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Cayman 718 GPF Failure

Hi Mark, and Greenman986s

Without prejudice

Thanks for your posts guys, good feedback is always appreciated.

When think Mark how far we have come since you first posted out about your GPF.

Page 1, May 29th 2023, its taken along time, but have achieved alot.

We have managed to overturn Porsches desision to charge our members for replacing an expensive GPF filter they didnt need.

Sadly we couldn't help everyone with this issue.

We have proved along the way, when looking at the GPF data on these vehicles the data makes no sense at all.

We have struggled in most cases to get this info, but its proved that we were right from the beginning, no back pressure, no blocked exhaust.

The sad thing is we were told that the wrong engine oil, or driving style caused this issue, and it seemed the Dealers believed this was the case, they should be embarrassed.

Just think of all those customers stood at a Porsche reception desk trying to comprehend the news given, that they needed 8K to fix a car that was running ok.

No performance issues, no fuel economy etc, and at that time, no help from Porsche.

We were also told that the Porsche Extended Warranty wouldn't cover the replacement of the GPF, even though it wasn't listed in the exclusion section of the Warranty, funny it is now.

But the worst thing is the Major Miss Diagnosis of this fault, which we can prove 100%, due to all these modified filters that have been replaced, and its still an issue.

We set out over 2 years ago on a quest to help our owners and Porsche and the Dealers with this issue, and todate we have had no response at all.

Shocking, unbelievable you might say, we expect better from Porsche, these are expensive vehicles afterall.

But one thing for sure, we are going to save the reputation of the 718 GPF fitted cars, with or without Porsches help.

We have other avenues to go down, more research to do, please keep checking our forum.

Regards
Dave
 
Hi Guys & Girls

Without prejudice

Hi,
Just had some amazing news last night from our friends on the 718 Forum.

I posted a copy of my July 24th post to them, and it attracted over 19,810 views.


This is amazing, but when will we have a resolution.

Regards
Dave
 
Hi Guys & Girls

Without Prejudice

Good morning

Last night I put a search text on Google has follows, VCDS GPF OIL ASH RESET VALUES.

VCDS (VAG-COM DIAGNOSTIC SYSTEM), is an aftermarket diagnostic and programming tool used for Volkswagen, Audi, and Skoda vehicles, its been out for year's.

This is what came back, a detailed diagnostic path on how to reset the oil ash values on GPF and DPF vehicles, enclose below.

To reset the oil ash value for a Gasoline Particulate Filter (GPF) or Diesel Particulate Filter (DPF) using VCDS, you typically perform an engine adaptation by entering Security Access and navigating to the Adaptation (10) function. After selecting a relevant channel like "Carbon Mass (DPF Replacement)" or "Particle filter initialization" (often associated with the IDE00275 or IDE07903 ID), you save a new value, often 1, which the system may then change to 0. This process is necessary after cleaning or replacing the GPF to ensure the ECU accurately reflects the filter's new state.

Step-by-Step Reset Process
1. Prerequisites:
Ensure the ignition is on, but the engine is off.

2. Access Engine Adaptation:
In VCDS, select the Engine controller.
Perform Security Access (16) by entering the required code shown in the VCDS pop-up balloon for "Adaptation Enabling".
Proceed to the Adaptation (10) function.

3. Select Adaptation Channel:
From the dropdown menu, find the appropriate channel, such as "Carbon Mass (DPF Replacement)" or "Particle filter initialization". You may also look for the code IDE07903 if the descriptive name isn't available.

4. Save New Value:
Save a new value of 1 to reset the learned carbon/ash mass.
The system may automatically change this value to 0 after a successful reset.

5. Verify and Clear Codes:
Check for and clear any fault codes that are present to confirm the process was successful.

Important Considerations
GPF vs. DPF:
The process is similar for both types of filters, as the principle is to recalibrate the ECU's calculated values after a physical intervention on the filter.

After Cleaning/Replacement:
This adaptation is essential to perform after the GPF has been cleaned or replaced to ensure the system knows the filter's current, accurate condition.
Calculated Value:

The ash load is a calculated value, and resetting it ensures the ECU's calculations are based on the new, reset state of the filter.

Looks straightforward, obviously the differential pressure sensor readings would have been checked to confirm no back pressure was present.

Now, when we look at the way it seems to be done at a Porsche Dealer, the oil ash % is re set by attempting a regeneration, even though there is never any back pressure recorded by the differential pressure sensor.

The recent internal Porsche memo, confirms this procedure, as follows.

In some cases the OPF (GPF), can be recovered, therefore a OPF regeneration should be attempted to see if the OPF ash load is able to be reset. If this has already been attempted or the ash load level doesn't reset when the OPF regeneration is attempted then the OPF should be replaced and retested. The new OPF`s (982254400AF) have been modified to prevent this issue.

Porsche`s words not mine.

We also know on Paul's car, when the new modified GPF filters were fitted, and a regeneration was carried out, the oil ash % figures came back.

Could it possibly be that the PWIS system that the Dealers use to diagnosis, and program these cars doesn't have the capability to carry out the reset process required.

If you read through the above VCDS procedure, a REGENERATION of the GPF, or DPF is not mentioned ?.

We have also heard from Dealer technicians that when a differential pressure sensor is replaced on these cars, they cannot carry out a adaptation on that sensor, its plug and play.

The adaptation removes old data from the ECU which is vital for the sensor to function correctly.

We have been pushing to look at the software for quite a while now, after lots of filters have been fitted, and we still have the problem.

This confirms the fault is not the filters, the filters we have dealt with, haven't been blocked with ash.

Maybe its a combination of Diagnostic and software thats stopping this simple oil ash reset to be carried out.

Sorry for going on

Dave
 
For a while now I've been convinced the filter itself is good, it is the software and it's assessment that is wrong, inaccurate or just not fit for the purpose.

Only Porsche Germany can resolve this imho.
This will only happen if this topic is kept alive with straight facts as you have so skilfully done.

Keep at them!
 
Whilst this is just speculation on my part, I am convinced that Porsche know what the problem is and how to fix it. However, the software and other control parameters in the car are part of the specification that was holologated for productions (TUV etc). To change these would be a 'big deal' and would likely involve lots of other settings and potential issues - the knock on effect - which may affect much bigger numbers and be very costly.

One approach to this, which would result in what have experienced so far, is to say nothing and deal with each case on a one by one basis. If there is no common issue to be addressed, then there is nothing to be done about it. This is a strategy that has worked before and ultimately, as cars do get fixed in one way or another, the noise dies down and it all goes away at the cost of a few unhappy punters.

We will try to keep this alive, and any suggestions as to how this may be achieved would be welcome. But ultimately we may have to be happy that Dave's work has prevented members and owners from getting ripped off financially by the OPC network.
 
Whilst this is just speculation on my part, I am convinced that Porsche know what the problem is and how to fix it. However, the software and other control parameters in the car are part of the specification that was holologated for productions (TUV etc). To change these would be a 'big deal' and would likely involve lots of other settings and potential issues - the knock on effect - which may affect much bigger numbers and be very costly.
dieselgate...
 
Morning Guys & Girls

Without Prejudice

Continuing on with our push to get the OIL ASH % fault on our 718 cars resolved, can I share this information with you.

I Googled this search text question this morning.

Would a measured oil ash load that was incorrect be classed as an emission defect. Bearing in mind that the differential pressure sensor reading was very low, and a replacement GPF filter did not fix the issue.

This is what came back.

Yes, an incorrect, high measured oil ash load on a Gasoline Particulate Filter (GPF) would be considered an emission control defect, especially since a new GPF and low differential pressure sensor readings didn't resolve the issue, indicating a potential fault in the system's measurement or management of the ash level, rather than a physical blockage.


Understanding the Readings
  • High Measured Ash Load:
    This indicates the system believes there is a significant accumulation of ash in the GPF, which is a major concern for emission control, as it can lead to reduced performance and increased emissions.

  • Low Differential Pressure:
    A low differential pressure reading (the difference in pressure before and after the GPF) suggests the exhaust system is not significantly blocked. This contradicts a high ash load, which would normally create high back pressure.
What the Discrepancy Suggests
  • Measurement Malfunction:
    The discrepancy between a high ash load reading and low pressure suggests that the measurement of the ash load itself is incorrect, rather than a real physical problem with the GPF's ability to hold ash.

  • Faulty Sensor or Calculation:
    The issue could stem from the differential pressure sensor itself, the software or algorithm that calculates ash load, or other related components within the GPF management system.
Why It's a Defect

  • Emission Control:
    The primary purpose of the GPF is to control harmful particulate emissions. If the system's internal measurement of ash load is faulty, it can trigger unnecessary interventions (like forced regenerations) or lead to incorrect diagnoses, ultimately impairing its ability to function as a proper emission control device.
  • Component Failure:
    Even if the physical GPF is not the problem (as shown by the replacement not fixing it), the failure of the sensor or the system's ability to accurately measure ash load is a failure of the emission control system.

  • Well that certainly covers what we have been saying for a long time, even GOOGLE understands the issue.

  • We are at 87 thousand views at the moment, thankyou all for your time looking at what's going on, its appreciated.

  • Dave




 
Whilst this is just speculation on my part, I am convinced that Porsche know what the problem is and how to fix it. ........One approach to this, which would result in what have experienced so far, is to say nothing and deal with each case on a one by one basis.

Might this also explain why the Club Leadership appear not to have shown any interest in trying to get Porsche to take notice ? Isn't this exactly the type of issue where the Club should be at the forefront ...
 
Hi Guys & Girls

Without Prejudice

Following on from my last post regarding the possible software issue on our cars, I would like to show you some more confusing information regarding the soot and ash control on our cars.

We have said this before, that none of our owners, that have had this oil ash % issue have ever seen a soot regeneration message on their dashboards.

You would expect that a GPF filter that was filling up with Ash would accumulate soot, and therefore put on the soot regeneration warning message on the dashboard before the Oil Ash warning message came on.

This has never been the case, which is really strange, because the function of the differential pressure sensor is to trigger the soot warning light when the soot load is high.

The only time I have seen the soot regeneration message on one of our cars, was when its GPF had been cleaned with an aggressive Diesel DPF cleaner.

This cleaner clogged the filter and it generated the warning light message and the following DTC codes, see photos enclosed below.

Top left
Regeneration warning light on the dashboard, see Drivers Manual.

Top right
DTC P2463 Particulate filter soot load high

Bottom left
GPF data, showing soot values, ash load at 0.00%, and a differential pressure sensor reading at .75 hPa.

Bottom right
Code 26740 Particle filter regeneration needed.

Now what doesn't make sense is that the .75 hPa differential pressure sensor reading would not be high enough to trigger the soot regeneration message.

But yet we have readings of 40.00 % and 52.55 % in the soot values recorded, the highest we have ever seen in the last 2 years.

So what is this sensor controlling, you would expect a lot higher pressure reading from the soot load present.

The last photo shows a typical GPF report from a car thats reporting a 100% oil ash load, and the usual no soot readings in calculated or measured data.

And to make matters worse, we have a minus differential pressure sensor reading on a filter thats supposedly blocked and needs replacing.

Its no wonder we haven't had any reports of a soot regeneration message on any of our cars, because we have never seen a differential pressure sensor reading high enough, and its unclear where the soot load information is coming from.

Its a shame that Porsche Technical will not contact us via the Porsche Club, we need an explanation on why we are seeing this confusing data, and why these GPF filters have been fitted, and for some reason ignoring the information we have posted out on our forum.

We have a database with over 2 years of data on our faulty cars.

We have always wanted to help them fix this issue on their cars, because it needs fixing.

They need to prove to us that that the issue we are finding with our cars, does not come under the heading of an emission control defect has discussed in our previous post 667.



Sorry for going on again

David
 

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I doubt it because even Porsche haven’t…

During my journey of virtually every part being changed at no point could the Brand tell the dealership what the settings should be.. and remember my car was virtually new as they even put in a new engine..etc etc etc …
 
Hi Guys & Girls

Without Prejudice

Following on from my last post, and trying to understand why we have this GPF data that doesn't make any sense.

We never see any soot values on the GPF report when the filter shows 100% ash.

Spent some time on the Internet and found some references to this as follows.

There are no soot values shown with 100% oil ash in a GPF because a 100% oil ash level indicates a critical system failure, rather than a measurable particulate level, suggesting the ash has filled the filter. In such a case, the ash has permanently accumulated and reduced the filter's volume, which prevents it from effectively capturing and burning off soot, or the sensors are unable to differentiate and measure the ash itself.

Understanding Soot vs. Ash
Soot:
This is carbon particulate produced by incomplete combustion, which can be burned off during the DPF (or GPF) regeneration process.

Ash:
Ash consists of incombustible material from engine oil additives that is not burned during regeneration. It accumulates over time, reducing the filter's available volume and efficiency.

Why Soot Readings Are Absent with High Ash

1. System Failure:

A 100% oil ash level indicates that the GPF is essentially full of ash and can no longer function as designed.

2. Reduced Volume and Efficiency:
The accumulated ash restricts the filter's channels, leading to increased pressure drop and reduced efficiency in filtering and processing soot.

3. Measurement Limitations:
The sensors in the system are designed to estimate soot levels based on pressure measurements and other factors. However, when ash levels reach the maximum, they render the normal soot estimation method inaccurate, or the sensors can't distinguish between the two when the filter is clogged.

4. Sensor or System Malfunction:
The "100%" ash level might also be a symptom of a faulty sensor or a system unable to accurately measure the ash load, which itself is a component failure.

When there's no soot value shown despite a high 100% oil ash level, its because the high ash load is what the system is reporting, not the soot level, and the ash itself doesn't register as a value for the soot sensor. A high measured ash load with low differential pressure suggests the ash is present but not blocking the filter. And the system may be using an algorithm that incorrectly represents the ash level, used by the vehicle's computer (ECU) and diagnostic tool (like a PIWIS tester) to indicate the accumulation of ash, rather than a measured soot value.

Surely now with all the information we have, and all the parts that have been fitted by the Dealers in a desperate attempt to fix this fault on our vehicles, the vehicles software needs closer examination.

We do know that an incorrect measured oil ash load that causes the engine light to come on, can be classified as an emission control defect, especially given the low differential pressure sensor readings, and failure of a new GPF to fix the problem.

In a previous post we mentioned that in some American states they insisted on emission control defect warranties for any 2019 vehicles, that were imported into the country.

Obviously they knew that GPF filters fitted into petrol vehicles would possibly need some development time, and there could be teething problems going forward.

These extra warranties covered the vehicles emission systems for periods longer than the standard warranty period, in some states this warranty cover can be up to 8 years, 80, 000 miles.

We would suggest that if you have the DTC code P242F oil ash load exceeded, you contact your local Porsche Dealer to get them to verify the code and the GPF information, reference the internal memo published in March this year concerning this very issue, and the fact that they have known about this issue since 2019, within the first year of production.

The Dealers are still now fitting parts to these cars, that may cause increased oil consumption in the future, and may create enough Ash to be a problem, but there is no ASH and never has been in our low mileage cars.

The Dealers needs to contact Porsche and register another vehicle with this fault, under the heading of a possible emission control defect.

We also need an awareness regarding checking the GPF oil ash % levels on these cars when they come in for service, and when they are sold. A bit like the EV vehicles now getting a battery health check after a few years of use.

We now have 90,000 views on this forum, on this subject, hopefully before we get to 100,000, we may get some conformation from Porsche, that they agree with us, and something urgently needs to be done to fix this problem once and for all.

Fingers crossed

Dave
 
Great work again Dave however for fear of sounding like a broken record, again, Porsche will not offer any form of solution unless it’s brought into the public eye and when I say that I mean the general public, not the closed doors of the Porsche community.

I think the motoring press would have grounds for a great article. I can’t understand what the fear is in contacting them.

Dan.
 

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