Hi. I'm new to this forum and looking to contribute back to community that helped me fix my car. My 997.2S had a distance sensor failure at 114k. A shop quoted around 20K to replace the transmission but I was able to use the info a man named Jeff Richardson has been sharing to fix it myself.
I tried to post about it on Rennelist and my post was deleted shortly after I posted it, along with another thread I'd started with the info I was trying to share with the community. It really bugged me, because it seemed like my posts were purposely removed in order to send business to those that pay as sponsors on that site. Very disappointing to see. So that is how I find myself here, just looking to share my experience. If a moderator see's a more fitting place to put this info, please move it so people can find it!
The problem:
Car would not drive forward or backwards, the CEL was on, and the "transmission emergency run" message was displayed. Among the codes was P1734, a death certificate for the distance sensor.
Using Piwis I was able to see shift rod position for gears R-2 was at -11.492mm, when it should read something like +8mm, validating the P1734 code.
Sensors:
I reached out to both T-Design and Jeff Richardson (via his youtube channel) about their respective sensors. They both got back to me quickly and it was clear TDesign is targeting shops, and Jeff is a solution for the DIYer. I say this because Tdesign has you soldering wires to your existing harness, and emphasizes that if something goes wrong during calibration, you’re on your own. The website for Tdesign mentions it is not a DIY type job. Jeff, while just 1 person, had lots of info out there on how to do the work, and I just got the feeling that if something went wrong during the work he would take the time to try and help me (as can be seen by his immense contribution to the forums and his youtube vids).
Solution: I reached out to Jeff because in one of his video's he talks about a JUMPS sensor and I wanted to know more about it. It turns out the sensor he makes is actually prewired, and includes a new speed sensor, circular pinned connector with orings, and the distance sensor itself is pre-compensated for the specific transmission you have. You pull it out of the package, remove the old sensors, and install these ones.
Also, on cost, the TDesign replacement sensor cost almost 2x as much as the JUMPS solution. All this to say, I went with the JUMPS sensor, and I would certainly recommend it after doing so.
The work:
These are my summarized notes for someone heading into this. Definitely use the guides Jeff has on youtube, then check my notes for 997.2 specific info.
For me, I do stuff like this all the time. I have other cars with problematic DCT’s and enjoy working on them. I have built engines, can fabricate well and am generally excited to solve challenges like this. I’m a development engineer by day and hillbilly engineer by night. So I’d rate the wrenching of this a 4/10 difficulty, the software side a 5/10. Replacing my coolant reservoir was a 1/10 for reference.
Hardware: I did the job with my car in my driveway, made the tools myself, and had help from a really nice guy known on these forums as PV997. Jeff Richardson actually connected us, after learning PV997 and I lived near each other, and PV997 was kind enough to come by and get his hands dirty to see for himself the level of difficulty it was to do this job with the trans in the car.
I only lifted the back of the car, and lifted it as high as my jack would go. If you had a proper lift the extra space you gain would make the work easier and less annoying. But I’m lazy and tend to have a laugh now cry later mentality.
The work is well documented already in Jeff's boxster/cayman videos. For 997.2s the main items that stood out to me:
-I didn’t disconnect anything from the engine side. I didn’t even open the engine hatch. I just removed the under trays, then removed the braces holding the front of the transmission. Just take the 2 studs out from the arched upper trans mount and it comes right out.
-Before you shut the car off for this, leave in neutral. Under the car, pop the shift mech off and then you can put the shifter in park and take the key out, while the trans stays in neutral.
-I let it all hang down as far as it could, it just rested on the aluminum crossmember that is part of the subframe. I removed the tie brace.
-I removed the trans oil cooler, I pulled the hard lines from the trans side and not the cooler side. It will leak indefinitely. This is the hydraulic clutch oil (Pentosin FFL3), not gear oil. I changed both gear and hydraulic oil so I didn’t care that it leaked out.
-The puller was like all the others you see drawn. I made mine and then had to kind of shorten the puller studs to fit the space under the car. The 911 holes are square, and closer together. The boxster cayman holes are slightly further down and a little more inboard. The dimensions are in one of the videos Jeff has.
I think you can buy a PDK puller kit off Amazon and ebay that has all this stuff for under $200. Hopefully someone can verify it has the large metric threads for pressing/pulling on the shafts.
-I used a 36mm socket and welded 4x 0.25” woodruff key’s on the perimeter to fit the slots of the keyed nut on the lower shaft of the trans. I ground a punch drift flat and hammered that in between the deformed parts of the nut to spread it. It took a lot of force to break the nut loose. The top shaft was just a circlip.
I threaded in the large metric bolts into the shafts and then case puller studs and “pulled” the case against the large bolts in the shafts. The case moved about ¼” before the telltale pop was heard of the shafts moving in the bearing races. By the way, prepare for a gear oil bath around here, even if you try to drain it all.
-The sensor swap was the easiest part. I think anyone who turns a wrench can do this by just looking at it. After I swapped sensors, I checked piwis before reassy to see, and sure enough the R-2 shift fork was reading +8.062mm instead of -11.xxx. Yay! One note, I have worked on the DCT used in the Mitsubishi Evolution, and the magnets on the shift forks can accumulate a lot of magnetic dust, supposedly affecting the quality of the readings by the distance sensor. Wivestale? Idk but I spent 10 mins cleaning those really really fine ferrous particles stuck to all the shift fork magnets and slept better that night.
-On reassy the case lined up really nicely, but pressing it on was probably the most annoying part of the job. I had an idea of how I wanted to press it using my large metric bolts and nuts, but in reality, I ended up having a hard time with the top shaft. There is very little space to hold and turn these large fasteners. My alter ego came out and used an impact. I just alternated between top and bottom until I felt them bottom out. At this point there was still a 1/16” gap between the cases. This was just the freeplay in the bearings/shafts which was taken up when I reinstalled the perimeter case bolts.
-The circlip went back on seemingly flush or very close to, and the nut (as tight as I could get it with ½” ratchet) landed in the exact same position (you can tell by the alignment of the detents). This made me feel good. I did use a lot of Loctite on the nut, just in case.
Software:
Here is the part that almost wrecked me. I have the VXDAS piwis 2 adapter and the virtual piwis 2 setup on my old computer. When I went to clear all the codes, and I had a lot because my battery had died at some point, not all of them would clear, and I could not tell which if any were actual problems. So PV997 and I took the non-calibrated car for a drive, and many of the codes cleared themselves, then the rest were able to be cleared with the engine off/ignition on. For some reason certain codes just would not clear with the engine running. Once we cleared them, they did not come back.
When we tried to calibrate, we got a message about my TCU having a firmware that was not able to be calibrated. We figured out this was due to my TCU being old, I have one of the first PDK 911’s to come to the US and the TCU was never updated. So we used piwis to flash the TCU to some newer version. After flashing, we got a TCU error P1749, which we could not figure out, the verbiage was something like “Version coding invalid” which I translated as “time to buy a new tcu, dummy” . I was worried we had flashed an incorrect version, or something. Turned out to be an easy fix. It is not well documented but if you have P1749 from your TCU, it is because the coding is not done. You just need to go into coding adaptations and code the PDK to your country.
Once I did that, I had no more faults, either DME or PDK, so I proceeded with calibration, which completed first try. I now have almost 150 miles on the car and all seems well.
I am summarizing here, but there is plenty of info out there now on this job, and if you go slow and have some experience in wrenching, I bet you can get it done. Especially if you are active on the forums, both JJrichar and PV997 are ready and willing to help, as they did with me.
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Wonderful! Jeff told me how the "other" forum had pulled his writeups there. They appear to bow to advertisers (part of the reason I'm no longer there, and a number of other people here are no longer there..) even at the expense of their members. This isn't the first time this observation was made. Here - I have almost no clue who the advertisers are since I never see the ads (good to be God..) and the home office is sometimes remiss about informing the local operations that they've added an advertiser.
It's funny how that other forum is making this forum
the resource for DIY/independent-shop PDK repair
. I guess I should thank them, but never mind.
Thanks MUCH! Please do take a few moments to introduce yourself and your 911 on our
https://www.planet-9.com/forums/new_members/
forum! We love pictures! And that Blue looks awsome..
This is nothing short of incredible.
I've been following your replacement through PV997 and Jeff, great work! For future reference, there is a written how-to for this on the other forum but I'll post it here too. I am working on updating it to be more specific for the
JUMPS sensor
, which is a superior product in all ways, and to add more detail and better pictures. In the meanwhile it is still a valid guide for this task if anybody else wants to take it on. I will also create one that is
Cayman
/
Boxster
specific as I will be doing a replacement on both a 987 and a 997 later this month.
The Chinese
PDK
tool kits you referenced are definitely worth the money, PV997 recently found one for $170 on
Amazon
but there are plenty on eBay and
AliExpress
. Make the job a lot easier. The updated guides will be based on using one of these kits.
Yeah... I've been active on many automotive forums for the last 15 years, and had not experienced the level of manipulation I encountered on Rennelist. I think that type of behavior will quickly kill the vibe. The only other threat is facebook groups. In theory it's great, but you quickly lose information, with people asking the same questions repeatedly and no good way to search for anything.
My post was pretty much the same as I wrote above. Anyways, I'm not here to whine about it, I'm here to engage a bit and hopefully pay it forward by helping other enthusiasts where I can. Thanks for the warm welcome!
I saw this same writeup, it is very helpful. I think there have been a few people who did the job but just haven't posted much about it. I believe there are also a few shops who do this job claiming the trans HAS to come out of the car to do this work, and that doesn't seem to be the case.
It seems pretty straightforward now, and hopefully as more and more people do the job, the perceived difficulty/expense will go down to what it actually is: Not that hard, like $1100-1300 for new
JUMPs sensor
, $500 for
Piwis
. Oils, maybe trans pan with filter, tool kit. So say all in $2100 in parts, 12 hours of time.
I guess certain people see the crest on the hood and get dollar signs in their eyes...
Great job!! Much more than hillbilly engineering!! Jeff is outstanding...
I guess teh real question is if you have a lift and are doing it yourself, is it easier/better to drop the transmission and work on the bench, or for this particular repair is just as well leaving it in (less disconnect and reconnect work), and open the case with it mounted in the car?
You definitely want to leave the transmission in the car for this. Removing it adds a lot of time/work and of course the risk associated with having to handle a heavy transmission on the way from and to the car.
Hello everyone, great read! I have a question for the group. I own a 2013 991.1 C4S. I received the "Possible R gear fault possible to drive on" error recently. 87,500 miles on the vehicle. I took it to a
PDK
specialty shop in Lake Forest, CA, where they determined it was a valve body problem. I then had them replace the valve body. Now the vehicle is throwing the following error codes: P1773, P1765 and A016. Do you think this is because there's a problem with the new valve body, or it's because the speed sensor needs to be replaced? I hope it's ok to ask this question here, if not I apologize, but I'm kind of at my wits end. I've already thrown $6k at this, and the thought of another $9k to replace the speed sensor is a bit disheartening.
Any help would be greatly appreciated, or if anyone knows someone in the southern CA area that would be great! It sounds like most here are much better mechanically then me. I've pulled the engine from my 75 Camaro years ago, but had help from others with way more experience. Working on a
Porsche
scares the hell out of me, especially when I read how others had to fabricate tools to complete the job. Thanks so much in advance!!!
@hillbillyengineering
was awarded our coveted "Technical Excellence Award" with this thread. I'm hoping to see more from him.. this thread was excellent in showing how a fairly competent home wrench can fix an issue that would otherwise make the vehicle worthless without factory tools, but with the support and knowledge of Planet-9 technical postings. Thanks much for the contribution.
Hey thanks! Checking back in - I did a track day at Laguna Seca two weekends ago, watching the trip counter I had 18 hours/900 miles of driving over 3 days. What a blast, you can tell the car was built for this type of enjoyment
Best time of 1:48. Everything stock on the car except my JUMPS
PDK
distance sensor which worked and is still working flawless.
