Floyd540

I don't have a dog in the PDK fight, however I do have thoughts on solder versus crimped connectors. If done truly correct, then no issue with either. There is no creep in metal on metal (wire to connector pin) so they will not loosen if proper force was applied. Soldering makes a "perfect electrical and mechanical connection if done right. What is an issue with solder is if you overdo it then excess solder will wick back up the stranded wire inside the insulation and form a hard spot . This takes away some of the flexibility in the wire length and you may not know it. This is a classic failure in soldering the bullets onto the stranded wire like in 356's. Just enough solder to fill the bullet and nothing more. Many people with the more is better philosophy will keep applying solder and the wire will become solid and rigid sometimes an inch back. This reduces the flexibility needed for vibration ,the reason for stranded wire. In time the wire will break. Do it right and it works. Either method done wrong is still wrong.

PV997

Curious if any of you guys have come across this before and can add any additional info. Over in another thread a guy noticed seepage from a plug on the side of his PDK. His worthless dealership is telling him the only way to fix it is to replace the PDK for $18k.

The white arrow show the seepage location on his 997.2 PDK (not his transmission shown but one out of the car for clarity):



Based on his description it seems to be clutch fluid and not gear oil. This show shows a cutaway of where the plug goes (white arrow). Based on this I think it's probably part of the hydraulic circuit that controls the shift rods. Has anyone removed this plug and knows what's behind it? I'm wondering if there's a check valve/metering orifice or something spring loaded behind it. We are trying to figure out of the plug can have thread sealant or something similar applied to fix the seepage. I'm concerned that if the plug is removed entirely other stuff (springs, check *****, etc.) could fall out.



Any thought or comments welcome. If this is part of the hydraulic circuit it probably requires a PIWIS to run the fill procedure after removal to purge air.

Fullyield

I recall a thread about changing PDK fluid about 6 months ago where OP mistakenly removed the plug in question thinking it was the fill hole for the new clutch fluid. I do not think anything happened when he removed it but not certain. You might try to find that thread. I think it was titled “PDK Gear Oil Change” but again…not certain. Sorry I can not br more helpful on this.

amet

I removed it while doing a PDK fluid flush and nothing went wrong… I might be able to have a closer look at the open transmission in the next few days and I’ll report back

PV997

That for the comments Fullyfield and amet, appreciate the responses. Amet - please post if you do find anything of interest on this plug. Since Porsche says you have to replace the PDK for many different types of leaks it may be worthwhile to update the main post to include a section on leak repair. That connector right below the plug can also be a leak source.

yarindadon

I have a 991 with a defective placement sensor, I ordered from t-design the sensor, and now the gear is removed from the car, I wanted to know how you built the special tool that holds the gear ⚙️ in place, maybe you have any schematics?

CarFreak427

Hi all, first time poster. Please feel free to point me in the right direction if there’s a better place to put this, I think it might be helpful.

I’m a tech at an independent shop and we recently had a 2015 Macan Turbo in with what I hear is a not-so-uncommon “PDK failure”. Car was stuck in 2nd gear going forward but thankfully also had reverse. Many transmission faults stored. Warnings in the cluster. Porsche quoted a new transmission. I replaced the valve body along with the attached TCM computer, fluid and filters. After being towed to Porsche to program the new valve body to the car, all is well and the car drives normally again. Is this something people know about? Should I start a new thread?

Thanks

Kuro Neko

Sounds like the valve body replacement fixed all issues?
With the above details, you can see the suggested breakdown and possible fixes for individual valve body diagnostics and repair?

It may not have been necessary to replace entire valve body...

docdrs

perhaps a list of the stored faults would help for your thread

PV997

Hi carfreak, success stories are always welcome, particularly after a dealer says all is lost. The whole point of this thread was to get people to stop listening to their dealer (who is either clueless or frankly dishonest) regarding the PDK and to think for themselves.

That being said, the Macan PDK is much different than the PDK discussed in the post, in fact I don't think it's even made by ZF (someone please correct me if wrong). This thread is focused specifically on the ZF 7DT45 and 7DT70 transmission variants which are used in the 997.2, 987.2, 991.1, and 981.1 from 2009 to 2016, both NA and turbos. As docdrs said it would be interesting to see your fault list as it may give us some general clues, but people working the 911/Cayman PDK's should be cautious about reading too much into it. I'm interested in your experience as I'm trying to unravel the whole TCU to PDK interaction, but I have no idea if the Macan transmission is comparable to the ZF discussed here.

If you do start a new thread in the Macan section please post a link here so people here can find it.

997ajk

Macan PDK is closely related to Audi DL501 tranny found in Audi S6. Which should be a BorgWarner transmission AFAIK.


Some reading:
https://forums.audirevolution.net/t/...scussion/16069

Own Goal

Been watching but little posting since last July. However, really nice job on this subject PV997. Seems likely have found THE main problem ( distance sensor ) and now an aftermarket solution. Have not had any codes (yet) on my ‘09 911S with PDK, 58k miles. I would like to ask if others have perhaps had these two issues.
> Saw this one with a video this week on 992 area. Bucking and surging when accelerating in Sport mode in second gear. Had this happen just once but sure got my attention.
> More common is when parking , especially on an incline, when going from fwd to reverse or the opposite car acts like a rookie slipping the clutch and grabbing.
But again, I have never kicked any codes. PDK service was done at 43k miles like 5 years ago.

PV997

Thanks Own Goal. My 2010 TT does the exact same thing you mention above, particularly when cold, and I think it's just the nature of the beast.

The 991.1 made changes to how the PDK fluid cooling system is regulated, I think part of it may have been to get the fluid up to temp quicker. My suspicion is that the 997.2 PDK just doesn't do a very good job of compensating for clutch pressure when the fluid is cold. Also, the switch from R to 1st is the only normal gear transition that uses the same clutch for both gears (unlike 1 to 2, 2 to 3, etc.), so that may play a role also. Last off, there is no need to quickly engage the gear when going from R to 1st, so Porsche may have done this on purpose for some unknown reason. Bottom line I don't think it's anything to worry about unless it's getting noticeably worse.

I have not heard of the bucking and surging issue but it could be a sticky solenoid or response to noisy sensor data. That's where I'd look first.

Own Goal

I had a feeling that slip was just a first gen bug. Just live with it. That wild bucking surge was a one time deal but mention it since a new 992 had a video of it happening. Must have been more than once since could video.
im just glad you guys have gotten to place where we have reasonable chance of fixing the darn thing when goes no bueno. This no fix, $12-18k exchange is about same bad as the 996 IMS deal was. Been watching a PBS show on German WWII weapons all being “over engineered”. Guess some things don’t change.

Pinkawa

Thank you PV!

i programmed the TCU new with software T_82, then cleared all fault codes as prompted by the piwis.
I ran the calibration with parts replacement and about 30 seconds it in it stops without any activation of shift rods and the protocol gives a „CAN signal failure gateway“ (pic attached). Also there were the following fault codes in the DME
P1691 communication TCU gear box (no signal)
U0101 communication TCU gear box (no signal)
P1628 communication TCU manual gear box (no signal).

Since I updated the TCU software I thought the DME software would not be able to communicate with the TCU to trigger the calibration so I ended up updating the DME as well. I cleared all failure codes after this and tried a new calibration.

The result is 3 fault codes in the DME That I had prior to updating showed up again (pic attached),
no fault code in the TCU.

When I check the PDK TCU I get signals of all sensors and actuators.
But the TCU appears not to be able to make any of the actuators move .

Is this solved with a new TCU for 800 dollars? It appears to be fine when programming software update and reading sensor signals .
it lacks where it should get active!
does anyone have a wiring diagram ? Maybe i did not connect a plug back when I put the engine back in …….
Is a new TCU the part that will solve the problem ?

i mean I replaced just a dumb sensor. All other parts stayed !!
TIA