Cayman 718 GPF Failure

[Cyclemotor1958]

Morning Jeff,
I have only had conversations with John, regarding our dealings with owners, Dealers, and customer care.
Would really like to speak to somebody at Porsche Technical, we need some answers.
Actually spoke to John last night who is pushing are case to Porsche Cars
Dave

 

[Cyclemotor1958]

Hi Michael,
Thanks for the info, I think if you are concerned about your car, the only thing you can do is speak to Porsche Leeds and get them to check your GPF oil / ash loading.
They can show you the results on their diagnostic screen, you could take a photo and then send it to me.
Iam very sorry that our posts are causing people to worry about their cars, but at the moment we are very busy trying to sort out 2019 car issues.
Yesterday I spent alot of time drafting a letter to Porsche Technical trying to get them to reverse a decision not to cover the cost of replacing a GPF filter they say is faulty.
The main part of my letter was showing data from GPF reports showing incorrect temperature and % readings, without this information we would have no chance to challenge them.
Dave

 

[michaeldowgill]

Thanks Dave. I traded in my 2019 Cayman T 2 litre and I was getting the the same acoustic sounds with no messages on the Multi- Function display. I just wondered if anybody else is getting this warning but no messages. I now carry out the procedure to clean the GPF as described in the manual when I get these warning tones.
Michael.

 

[Cyclemotor1958]

Hi Michael,
These acoustic sounds have been mentioned before, you could ask the service department if you take in your car for the GPF check.
If you have been doing regeneration runs yourself the oil / ash loading should be okay.
If you would like me to send you a GPF report please give me a ring on 07769 590119
Dave

 

[Motorhead]

Michael,

Like Dave I remember the acoustic sounds being mentioned on here, but looking back I note that it was yourself who asked the question back in August [post #202] . However, I don’t recall anyone else posting on this occurrence, although Dave may have come across it with the owners’ he’s assisted.

Jeff

 

[Paul-718gts]

Hi Ian

Without Prejudice

The hand book is well written explaining what happens when a high soot value needs driver intervention.

It's a shame the car doesn’t put on the light, or a message. In all the cars I have dealt with, in the last year no light or message has been seen.

We have unfortunately at the moment a major emission function error on the cars we are dealing with.

We are expecting the soot warning light to work, Porsche technical are insisting it should work, but sadly it doesn't.

But when we look at the soot calculated and measured values, there never seems to be much in, most of the time you only see a reading in the measured section and thats usually 0.00 %.

The only sensor that can trigger a regeneration is the differential pressure sensor and that always shows a very low differential pressure readings.The regeneration will only happen with high soot levels and high readings.

Yet we are being told the exhaust is blocked. A blocked exhaust would show alot higher differential pressure readings.

The only light that warns the driver of an issue is the engine warning light.
This comes on with a permitted to drive message, and a visit to the dealer, if the fault code is P242F , then a potential bill of £7,500.00 is discussed.

We then have to fight with the dealers and Porsche technical to get them to cover this cost, on the grounds this is a manufacturing defect, which can take us months.
This trouble code is nothing to do with soot, its the oil ash/loading thats reached 100%, and when it comes on its to late to save the GPF.

Which is absolutely ridiculous bearing in mind the low mileages covered on these cars.

We have asked all the Porsche service departments who have dealt with our cars to show us this light working, still waiting, its been a year now.

Sorry for going on but all this information is crucial to our argument that something is sadly wrong with our cars.

We just need an acknowledgement from Porsche Cars that they are looking into this problem on their cars, and we don't need to worry.

Dave

Club Representatives -
As Dave’s last paragraph suggests a statement from the club updating its members on the progress to date on this matter with Porsche GB is all I think it’s members are looking for at this point.
It’s been nearly 3 weeks since there was a mention of the committee engaging Porsche and it’s been radio silence since..

 

[Cyclemotor1958]

Hi, its me again,

Without Prejudice

Following on from our discussions regarding the soot particulate warning light that is not working on the the cars we have been involved with.

Porsche Technical have always been sure that this warning light should come on if the GPF filter is clogged with soot.

Enclose a written response from Porsche Customer Care confirming this, on a vehicle that recently had a new GPF filter replaced free of charge.

This was due to a manufacturing defect confirmed by Porsche Technical, because the trouble code P242F was present.

On all the vehicles that had an oil / ash reading of 100%, Porsche Technical advised the dealers to replace the GPF.

I have managed to see the GPF exhaust data, which was suppled by our drivers,
and in all cases they had a very low differential pressure sensor reading.

In fact the highest reading out of 12 cars was 5.64 hPa.

Sorry for repeating myself again but when a filter is blocked, you would always get higher readings than this.

Bearing in mind the differential pressure sensor would normally signal the ECU to start the regeneration process, put on the warning light, and assist in heating the exhaust to burn off the soot.

So if these GPF filters are blocked with ash at such low mileages, why is this happening.

Could it be that incomplete regenerations by the vehicle without the engine management assisting, during low temperature driving is causing the premature ash build up.

This may explain the situation we are in, after all many studies have been carried out regarding ash behaviour in GPF filters. We know what the affect of using the wrong engine oil can do.
It's quite a complex issue, and it's ongoing.

And we must not forget the role the AOS can play in contaminating the GPF with excessive oil droplets.

Back to the light not coming on, a simple check would be to increase the pressure on the differential pressure sensor with a mityvac tool.

These sensors generally run between 0 and 100 kpa, at idle, which is 15 psi.

The mityvac tool has a max pressure of 30 psi, this range should be enough to put on a warning light, or a trigger a diagnostic trouble code.

The only issue that we have had recently on some of the vehicles that have had replacement GPF filters fitted, is
the dealers found it difficult to reset the oil ash % level back to zero.

So if we could get the dashboard soot warning light working.

Check for exhaust back pressure, to confirm that we need to replace the GPF.

Check the function of the differential pressure sensor and its affect on the upstream temperature reading T251.

Find a quicker way of re setting the oil / ash reading %.

Start checking the AOS vacuum readings on these cars with a manometer to stop oil contamination hitting the GPF.

Then hopefully things should be alot better.

Sorry for going on again

Dave

 

[Paul-718gts]

Club Representatives -
As Dave’s last paragraph suggests a statement from the club updating its members on the progress to date on this matter with Porsche GB is all I think it’s members are looking for at this point.
It’s been nearly 3 weeks since there was a mention of the committee engaging Porsche and it’s been radio silence since..

Club Representatives
Yet another post by David providing some more detail and a method to help the manufacture in its diagnostics … And still no updates or a communication from either the club of Porsche GB on this matter ???

 

[Wrightrubber]

How much more technical detail does Dave need to share for Porsche GB and the Club to listen and be proactive in dealing with this issue...it is not going to go away!! Porsche Technical are still insisting the filter light will come on to alert the driver a re-gen is needed and to drive it in a certain manner....why then when asked on numerous occasions can't they not show this light illuminated..........because it does not work!!

 

[JohnCRS]

I have been working with Dave throughout this period and can assure you that the club is trying its hardest to engage with Porsche. The Chairman has written directly and is pushing for a reply but, if Porsche wish to just deal with this, through their OPC's, on a case by case basis and not talk to the club about it, there is not a lot we can do. The overall numbers are small and, as has been stated before, if the issue had just been fixed under warranty we would all have moved on. As a club, our priority is to look after and support its members. Every case we have come across has received that support and has been, or is currently being, successfully dealt with.

As Dave has pointed out, we have a number of specific issues we are continuing to chase down:
The GPF is not blocked - wrong diagnosis
The Differential Pressure sensor can be faulty giving false readings
There should be a regeneration warning which comes on before it gets to a CEL. This system is inoperable.
Numerous examples of appalling service, mis-diagnosis and, potentially, overcharging
Claiming that the GPF is a service item when it is not referred to in any service schedule, check, or the handbook.
Producing (VAL) reports which clearly dont make sense.
Claiming that the car is fit for purpose whilst saying that there are types of driving that cause the GPF to get blocked
Being unable to conduct basic tests, such as AOS function, exhaust back pressure etc. which are cheap to do and would either corroborate or contradict readings.

Remember, we are dealing with Porsche OPC's here who can only evaluate what shows up on the car dashboard, PIWIS tester and diagnostic system, usually by changing out successive bits until the warning light stays out after the reset. But I feel sorry for the OPC's as they can only work as instructed by Porsche. However that does not excuse the way some OPC's seem to treat their customers.

We are trying hard to bring this to a conclusion.

John