PDK problems - Page 1 - Boxster/Cayman - PistonHeads UK

Not that long ago a chap on here detailed his failed PDK journey, Iike a few others with PDK Porsches it gave me pause to think these boxes are not anything like bullet proof. Last Friday I was out for a drive on my usual route in my 718S Cayman and the ' Possible R fault, driving permitted ' fault code appeared. I pulled over where I could and restarted but it reappeared a few miles later. I managed to get home after another restart and started to do some digging. I checked the voltage on the battery and it was reading low ( 12V ). It seemed a possibility given my previous experience with modern cars and low battery voltage. I booked the car in to ATS for a battery replacement. Turned out it was the original dated 2016. The new battery was recoded but his OBD reader didn't find the faulty transmission codes so I took it to a local German car specialist who found them and removed them at which point the dash warnings disappeared. However on my journey home I noticed a slight hesitation on a shift and this is something I noticed on the previous Friday shortly before it threw up fault codes. Later same day I took it for another drive and sure enough a brief hesitation before the same fault re-appeared, also the loss of odd gears. Re-starting removed the fault but it's looking like the dreaded distance sensor fault. Researching online shows this to be a common failure on PDK transmissions. Ive had a very slight leak from the bell housing which I assumed was engine oil but it could be PDK fluid. I had this changed without filter about 6K ago. The car has done 80K. I'm ringing Austrin Gearbox Specialists today - they do PDK's, I spoke to them briefly before the battery was changed so I'll have to book it in to read codes and get an idea of the work needed. Along with the loose blanking plug issues I had when I got the car at 70K ( major oil leak ), I'm unimpressed with modern Porsche reliability. Porsche obviously know about the transmission issues as I believe the latest PDK's have been changed on recent cars for a later iteration. However you can't buy the distance sensors from OPC, or any other PDK internals.

Sorry to hear this OP. If the PDK box has a leak or suspected one then this could be worth checking first before going down the whole replacement route. Unfortunately Porsche don't supply components for the box. The only option is a straight swap however I do believe it is possible to 'exchange' the unit which brings the cost down. Good luck

hooch500 said: Not that long ago a chap on here detailed his failed PDK journey, Iike a few others with PDK Porsches it gave me pause to think these boxes are not anything like bullet proof This may be the thread you are referring to.... https://www.pistonheads.com/gassing/topic.asp?h=0&...

A technician once told me not to do an oil change on a higher mileage auto gearbox, as it can cause problems. No idea if that was good advice, or not. Please keep us updated.

Yes will post updates it’s going in tomorrow so we will see

Update. Austrin Gearbox Specialists have got the car now. They have read codes and assure me it’s fixable as they did another with same codes. They reckon 3.5 k plus vat. However if I wanted to future proof it by fitting replacement distance sensors then it’s another 2k.

Update. Turning into a bit of a nightmare. They diagnosed pressure pad sensor issue. Box was removed and some parts were replaced which were not especially expensive, including new PDK filter etc and a seal which was leaking. Was given option to replace distance sensor to future proof it, but I thought it would be unlikely to happen again in the time I’m likely to have the car. Anyway parts and labour £ 4200. However went for a drive today and to my dismay exact same fault came up. Identical symptoms. Done less than 100 miles. To be continued..

Sorry to hear what a pain. Is why some pay so much for extended warranty and Porsche servicing I guess.

Ironically enough I went for a PDK as there were so few manuals, of which most had a few miles and non of which had replacement clutches. So far I could have replaced clutch 3 times given outlay. Anyway let’s see what Austrins do as the issue lies somewhere else.

hooch500 said: Update. Turning into a bit of a nightmare. They diagnosed pressure pad sensor issue. Box was removed and some parts were replaced which were not especially expensive, including new PDK filter etc and a seal which was leaking. Was given option to replace distance sensor to future proof it, but I thought it would be unlikely to happen again in the time I m likely to have the car. Anyway parts and labour £ 4200. However went for a drive today and to my dismay exact same fault came up. Identical symptoms. Done less than 100 miles. To be continued.. That's really bad, time for them to step up and resolve the issue without making out it was some other issue and covering their mistake with more money from you.

Early-bird said: Sorry to hear what a pain. Is why some pay so much for extended warranty and Porsche servicing I guess. Exactly, but what happens when OPC will not warranty cars after 13 years at all, (irrespective of full OPC SVCE History & Warranty), so anything 2013 at youngest is unable to have OPC Warranty NOW, and that 2015 mint 981/991 is going to be in the same position in two years. What's it going to do to residuals going forward unless a reliable cost efficient fix can be found. For example:- Tom Hartley Jr has a 2015 981 GTS Boxster for sale at £59,500 https://www.tomhartleyjnr.com/car/stock/2015/porsc... Very low miles, looks lovely, (Overpriced IMO) but who's going to take a chance on sinking this sort of money into a car that could need a new transmission at circu £20,000, which is 33% of the purchase price and in two years you won't be able to put an OPC warranty on it under any circumstances even though Porsche have serviced it entirely from new...................... Ticking time bomb for loads of cars out there

Further updates on this. I took the car to a local German car specialist who read the code before I took it back to transmission specialist. It was a different code to the previous one which related to the pressure sensors which were replaced. Although the net effect was identical in so much as the warning of Possible R fault driving possible it appears this fault relates to the clutch selection ( P17BC ), which likely could mean the valve body mechatronics. After I restarted it it went away but given my experience first time I was sure it would return. The 30 mile drive to garage was fine. I interrogated Chat GBT, which turned out to be a good idea. The information I have received is incredibly valuable and the advice excellent. I would urge anyone to use it with something of this nature where information is hard to find. The garage pointed in the same direction. Anyway I ve decided to pick it up and drive it further to try and replicate the same thing. ChatGBT even gave a structured plan for the drive. First they need to resolve a coolant leak which definitely wasn t present before. There s a slim chance the issue was due to a glitch after replacement PDK fluids and reset. It s likely there is an underlying problem though and the valve body was the ROOT of it. It probably should have been checked for pressure values when the box was out. The only good news is that valve bodies ( complete), can be done in situ on a ramp. They aren t cheap and although there are Chinese clones available it s not a chance I m willing to take. Hindsight is a wonderful thing, there aren t many used boxes here in UK but plenty in Germany as you would imagine. 718 boxes are quite reasonable especially compared to 911 PDK s. I ve seen a low mileage box ( looks it too ) for £3500.00. Had I known I probably would ve taken the chance. I m looking out for a used valve body so let s see what happens. Edited by hooch500 on Saturday 4th April 09:28

Spevs said: Early-bird said: Sorry to hear what a pain. Is why some pay so much for extended warranty and Porsche servicing I guess. Exactly, but what happens when OPC will not warranty cars after 13 years at all, (irrespective of full OPC SVCE History & Warranty), so anything 2013 at youngest is unable to have OPC Warranty NOW, and that 2015 mint 981/991 is going to be in the same position in two years. What's it going to do to residuals going forward unless a reliable cost efficient fix can be found. For example:- Tom Hartley Jr has a 2015 981 GTS Boxster for sale at £59,500 https://www.tomhartleyjnr.com/car/stock/2015/porsc... Very low miles, looks lovely, (Overpriced IMO) but who's going to take a chance on sinking this sort of money into a car that could need a new transmission at circu £20,000, which is 33% of the purchase price and in two years you won't be able to put an OPC warranty on it under any circumstances even though Porsche have serviced it entirely from new...................... Ticking time bomb for loads of cars out there Is 15 years or 125k miles (the warranty limit). https://www.porsche.com/uk/accessoriesandservice/p... Or were you just trying to talk the price down with Hartley?