Cayman 718 GPF Failure

[Jamoran]

Brilliant ! Absolutely fantastic for the owners but especially Dave, Jeff and others that kept this alive. I followed this for months now, could not contribute much technically, and was at times astounded that Porsche could let this rumble on.
Again well done and many an owner will sleep a bit better.
Jim

 

[Cyclemotor1958]

Thanks Jim,

Without Prejudice

We have still some work to do, hopefully this week we will finally have the proof that the lack of a soot loading light on the cars we have seen is definitely contributing to the premature failure of these GPF filters.

Kind regards
Dave

 

[Cyclemotor1958]

Hi Guys & Girls

Without Prejudice

Well it's been a busy week again, we had two objectives this week to confirm the following.

1. Confirm the GPF filters are not blocked, even though the oil ash load measured is reading 100%.

2. Confirm that when a soot over load code is in the engine management system, the particulate warning light does not come on.

Let's start with no1

Our Cayman 718 2.0 2019 car went into the workshop today with the engine light on and the message (permitted to drive on the dash).

We checked for diagnostic codes and found the usual P242F, ( ash load to high), it was at 100%.

We removed the engine cover, located the differential pressure sensor, removed the rubber pipe from the GPF filter into the input side of the sensor and read the pressure.

The pressure was 0.02 psi, the sensor reading on the GPF diagnostic report was 1.41 hpa.
These pressures are the same basically very little measured pressure at all.

So why do we have a measured K231 value of 100%, when in fact we have very little pressure from the sensor.

Remember all the cars we have looked at show very low differential pressure sensor readings compared to high oil / ash readings.

The question I would like to ash Porsche Technical is, how is this measured value calculated.

Because it's clearly wrong, and the Dealers are replacing these GPF filters for nothing.

I have said many times on this forum that the exhaust back pressure needs to be checked first.

We do know that the when the dealers are presented with a 100% oil ash reading.
They will try to regenerate the filter, even though its blocked with Ash, to try and clear the code.

If this doesn't work, Porsche Technical instruct them to fit a new filter.

You can draw your own conclusions on this.

Let's look at no2.

We have another Cayman 718 2.0 2019 car still in a workshop with a soot overload code in the engine management system.
We have never seen this code before and the code is P2463, (particulate filter-soot load high).
And also another code 26740 (particulate filter-regeneration required).
The warning light on the dashboard was the same warning we get for the oil ash at 100%.
This information confirms without a shadow of doubt that this car does not have the handbook described amber warning particulate light displayed on its dashboard.

Now bearing in mind we have never seen the amber particulate filter warning light working on any of our vehicles suggests its not working as intended.

I have put together some information on a photo to confirm the following.

1. Photo of the warning light displayed on the dashboard.

2. The Porsche PWIS diagnostic Fault code P2463 with description

3. The code in the instruments 26740 suggesting particulate filter needs a regeneration.

4. The PWIS GPF report, showing high soot load figures that we have never seen before.
Also again a very low differential pressure sensor reading.
We checked for exhaust back pressure and found none at all.

5. Documented information from VW with regards to a Tiguan 1.4 petrol that was built in 2017, and was an early GPF fitted vehicle.
It shows in detail the dashboard display covering the stages of GPF emission control that was created for these cars.

6. Our Porsche drivers handbook showing the amber particulate soot warning light and further instructions.

To summarise.

The exhausts are not blocked with ash, after all they should last beyond 100k and above.

The soot driver regeneration warning light doesn't seem to work on our cars and it should do.

This emission system has its problems, measured and calculated values that don't make any sense at all.

These cars are being sold, and the owners of these cars, are still not being told about the emission device fitted to their cars at the point of sale.

Why not, unless we have something to hide, remember its the manufacturers responsibility to build a car fit for purpose.

How long is this going to go on.

Dave.

 

[Cyclemotor1958]

Hi Guys & Girls
Some good news at last,

Just received a message from one of our drivers with a faulty GPF.
It's finally been authorised, by Porsche under warranty.
Big thanks to the Dealer and Porsche.
Dave

 

[Wrightrubber]

Another good result Dave.
If I understand your analysis correctly, these filters can't be blocked and it proves conclusively that the particulate filter light to tell the driver to perform a regeneration, as per the handbook, DOES NOT WORK!!!
Mark

 

[Oldbiddy]

Hi Guys & Girls
Some good news at last,

Just received a message from one of our drivers with a faulty GPF.
It's finally been authorised, by Porsche under warranty.
Big thanks to the Dealer and Porsche.
Dave

That's excellent news and a big thumbs up for you for all the investigative work you have done on this.

However I cannot get my head around this. If the filters are likely not blocked as you point put in your previous post, then changing the OPF may achieve nothing as it is not addressing the root cause of the problem. I believe you have seen examples of filters blocking again soon after they were replaced. So why are Porsche doing this?

Or am I missing something (entirely possible!)

 

[michaeldowgill]

Great work Dave. Maybe now Porsche will realise they have some work to do to make sure their loyal customers can rely on them to sort out the faulty PPF system, as it's not fit for purpose.

 

[Motorhead]

That's excellent news and a big thumbs up for you for all the investigative work you have done on this.

However I cannot get my head around this. If the filters are likely not blocked as you point put in your previous post, then changing the OPF may achieve nothing as it is not addressing the root cause of the problem. I believe you have seen examples of filters blocking again soon after they were replaced. So why are Porsche doing this?

Or am I missing something (entirely possible!)

If the dealers are basing their assessment of GPF failure on readings from a faulty differential pressure sensor it’s quite possible that the filter isn’t blocked fully, and therefore is being replaced unnecessarily. Coupled with that the DPS will still be providing erroneous data!

Surely the most sensible approach should be to replace the [relatively cheap?] DPS before resorting to the replacement of the very expensive GPF unit?

Jeff

 

[Paul-718gts]

If the dealers are basing their assessment of GPF failure on readings from a faulty differential pressure sensor it’s quite possible that the filter isn’t blocked fully, and therefore is being replaced unnecessarily. Coupled with that the DPS will still be providing erroneous data!

Surely the most sensible approach should be to replace the [relatively cheap?] DPS before resorting to the replacement of the very expensive GPF unit?

Jeff

Hi Guys & Girls
Some good news at last,

Just received a message from one of our drivers with a faulty GPF.
It's finally been authorised, by Porsche under warranty.
Big thanks to the Dealer and Porsche.
Dave

Sorry to contradict you Dave but is it good news as we all know swapping out this part is not finding the root cause even if it’s being done FOC and it’s daylight robbery if the owner has had to pay.. should we be thanking Porsche for fudging something that even by changing parts isn’t putting things right.

For those of you that don’t know Dave and I have been talking daily since June/July on this issue following a GPF failure on my car.

As far a I am aware my car is the only one that has had both the DPS changed along with the GPF and following a recent VAL test I can 100% confirm swapping parts is not the answer.
We have tried to engage the owners club for support and advice and to be honest the results to date have been non existent.
Once I get some time over the weekend I will post a summary of my journey along with VAL figures at each stage of the journey both pre and post parts being changed.

I will however like to personally thank Dave for his support during this process and our journey to conclude this scandal isn’t over…

More to follow.

 

[Motorhead]

Paul,

I wasn’t aware that the dealer had changed both the GPF and DPS on your car, so clearly the issue hasn’t been resolved, and it’ll be interesting to read your journey in full.

Quite understandably you’re frustrated that you’re not getting anywhere with Porsche UK or the Club, and I think it’s time to take individual action [I think it highly unlikely that Porsche will acknowledge a problem publicly]. I recall that some time ago Dan suggested that you contact Auto Express [he even gave you some specific contacts], having had some previous success there himself. Have you followed this up, or have you contacted the Motoring Ombudsman?

Jeff

 

[Paul-718gts]

Paul,

I wasn’t aware that the dealer had changed both the GPF and DPS on your car, so clearly the issue hasn’t been resolved, and it’ll be interesting to read your journey in full.

Quite understandably you’re frustrated that you’re not getting anywhere with Porsche UK or the Club, and I think it’s time to take individual action [I think it highly unlikely that Porsche will acknowledge a problem publicly]. I recall that some time ago Dan suggested that you contact Auto Express [he even gave you some specific contacts], having had some previous success there himself. Have you followed this up, or have you contacted the Motoring Ombudsman?

Jeff

Hi Jeff,

I haven’t yet as I was awaiting the results of the 1st VAL test,post the warranty work that was completed.

 

[Scrounger]

As I've mentioned before, the only way to get Porsche de involved and look into it more closely is to go to the press.

 

[Cyclemotor1958]

Hi Guys & Girls

Without Prejudice

Sorry its me again,

The trouble with posting out lots of technical information is you always forget something that needs to be said, and remember it later.

Durring last weeks investigation on one of our cars we could not find on the Porsche PWIS diagnostic tester the function to carry out the adaptation when replacing a new differential pressure sensor.

The sensor is a VW part, and we checked with our local VW garage, and they confirmed that they always adapt a new sensor when it's replaced.

This adaptation clears historical data in the ECU, and starts afresh with the new sensor.

This is really important on this car, as it seems this sensor is the only sensor that measures actual soot values as seen on the GPF diagnostic report.

Everything else is either measured or calculated.

The measured soot value K221 comes from the differential pressure sensor readings.

And the calculated soot value K211 comes from the ECU internal model, based on time and how much load is on the engine.

It's the calculated K211 that triggers a regeneration of the GPF filter.

Looking back at historical GPF data from lots of our cars, it not uncommon to see 0.00 values in both calculated and measured soot readings, when the cars are showing a oil ash level of 100%.

No wonder these cars are not working correctly.

The next issue is how do you reprogram the engine ECU after fitting a new GPF filter.
Again we couldn't find anything on the Porsche PWIS system to help us.

This is not right, the engine ECU needs this information to continue providing correct data to run the emission system correctly.

We suspect that there could be an issue with communication between the ECU and the other sensors within the emission control.

If we are wrong about this, then can anybody from Porsche Technical or the dealers contact us and explain please.

We have 100 % proof that these filters are not blocked when the system is reading 100% oil ash values, so why can't the oil ash figures be reset again.

This next week we will be looking at this in more detail, and hopefully, we will find some answers.

We need Porsche Technical to look more closely at the software on these cars, bearing in mind all the work we have carried out so far.

Dave

 

[Motorhead]

That’s all very concerning Dave. As a general observation you have to wonder how much technical resource is now being allocated to 718 issues since I would imagine that the majority of the current development effort is concentrated on the electric Cayman and Boxster replacements.

Jeff

 

[Scrounger]

On that Jeff, rumours are that the Cayster EV has been shelved. Not sure how true it is but thats for another thread.

 

[Motorhead]

I’ve not seen that Dan! If true it would be a very late call given that at this advanced stage all the tooling will have been made and the production line prepared, but who knows with the current state of the EV market and with Porsche profits falling?

Jeff

 

[Cyclemotor1958]

Hi Guys & Girls
Without Prejudice

Well another driver of a Cayman 718 2019 car contacted me again today.
Usual oil ash over load.

I know I've said this before but we have two issues that need sorting ASAP.

1. We need the engine management system on these cars to be able to re set the oil ash load to 0%.
If the engine light is on, and the code P242F is present, and the exhaust is not blocked, why can we not reset this value.

2. The soot warning light system needs to work on these cars, as detailed in the drivers manual. Surely a software update could be created to fix this issue.

If you type this into YouTube you will see how easy this could be.

VCDS-DPF (FAP)-reset value to 0%

Dave.

 

[Paul-718gts]

Hi Guys & Girls
Without Prejudice

Well another driver of a Cayman 718 2019 car contacted me again today.
Usual oil ash over load.

I know I've said this before but we have two issues that need sorting ASAP.

1. We need the engine management system on these cars to be able to re set the oil ash load to 0%.
If the engine light is on, and the code P242F is present, and the exhaust is not blocked, why can we not reset this value.

2. The soot warning light system needs to work on these cars, as detailed in the drivers manual. Surely a software update could be created to fix this issue.

If you type this into YouTube you will see how easy this could be.

VCDS-DPF (FAP)-reset value to 0%

Dave.

Hi Dave,
Is that VAG software ? If so they already have the method within the group so no need to re-invent the wheel

 

[Cyclemotor1958]

Hi Paul,
Yes it's VAG software,

I have another car going in to a Porsche independent garage tomorrow to check the exhaust back pressure.

Will keep you all updated
Dave

 

[Sp1ke]

Sorry to hear of this fiasco, but kudos for your collective tenacity in pursuing this.

I’m considering the purchase of a 981 or 718 in the coming months, so I’m curious to know if this GPF issue affects all 718’s with a GPF including the 4,0 models?