Cayman 718 GPF Failure

[julesman101]

2020 (Build date March 2020) Cayman 718S (2.5L) PPF Issue, Mileage 31,000, PDK, Sports Chrono

If anyone is curating stats or lists I'd like to add my experience of the PPF issue with the above car.

1. Averaging 5,000 miles a year of mainly short trips.
2. No early warning particulate light was displayed.
3. At the 6 year svc interval (31,000 miles) had car serviced at independent Porsche specialist and 2 days later the engine check control message "Engine control fault, consult dealer, driving permitted" appeared.
4. Borrowed a friends cheap ODBII reader and I could see a code P0242F which my generic reader read as Particulate Filer Ash Restriction. Reset the code, but it would come back pretty quickly, but not instantaneously.
5. Read the manual, noticed I did not get the early warning particulate light but performed the Italian tune over the next 3 or 4 days. Reset the code but it would appear again.
6. Took the car back to the independent specialist who ran the proper diagnostic tools and it reported 100% ASH. He recommended the Italian tune. Tried it again, no luck.
7. Given there was no obvious degradation in car behaviour or performance I ran the car for a month whilst I mulled over what the options were. Then one day, I filled the car with E5 (rather than my usual E10) and the following day the engine check control message went away.
8. That was a month ago, the engine check light has not returned. I'm not sure whether E5/E10 is any factor in the this, just like the check light coming on 2 days after svc. Coincidences? I'm not sure there is any connection between fuel type and this issue? Anyway, at the moment I'm only using E5 fuel.

Thanks for listening... JD

 

[911hillclimber]

Interesting post.
Such a change could be tried readily if a problem car, light on, has been run for some time on E10, but a good question for all those affected to think about and well worth the try to E5 for a month or so.
I have an old high mileage 987.2 and have run the car on E10 for about 4 or 5 years. I know it has no filters etc.

The UK Gov site approves this car (a 2.9) for E10/E5 and I believe the ECU will adapt the car to the fuel type in the system at a given time, thus the car can adapt to different octane in different countries.

Does the 718 turbo's have the same capability?

 

[Scrounger]

Just looked at my filler cap and it states 98 RON. I think my 2.0 said the same. Personally I'd only run top tier fuel such as Momentum or Synergy.

Dan

 

[Cyclemotor1958]

Hi JD,

If you would like to discuss your GPF issue, please give me a ring on 07769 590119
Dave

 

[Motorhead]

Just looked at my filler cap and it states 98 RON. I think my 2.0 said the same. Personally I'd only run top tier fuel such as Momentum or Synergy.

Dan

I think you’ll find that any modern Porsche, naturally aspirated or turbo, will run safely on 95 octane fuel Dan. The knock sensor(s) will detect lower octane fuel quality and safely retard the ignition timing to prevent destructive engine damage, but 98 octane fuel will be required for full rated power.

Jeff

 

[julesman101]

Inside of my filler cap! Drivers manual says 98 is "Recommended fuel" and that 95 is an "alternative fuel".
The drivers manual also says E5 or E10 can be used, and the ONLY caveat listed is that fuels containing ethanol can lead to increased fuel consumption.

I'm not sure i this is relevant to my PPF issues disappearing, but I am confused why the issue has disappeared if the car was reporting 100% ASH which I thought meant there was no recovery possible.



Anyhow... it's been 2 weeks since the issue apparently disappeared, so I'm breathing easier. and my wallet will continue to take the relatively small hit. JD

 

[julesman101]

Hi JD,

If you would like to discuss your GPF issue, please give me a ring on 07769 590119
Dave

Hi Dave, thanks for your kind offer.
At the moment I don't have an issue but if it re-occurs then I will be in contact.
Once again, thank you for your valuable contributions to this community.
JD

 

[Motorhead]

I think that it just indicates how screwed-up the GPF software is JD, as Dave has suggested all along!

Yours definitely is an interesting case, but whether or not it’s an outlier remains to be seen. Let’s hope that it remains a permanent fix for you which others can follow.

Jeff

 

[Cyclemotor1958]

Morning Guys & Girls

Sorry we haven't posted for a while

I have been doing some interesting research over the weekend with some of my technical friends regarding the role our differential pressure sensors are playing on our cars.

With the help from my friends, and some time spent , we may have some information that may possibly explain why are cars are filling up with this imaginary Ash, its just a theory but you never know.

To anyone who is considering selling their car because of this GPF fault, please don't, we are working hard in the background to find a fix for this problem.

If you're Warning light comes on with the fault code P242F ash load exceeded, you can still drive the car, and usually we have found that around 300 miles or so, your warning light will go off.

Please contact us on the forum if you need any help and advice.


Dave

 

[Cyclemotor1958]

Hi Guys & Girls

Ive had a good day today, I went out for lunch with one of our Cayman 718 owners that was worried about his AOS.

We carried out the check together which confirmed that his vacuum reading was well within specification.

A good functioning AOS reading is between 30 to 35 inches of water, measured with a manometer.

Enclosed is a short video of that test carried out below.

The AOS is mentioned in the Several causes of high ash load paragraph detailed in the internal memo regarding our Particulate filter ash load to high problem.

You can see its very easy to do, and it takes away a potential high cost repair that could be connected with this issue.

We are at the moment carring out tests on another one of our vehicles with the high ash load diagnosis, P242F.

We we have managed again to reset the ash value, not using the Porsche PWIS tester.

We have done this without having to carry out the the normal regeneration method which again is documented in the memo.

Our last attempts at this ash reset only lasted around 500 miles before the high Ash load software reading came back.

We are keeping our fingers crossed.

At the moment our Porsche PWIS diagnostic tester can not reset the filter ash value back to zero. This is necessary when its proven that no physical soot or ash is present in these filters. We know this is the case because we have checked for back pressure, and all our faulty cars had sensor pressure readings far to low to support a blocked filter.

Because the adaptation function is not at the moment available on PWIS its making things extremely difficult when it comes to re setting the ASH values.

Again the memo specifically said check the OPF (GPF) differential pressure sensor for correct functionality.

We are finding lots of sensor issues on these cars that could have a negative impact on the ash load calculation.

And whats more alarming is we have evidence that these sensors are continuing to malfunction on cars that have just had the modified filters fitted.

Why are they not being checked correctly.

We keep you informed of any progress on this ash re set.

Dave

 

[Cyclemotor1958]

Sorry the video is to large, will try and get it to you


Dave

 

[patersont718t]

I appreciate this has already been shared, but the fact that this issue has been highlighted in The Porsche Post and Porsche still refuses to acknowledge there may be a problem is truly baffling. Perhaps they should take the time to read it themselves.

 

[Cyclemotor1958]

Me again,
This is a photo of the AOS vacuum pressure all ok

 

[911hillclimber]

I can only speculate that Porsche are very aware of this issue and the damming proof you have produced that there is a software fault.
Do you know if any other work has been carried out by enthusiasts around the world or is this a 'UK Spec' thing?

Easy for them to carry on regardless and keep all communication channels closed, welded shut.

Maybe this dam has a few leaks as some have had the filter changed FOC, but the problem is just lurking for a re-appearance.

It is no different to IMS, bore scores etc, for Porsche it all goes away in the end.

I think I read that Porsche UK is top of the charts in the JD Power survey? Maybe just for cars under maker's warrantee?

 

[Motorhead]

I think you’re right there Graham, and as you say Porsche have a record of sticking their fingers in their ears and singing “la, la, la” on this type of issue. They had to be dragged through the US courts under a class action before certain 9x6 and 9x7 owners [only MY 2001-2005 it seems] got compensation for IMS failures, and even then Porsche denied any official wrongdoing or legal liability as part of the settlement agreement in 2013.

Keep going Dave!

Jeff

 

[Cyclemotor1958]

Hi Tony, 911Hillclimber,

Yes your absolutely right, the article was well written and covered lots of facts about this issue, but unfortunatly its been forgotten about.

Hopefully the Porsche Post would like to do a follow-up account of where we are now, and what progress we have made, we will need a few more pages.

We hit 200 thousand views on this subject this morning, 2 thousand this week so far, which is brilliant, it just shows the interest out there regarding our push to get this fault sorted out.

Its unbelievable that in this current climate, the Dealers and Porsche are still wanting to fit this expensive GPF part, when they clearly know it doesn't fix this Ash % software calculation issue.

Dealers around the country have customers asking them why has the ash % returned on their new modified GPF filter's, and are still waiting for an answers.

We are concentrating on the UK market at the moment, its keeping us busy, but to us its an issue that can not go away, like the bore scoring problem. Because this fault is becoming a major miss diagnosis problem in its own right.

You only have to read the internal memo that covers this subject to understand why we are bringing it to the attention of people who are affected by it.

We shouldn't be worried about this light coming on when these cars are going in for an mot.

We shouldn't be in position where we are thinking about selling these cars because the cost of this repair, makes no sense at all, and its not needed.

We just need the Dealers to carry out a back pressure check on these cars when the code P242F presents itself.

Then is over to Porsche Technical to find a solution that fixes these cars properaly.

We are desperately trying to fix this issue ourselves, with help from our owners and drivers, we have got this far because of their help, and its always been appreciated, and will continue to be.

Enclose below is our club page showing are views.

We push on

Dave

 

[Cyclemotor1958]

Hi Guys & Girls

Following on from my last post concerning the functionality of the differential pressure sensors on our cars.

Its always been the case that when the fault code P242F appears on our dashboards, and are cars are plugged into a diagnostic tester we always find the following information.

No soot present, the measured ash is at 100% and the differential pressure sensor readings is usually less than 10 hPa.

And no reports that performance or fuel economy are present, in fact the cars are running fine, before the light comes on, and while its on.

We have said for years now that these filters are not blocked with Ash, and we have proved that there is no backpressure present when the light comes on and the car is being checked.

We have checked 3 cars for back pressure, and we didnt find any.

We have checked a Cayman this week, and carried out a differential pressure sensor check along with a back pressure check.

To do this, we connected a manometer into the GPF supply pipe to the sensor, then we connected the car to a diagnostic tester.

We got the engine warm and checked the differential pressure sensor readings on the manometer and the diagnostic testers read out.

You will see from the photograph that our manometer on the left hand side is reading 8.4 hPa and if you look at the testers screen you can clearly see the ash level K231 at 100%.

If you look below at the K251 current differential sensor measured value, you can see its 5.31 hPa, this is the differential pressure sensor reading.

So it's showing two differential pressure sensor measurements with the engine running at idle that do not support a blocked GPF filter.

These pressures converted to PSI are as follows

8.4 hPa = 0.1218316997 PSI
5.32 hPa = 0.0770150387 PSI

So a direct exhaust pressure taken, and a diagnostic testers reading, a conclusive test you will agree.

So yet again, we find no pressure, what we did find on this car was that the cars differential pressure sensor was the original one fitted at the factory and it was showing pressure even when the engine wasn't running, with the ignition on.

These sensors should self zero, and if they don't, it affects the pressure data going back to the algorithm.

When I contacted Stuttgart I wanted to ask them why a simple back pressure test, like the one we have done on this car, and the others wasn't included in the checks on the internal memo.

They passed me on to Porsche GB, they gave me a case number and asked me to contact them if I had anymore information.

Durring that time I tried to contact Porsche Technical several times, and unfortunately, I became a nuisance.

This resulted in me being told I had to stop trying to contact them, which I did.

I was only trying to ask this question

Why wasn't this back pressure check carried out as part of the diagnostic checks on these GPF filters, thats all.

Because if they did, they would find what we have found, no back pressure present.

And if they questioned the low pressure reading from the sensor, and did what we have done to this car, they wouldn't have recommended fitting a new modified GPF filter.

It seems inconceivable that they would ignore these basic diagnostic steps.

We will carry on with our back pressure checks and hopefully they will start to do them themselves and stop this miss diagnosis madness.

Dave

 

[Cyclemotor1958]

Sorry for the dark picture it was taken in the car last night very late in the evening.

I had to black out the cars details, and re photo the photo sent to me.

But you can just make out the shape of the manometer on the left showing the 8.4 reading along with the time 22: 49: 11, very late.

Dave

 

[patersont718t]

Morning Dave,

As you know, Porsche agreed to replace my GPF, but to the best of my knowledge, the differential pressure sensor wasn’t changed after the memo checks were completed.

After just 30 miles, the car was showing 3.14% oil/ash fill. I’ve since carried out a diagnostic check on the differential pressure sensor myself, and I’m getting the same results even with a brand-new GPF fitted. With the ignition on and the engine off, the differential pressure sensor is reading 2.65 hPa and never zeroes.

The car is going back to the OPC with my readouts, along with the information you previously shared regarding the sensor version you quoted.

I’ll also be requesting the diagnostic results for the sensor, including confirmation of exactly which sensor is fitted and, specifically, confirmation that it is not the original suspect sensor.

Thanks again for your help.
Tony

 

[Cyclemotor1958]

Morning Tony

Thanks for the information on the sensor, what you have found is typical of what we have been seeing for years.

For some reason these sensors are being ignored, and yet their function is critical to the information the algorithm needs.

Has you have found out, our cars do not have the adaptation function to reset the sensor or the GPF after replacement which is absolutely ridiculous.

It will be interesting to see what the Dealer thinks of your findings, you seem to know alot more than them about your car.

Again the memo tells them to check the sensor functionality, they obviously couldn't be bothered, But never mind they just fit a very expensive GPF on your car, that wasn't required, and Porsche paid for the their miss diagnosis.

Like all the other ones.

Dave