHY ARE THESE PORSCHE DEALERS NOT CARRYING OUT THIS SIMPLE CHECK TO MAKE SURE THE CORRECT DIAGNOSIS HAS BEEN CARRIED OUT.

AND WHY ISNT PORSCHE TECHNICAL MAKING SURE THAT THEY CARRY OUT THE CORRECT DIAGNOSIS OF THIS FAULT.

THE FACT THAT THIS BACK PRESSURE CHECK WASN'T WRITTEN IN THE CHECKING INSTRUCTIONS SHOULDN'T STOP THE DEALERS DUTY OF CARE TO THEIR CUSTOMERS.

THE AVERAGE QUOTE FROM THE DEALERS TO REPLACE THESE GPF FILTERS IS AROUND 9.3K.

Thats an awfull amount of money, and to make matters even worse these GPF filters do not need replacing.

Why are our Dealers and Porsche doing this to their customers, this can not carry on.

We are monitoring quite a few of these cars that have had new modified filters fitted, paid for by Porsche, where the ash % has come back and is increasing.

When the warning light and the code P242F comes back, somebody will have some explaining to do.

I believe the fact that this Ash % level is increasing on these modified filters clearly shows that Porsche need to investigate this further, because the modified filters are not fixing this issue.

We are aware of a vehicle that had a new modified GPF fitted, a while ago, and the ash came back, the owner apparently went back to the Dealer several times to rectify the situation.

Unfortunately they couldn't fix the car so he sold it, he lost quite alot of money and to make matters worse he was made to pay for this GPF filter replacement, no help from Porsche.


THIS IS A MAJOR MISS-DIAGNOSIS OF A FAULT ON THE EMISSION CONTROL SYSTEM ON THESE CARS, IT NEEDS TO STOP NOW.

Dave

 

[Cyclemotor1958]

Hi me again,

Without prejudice

We haven't talked about the effect a blocked GPF filter will have on the rest of the emission system, found this information on Google.

Here is how a blocked GPF affects NOx control and emissions:

1. Increased NOx Emissions (Reduced Catalyst Efficiency)
Reduced Catalyst Activity: Many modern GPFs are coated with a Three-Way Catalyst (TWC) to handle both particles and gas emissions (CO, HC, NOx). A heavily clogged GPF reduces the overall active area available for chemical conversion.
Chemical Poisoning/Masking: Ash buildup—particularly Calcium, Phosphorus, and Zinc from lubricating oil—can mask the precious metal sites (platinum, palladium, rhodium) on the catalyst, reducing its ability to convert NOx into harmless nitrogen.
Temperature Impact: Ash deposits can alter the thermal characteristics of the filter, potentially increasing the "light-off" temperature (the temperature at which the catalyst becomes active), meaning the catalyst takes longer to start working, increasing cold-start emissions.

2. General Emission and Engine Performance Effects
Increased Backpressure: Ash is incombustible and cannot be removed by normal regeneration (burning off soot). This permanent blockage causes excessive backpressure, forcing the engine to work harder.
Poor Engine Performance: High backpressure restricts exhaust flow, causing reduced power, poor acceleration, and decreased fuel efficiency.
Higher Overall Emissions: If the GPF is blocked, the engine management system may struggle to maintain stoichiometric conditions (the perfect air-fuel ratio for the catalyst), leading to higher emissions of HC, CO, and NOx.

A petrol vehicle with a Gasoline Particulate Filter (GPF) showing a false or incorrect ash value can affect engine management, which may lead to indirect effects on NOx emissions, though the primary impact is on particulate number (PN) emissions and overall exhaust backpressure.

Here is how an incorrect ash value affects the system:
Improper Regeneration Strategy: The ECU uses the reported ash value (along with soot loading) to determine when to trigger GPF regeneration (burning off soot). If the ash value is falsely high, the car may run unnecessary or overly frequent regenerations.
Impact on NOx: Excessive or improper regeneration can lead to increased thermal loads on the Three-Way Catalyst (TWC), which handles NOx, CO, and HC. If the GPF is integrated with the TWC, a false, high ash value can cause "over-regeneration," potentially impacting the catalyst's ability to reduce NOx effectively under certain conditions.

Increased Backpressure: Ash is non-combustible material that builds up over time and increases backpressure. An incorrect ash value prevents the ECU from accurately managing this, potentially causing excessive backpressure, which impacts engine efficiency and can lead to higher engine-out emissions.

Decreased Fuel Economy: An incorrect, excessively high ash value can trigger more frequent, unnecessary, and hotter active regenerations, which increases fuel consumption.

So if our filters are indeed blocked you would expect to see issues with the exhaust emission readings, because the Catalytic Convertor would be restricted by back pressure, because of the blocked GPF.

Just a another check that could be done to correctly diagnose these GPF filters.

Dave

 

[911hillclimber]

And the MoT man will certainly see this and fail the car? (light on dash or not)

 

[Cyclemotor1958]

Hi 911Hillclimber,

Thanks for your reply

Well we know that the emissions should be ok, because the GPF filters are not blocked with Ash.

It just a shame the Dealers and Porsche obviously don't think like we do.

Its their cars, their fault, and their customers that are suffering afterall.

If they continue to carry on with this nonsense, they will lose the loyalty of customers who love these cars, and that is not acceptable.

This is not going to be another IMS, BORESCORING fault thats not fixed.

This is an emission control defect that needs urgent attention. It was urgent in 2019 when a modified GPF was fitted to post December 2019 cars for the same DTC P242F we are seeing now.

We push on
Dave

 

[Wrightrubber]

Hi Dave

How can they continue to get away with it when you have evidence that they knew about this in 2019 (re the memo) and you have evidence from Porsche to say it was a manufacturing defect, yet they still want to charge in excess of £9K, disgusting!!

Mark

 

[Cyclemotor1958]

Hi Mark,

Yes we have all this evidence, and we have some more evidence that confirms 100% that these modified filters have not fixed this issue.

Regarding this evidence, we cannot make it public at the moment, because its connected to one of our owners down south who's trying to get answers to why his oil ash % has come back on his new modified filter.

What we need to do is arrange a meeting with Porsche Readings Technical department to discuss this ongoing problem, we have nearly three years of data, with all the gathered information to challenge Porsche with this manufacturing defect.

I will speak to John from the Porsche Club to see if he can arrange a meeting.

We are also speaking to Trading Standards about this issue, and other organisations.

We will update you all has things progress.

Dave

 

[Cyclemotor1958]

Hi Guys & Girls

Without prejudice

Sorry its been a while since we last posted, but we have been busy trying to get our Porsche Dealers to carry out a simple back pressure check on GPF filters they are still saying need replacing due to this Ash issue.

The average cost at the moment is around 9K.

Along time ago we had this ASH issue on a vehicle that was maintained at Porsche Centre Reading.

The owner was quoted £9,172.00 to replace the GPF filter.

We asked for the GPF report, and we found the differential pressure sensor reading K251 was showing 0.00 hPa.

We then asked them, why was very little soot present on the report, and why if the filter was supposedly blocked with Ash didn't the soot warning light and message come on. And why is the differential pressure sensor showing no pressure at all.

Afterall if the filter was blocked with ASH where would the soot go to.

We then spoke to Porsche Customer Care and asked them the same question, and they sent us a response from the Technical Department, enclosed below.

If you read the letter, it clearly says what should happen, and what happens when the filter starts to clog.

The differential pressure sensor can not distinguish between ASH or SOOT, its function is to monitor pressure inside the filter.

When we look back at all the cars we have dealt with, we have never seen this soot regeneration message, photo below.

We only got this photo because one of our owners, after being told he needed a new GPF filter, arranged for the filter to be cleaned out.

The used a very aggressive cleaner, and it temporary blocked the filter putting on this message with the fault code P2463, see photo below.

It took us over 5 months to get this vehicle repaired, and Porsche paid for the repair in full, thankfully, and it was appreciated.

Customer care sent a final letter of explanation to the owner with confirmation that both the Technical and Warranty teams identified that this fault to be a manufacturing defect, enclose for your attention below.

All we need is the Dealers to carry out a simple back pressure check from the GPF supple pipe to the sensor using a manometer set to the hPa setting.

This will confirm what the sensor is telling the ECU, if the back pressure reading is the same has the cars reading, then the car doesn't need a new modified filter.

Why would this simple check not be done, why isn't the soot warning message coming up on our dashboards, and why is soot never present when these filters are supposedly blocked.

We could also check the intake vacuum reading, because a blocked GPF would decrease the intake vacuum, because the exhaust gases cannot escape efficiently, the buildup of pressure would cause a bottleneck effect, reducing the efficiency of the engine’s intake stroke, therefore reducing vacuum.

Again another simple test that could be done to finally confirm these filters are definitely not blocked.

If this carries on, we may have to speak to the Trading Standards and Motor Ombudsman for their view on this subject.

The "satisfactory quality" and "fit for purpose" standards under the Consumer Rights Act 2015 can be applied to Motor Dealers and Garages for service and repair work. Repairs must be done with reasonable care, and attention.

Dave

 

[911hillclimber]

Seems to me there is no other route now but to involve Trading Standards (etc) to get things moving.
If you go to them I hope you will get the support.

 

[Wrightrubber]

Hi Dave

Without Prejudice

Why won't they carry out these simple tests? I suspect Porsche won't let them do them because it will prove definitively that the filters are not blocked and that will throw the spotlight on the software and the defective system of monitoring it!
Have you had any joy with arranging a meeting with Porsche's Technical Department at Reading?

Regards
Mark

 

[Cyclemotor1958]

Hi 911Hillclimber

Without prejudice

Thanks for your reply, I think this maybe our way forward, its the diagnosis of this fault thats seems to be the problem, and thats down to the Dealers.

If they continue to follow the instructions on the internal memo, then things will not move forward, because a back pressure check was excluded.

The internal memo says model range 718 (982) 2018-19 worldwide.

The Dealers have been told to check the functionality of the differential pressure sensor, and to even ensure that the pipes to the differential pressure sensor are not blocked or restricted.

But they are adamant that a back pressure check is not required, it doesn't make any sense at all.

When we asked our Dealers why are they refusing to do the test, they say its not part of the Technical instructions they have been told to follow.

Why is it, that we are thankfully not seeing this ash issue on our 4.0 cars fitted with GPF filters, same model year.

They are both built to an Emission standard, yet are cars seem to rely so much on calculation and measured data. The only sensor that reports an actual value is the differential pressure sensor.

Our cars do not have an exhaust temperature sensor fitted, and have a combined Catalytic Convertor with GPF, and an algorithm that cannot function correctly because these cars have no adaptation facility to reset set the differential pressure sensor, and GPF basic values to zero.

This is essential when new parts are fitted, this issue would be considered a defective system issue, which is a maintenance issue that must be repaired.

The fact they have to carry out a soot regeneration to try and reset Ash % values is ridiculous, and we have proved that on these cars that have had new modified filters fitted, the ash % values are coming back at a rate thats not exceptable.

It even says in the memo, that if a customer complains of the EML light on the dash, and in some cases his vehicle may have a reduced power output, then the Dealer needs to follow the memo instruction.

We have never had any of our owners with this fault, mentioned reduced performance, or any other issues associated with this DTC , in all the cases we have dealt with.

It goes on to say if the fault code P242F is present and the filter is at 100% the Dealer has to follow documented checks based on a theory that oil is entering the combustion chamber via the crankcase ventilation system, which would form ash particles over time.

They then go on to say that they have seen several causes of high ash load across various vehicles, so therefore to prevent repeat issues, it is important to check all possible causes of high ash load before proceeding with ANY REPAIR.

The things to check are a cylinder leakage test, looking at intake and exhaust valves for signs of oil.
Oil separators, turbocharger, valve stem seals, has well as the differential pressure sensor function.

All these tests are specifically looking for reasons why these GPF filters have filled with ash prematurely.

A reduced power output would certainly be the case if the GPF was blocked

I was told a few years ago from a Dealer technician that when a car came in with a suspected GPF fault they used a simple percentage check to determine if they should carry out a regeneration, or just replace the Gpf.

Level 4 = 64% to 85% could attempt regeneration.
Level 5 = 86% to 99% replace the GPF
Level 6 = 100% replace the GPF.

The internal memo came out last March and it clearly outlines checking procedures to be carried out to determine if the GPF is indeed blocked.

Could it be that before the memo, these suspected GPF filters were just fitted purely on what level the Ash% reading was on.

One little check could have possibly saved Porsche a fortune, stopped our owners who loved these cars from having to sell their cars. Because they couldn't cope with the worry and the the financial cost, which unfortunately forced many of our 718 owners to sell their cars back into the trade.

To be told that the wrong engine oil has been used, the car doesn't have a full Porsche Service history, and your driving style is causing the GPF to fill up with ash, and sadly your Porsche Extended warranty can not help would not be good.

And sadly this is a major miss diagnosis of this fault on these Porsche cars.

How long is this going to carry on.

Dave

 

[Cyclemotor1958]

Hi Mark,

John from our club is looking into the possibility of a meeting with Porsche Technical, no news has yet.

Fingers crossed

Dave

 

[911hillclimber]

Thank you for the response.
World wide issue, so the numbers in other countries must add up to quite a number?

This will go one until the Trading Standards are meeting with them, not the nice PCGB imho.

Keep at 'em!