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I am considering a 2009 Cayman S PDK with about 62k miles on the clock. The owner said that the car is suffering from a pressure sensor issue with its PDK and he managed to find an independent garage to fix it (so avoiding the usual Porsche bid to have you replace the entire PDK). What do you all think? Is this a common issue with PDKs and even if the sensor is replaced would there have been damage already done to the gearbox? Do these sensor issues tend to resurface after a while?
I'm concerned because from what I could gather people tend to say that the PDK is bulletproof and lasts up to 150k miles or more.. so I wonder if this is one of the rare cases that suggests a defect in this particular gearbox..
Thanks all!
Agree with Rfjohnson, get the specific code along with the text description provided by high end scanners like a PIWIS or Durametric. The reason you need the text is that many codes have multiple subcategories that are variations that provide specific context. Where there any symptoms prior to the fault?
Pressure sensor failures are rare but not unheard of, I can only think of a couple of instances here since we started this thread. I doubt it would cause transmission problems unless there was a long history of poor shifting prior to the fault. Usually these types of sensors just suddenly fail. Once that happens the TCU sees the out of scale value, throws a fault, and locks out the transmission. No long term harm.
HOWEVER, you need to be absolutely sure it actually is the pressure sensor!! Although the parts are not expensive, there is a lot of labor involved as it requires dropping the transmission and pulling off the clutch. We've seen way to many instances of shops claiming to know what they are doing, when they are just throwing parts at it. It used to be that few shops would touch the PDK. Now due to this thread and other info, many shops are claiming they can do the work when they really don't know what they are doing. You don't want to pay for their on the job training.
If a solenoid is failing, it could look like a pressure sensor failure (e.g. reading low pressure) when the sensor is actually fine. Although not as likely, it could be a wiring or TCU failure that is masquerading as a pressure sensor failure. This is why you need to know the exact code. Also, you can use a PIWIS to stripchart the pressure sensor outputs and compare the two sensors to each other. Even easier, you can simply Ohm out the pressure sensor using a multimeter. Although not as clear-cut, the nice thing is that there are two of them so you have a control for comparison.
Be smart, do your homework, and think this thing through. It may be a great deal if you get a good price on the car, are sure it's the pressure sensor, and can DIY or get a reasonable replacement cost. If you are not savvy and simply trusting others, this could easily turn into a $10k nightmare.
EDIT: BTW, why does the current owner think it's a pressure sensor failure?
We haven't seen damage from the position (assume that's what you meant?) sensor issue as it renders the car pretty much undriveable at that point due to not shifting. The only concern would be some of the other issues that could pop up, but your chances of that didn't increase from the work that was already done. 62k miles should still net you a lot of life left in the PDK if you aren't tracking the car.
Originally Posted by LLP
Hi everyone,
I am considering a 2009 Cayman S PDK with about 62k miles on the clock. The owner said that the car is suffering from a pressure sensor issue with its PDK and he managed to find an independent garage to fix it (so avoiding the usual Porsche bid to have you replace the entire PDK). What do you all think? Is this a common issue with PDKs and even if the sensor is replaced would there have been damage already done to the gearbox? Do these sensor issues tend to resurface after a while?
I'm concerned because from what I could gather people tend to say that the PDK is bulletproof and lasts up to 150k miles or more.. so I wonder if this is one of the rare cases that suggests a defect in this particular gearbox..
Thanks all!
__________________ Todd Lamb
Atlanta Speedwerks www.ATLspeedwerks.com
Porsche repairs, servicing, and upgrades / Certified IMS installer / PDK repair experts
Over 150 PDK's repaired and counting: https://youtu.be/m54P_zisEcI
We haven't seen damage from the position (assume that's what you meant?) sensor issue as it renders the car pretty much undriveable at that point due to not shifting. The only concern would be some of the other issues that could pop up, but your chances of that didn't increase from the work that was already done. 62k miles should still net you a lot of life left in the PDK if you aren't tracking the car.
Yeah, he said pressure sensor so my response was directed at that, and we have seen a few of them fail. If he actually meant a distance sensor it would make more sense. @LLP can you clarify? Is it the pressure sensor or the distance (position) sensor?
@LLP (wherever he went), brings up an obvious upside to this dilemma. I'm sure there are deals out there where the PDK owner fully believes that his car is a boat anchor and needs a $25k transmission. As a shop it's our job to educate them if they contact us. However, shrewd car sharks would most likely not volunteer that as they try to buy a broken car, but codes are mandatory to assess risk.
Hello everyone. Last year my 991.1 Carrera got stuck due to a malfunction of the PDK distance sensor. From there, I gathered information, imported used sensors from China, made my own case puller, made tools for assembling the case, and managed to complete the repair. But the tragedy happened again. About half a year after the repair was completed, the failure of the distance sensor recurred. Once again, I decided to repair it and bought a distance sensor from t-design, which I learned from Renlist. The last repair went well (although I had a lot of trouble ...) but this time the main shaft doesn't press into the bearings of the case. There is play in the thrust direction on the main shaft, which is press-fitted into the bearing and the position is determined by the snap ring, but the groove of the snap ring cannot be seen just by closing the case. I used the tool that was used in the last repair to pull and press fit the main shaft, but I couldn't see the groove in the snap ring. I tried to open the case again and reassemble it, but the puller also broke, and further work could cause further damage. So, I'd like to assemble it without attaching the snap ring as it is, but do you think there is a problem? In my opinion, the snap ring is just for positioning, and I think that the main shaft closed by the case and held by the bearing will not play.
Hello everyone. Last year my 991.1 Carrera got stuck due to a malfunction of the PDK distance sensor. From there, I gathered information, imported used sensors from China, made my own case puller, made tools for assembling the case, and managed to complete the repair. But the tragedy happened again. About half a year after the repair was completed, the failure of the distance sensor recurred. Once again, I decided to repair it and bought a distance sensor from t-design, which I learned from Renlist. The last repair went well (although I had a lot of trouble ...) but this time the main shaft doesn't press into the bearings of the case. There is play in the thrust direction on the main shaft, which is press-fitted into the bearing and the position is determined by the snap ring, but the groove of the snap ring cannot be seen just by closing the case. I used the tool that pulled and press-fitted the main shaft that I used in my last repair, but I couldn't pull it up and I couldn't see the groove in the snap ring. I tried to open the case again and reassemble it, but the puller also broke, and further work could cause further damage. So, I'd like to assemble it without attaching the snap ring as it is, but do you think there is a problem? In my opinion, the snap ring is just for positioning, and I think that the main shaft closed by the case and held by the bearing will not play.
So much information here!
Anyone know from all this research if the 981 and 982 PDK boxes are mechanically the same or similar? Could a 982 box be controlled correctly with a 981 TCU?
So much information here!
Anyone know from all this research if the 981 and 982 PDK boxes are mechanically the same or similar? Could a 982 box be controlled correctly with a 981 TCU?
9x7.2 (987.2 and 997.2) and 9x1.1 are mechanically very similar. the 9x1.2 introduced a new 8-speed PDK that is significantly different from the earlier units. Not positive how it compares to the 9x2 PDK but I think it's comparable.
Hello everyone. Last year my 991.1 Carrera got stuck due to a malfunction of the PDK distance sensor. From there, I gathered information, imported used sensors from China, made my own case puller, made tools for assembling the case, and managed to complete the repair. But the tragedy happened again. About half a year after the repair was completed, the failure of the distance sensor recurred. Once again, I decided to repair it and bought a distance sensor from t-design, which I learned from Renlist. The last repair went well (although I had a lot of trouble ...) but this time the main shaft doesn't press into the bearings of the case. There is play in the thrust direction on the main shaft, which is press-fitted into the bearing and the position is determined by the snap ring, but the groove of the snap ring cannot be seen just by closing the case. I used the tool that pulled and press-fitted the main shaft that I used in my last repair, but I couldn't pull it up and I couldn't see the groove in the snap ring. I tried to open the case again and reassemble it, but the puller also broke, and further work could cause further damage. So, I'd like to assemble it without attaching the snap ring as it is, but do you think there is a problem? In my opinion, the snap ring is just for positioning, and I think that the main shaft closed by the case and held by the bearing will not play.
I'll let others comment on the suitability of the omitting the snap ring though it doesn't sound like a good idea to me. We did find a replacement for that main shaft bearing and the PN is somewhere in the comments here. If you find you need to replace it let us know and we'll track down the PN.
Hello everyone. I finally made it back to the track last week VIR!
Happy to report the transmission had no problems. Driven in 30 minute intervals for a total of 4 fours.
Review my previouse comments early in the thread for my PDKs issues.
I added the center coolant radiator and a LN engineering pan/cover to the PDK fluid side of the transmission. New PDK pan increased fluid requirements by about 0,5 liter and seemed to dissipate heat better since its metal not plastic. But, I have no imperical data to back that up just the fact it did not throw the overheat codes from the gear side of the transmission.
Thanks again PV997 for all your help.
Dave
Hi. Have anyone have installed a 2013 transmission on a 2009 cayman? I know there are some differences between the two but is it possible make it work? If if is what I have to change? Thanks in advance. Have a nice day
Hi. Have anyone have installed a 2013 transmission on a 2009 cayman? I know there are some differences between the two but is it possible make it work? If if is what I have to change? Thanks in advance. Have a nice day
I've never heard of it being done but it seems like it wouldn't be impossible.
The 987.2 and 991.2 PDKs are nearly identical but with a few key differences. in 2013 Porsche added a gear oil pump and cooler to the PDK, along with adding the option for a locking differential. All of these added some additional control circuitry which you wouldn't be able to operate in a 2009 car. That being said, you may be able to just disconnect or bypass them them and use the 2013 transmission as the functional equivalent of a 2009 PDK.
My biggest concern would be that some changes were made to the clutch assembly allegedly to strengthen it, including some dimensional changes of the plates. I don't know how compatible this would be with a 2009 transmission control unit (TCU) or if it might lead to clutch calibration or shifting issues. I suppose you could upgrade the TCU to 2013 programming, but then there then may be compatibility issues with the TCU interface to the 2009 ECU.
If you got a great deal on a 2013 PDK and were willing to spend some time troubleshooting a project then it might be worthwhile. Otherwise I'd stick with a unit from a 987.2.
I read thru most of the 57 pages and didn't see any mention of the ?recent? price drop in replacement PDK transmissions from Porsche. The price for a 9G1-300-031-FX (991.1 Turbo S PDK with LSD) as of May 2022 is ~$11,300. And after you get your core refund the price is ~$4,300 USD ($11,300 for the PDK minus $7000 core refund).
Now even a price drop of $4,021.95 (26.30% off the original $15,321.71)will never justify replacing an entire PDK for a $100 part failing, but a rebuilt/new PDK direct from Porsche for around $5500 installed (~$4300 + ~$1200 indy labor guess) is way more attractive than the ~$20k in the "before" times.
Any others owners have a similar feeling as me that price point is now low enough to justify going all in for a new PDK and not looking back if it ever was needed? I know I sleep better knowing, in theory, if i needed one, a new PDK is actually "affordable".
@sonic991 not sure if the math works the way you describe. First, the core charge is ADDED to the price listed. You pay $18268.71 then get the $6968.95 core refund. This nets a replacement cost of $11299.76 (plus tax) versus your ~$4300 (plus tax). Also, not sure about $1200 indy labor. Sounds low.
Good to keep an eye on what Porsche is doing tho. I would love to believe the mothership is taking a kinder approach toward standing by the ZF units…but I am not optimistic.
What if the PDK is rebuilt using the same failure prone parts? Is it possible you're better off keeping your trans and having the bad parts changed with updated ones?
Also, a PDK trans for my car, a 2012 GTS is still over $19K plus install
05-01-2022, 12:38 PM
