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Problem after PDK clutch oil service

MrksD

Member
Joined
22 Jun 2017
Messages
15
Hi Porsche friends,

had my car taken in for the PDK clutch oil service (6 year interval). My car is from 2009 so it is a bit late. I have had the car since summer last year.

The service was done at an independent specialist with the right OBD tool, official instructions, maintenance parts etc: Oil drain and top up between indicated engine temp, then follow OBD tool instructions and let the automated calibration procedure run.

The engine speed is now unsteady under load when accelerating approaching 2000rpm. Engine speed trace would look like a jigsaw on an oscilloscope. The car runs fine at steady state and in general above 2000rpm. To be honest it is a minor instability but definitely enough to notice. It s clearly visible on the needle and also from the engine noise at any vehicle speed in the respective gears. It feels as if the clutch is slipping.
The problem is present in all gears, manual/auto mode, sport mode etc.

There is a more fundamental PDK calibration process that can be run via the OBD tool. This was also done but it aborted half way through. Car was immobilised because of this and then taken to OPC. They re-flashed the gear box and said everything is fine. Car is running again but the problem is still there....

Any thoughts/experience on this would be much appreciated.

My car: 997C2S from 2009

Thanks.

M
 
Sorry I can't be of huge help but I've just had mine done with the OPC.

They updated a software mod, carried out re adaptation and changed both transmission and clutch fluid at my request (only clutch fluid was due). I don't mean to sound all smug but it performs much more crisply than before.

Not sure if OPC have the upper hand with software/firmware or whatever. Might be worth giving them a call. It sounds like you have some kind of fueling issue from the ECU. Good luck and let us know how you get on :thumb:
 
Thanks for the quick response.

I think fueling can be ruled out for now as the engine speed changes without any change in vehicle speed e.g. driving on the motorway in 7th gear: any fueling related change in engine speed would be associated with a significant change in vehicle speed if there is no slip in the transmission somewhere.

M
 
Norfolk & Idea said:
Sorry I can't be of huge help but I've just had mine done with the OPC.

They updated a software mod, carried out re adaptation and changed both transmission and clutch fluid at my request (only clutch fluid was due). I don't mean to sound all smug but it performs much more crisply than before.

Not sure if OPC have the upper hand with software/firmware or whatever. Might be worth giving them a call. It sounds like you have some kind of fueling issue from the ECU. Good luck and let us know how you get on :thumb:

Out of interest how much did that cost at OPC?
 
Can i just break this down a bit ..

The oil service was done at an Indy .. the tester is used to open some valves so that the correct oil lvl can be obtained .

Its not a calibration .. is this a seperate thing the indy did ?

Is this the calibration that failed and immobilised the car ?

Was the car fine before the calibration ?

You dont tend to run a calibration process without good reason .. was there a fault prior to this ?

OPC reflashed the Control unit i take it ?

Engine trace .. im not sure what value you are looking at here .. a speed sensor for the PDK ?

Your problem would seem to me to be the set points of the calibration have not yet been learned .. ive not done this in a few years but you had to drive the car at a set rpm for a set time in a set gear ..

you repeated this in different gears and rpm .

It may be different now .. normally an OPC would do this .. you drive the car with a tester to check when they have been learned .
 
MrksD said:
Thanks for the quick response.

I think fueling can be ruled out for now as the engine speed changes without any change in vehicle speed e.g. driving on the motorway in 7th gear: any fueling related change in engine speed would be associated with a significant change in vehicle speed if there is no slip in the transmission somewhere.

M

Not sure if it is a similar issue to this one...... https://www.pistonheads.com/gassing/topic.asp?h=0&f=48&t=1705116&i=20

and

https://www.pistonheads.com/gassing/topic.asp?h=0&t=1690396&mid=455737

If so could be worth trying to get hold of the OP through PH to see if/ how they resolved it.
 
Bolorunner said:
Norfolk & Idea said:
Sorry I can't be of huge help but I've just had mine done with the OPC.

They updated a software mod, carried out re adaptation and changed both transmission and clutch fluid at my request (only clutch fluid was due). I don't mean to sound all smug but it performs much more crisply than before.

Not sure if OPC have the upper hand with software/firmware or whatever. Might be worth giving them a call. It sounds like you have some kind of fueling issue from the ECU. Good luck and let us know how you get on :thumb:

Out of interest how much did that cost at OPC?

It was in 2 parts. I had to take it back for transmission oil change. This plus re adaptation/software update was £262 IIRC. Which I thought was very reasonable. This was all after my main service which captured the clutch oil change... I'm working away at the moment and don't have the breakdown receipt. But all in all the PDK bit wasn't too brutal.
 
deMort said:
Can i just break this down a bit ..

The oil service was done at an Indy .. the tester is used to open some valves so that the correct oil lvl can be obtained . Yes correct.

Its not a calibration .. is this a seperate thing the indy did ? Yes the Indy launched a calibration process via the OBD tool. This was done after I found the engine speed problem.

Is this the calibration that failed and immobilised the car ? Yes it failed half way through.

Was the car fine before the calibration ? The car was fine before the oil change. After the oil change the engine speed problem occurred. Then I took it back. They repeated the oil change procedure. Issue still present. Then launch the stationary calibration process. Car was immobilised...

You dont tend to run a calibration process without good reason .. was there a fault prior to this ? The fault was the engine speed instability.

OPC reflashed the Control unit i take it ? Yes.

Engine trace .. im not sure what value you are looking at here .. a speed sensor for the PDK ? Yes engine speed trace.

Your problem would seem to me to be the set points of the calibration have not yet been learned .. ive not done this in a few years but you had to drive the car at a set rpm for a set time in a set gear ..the Indy mentioned this procedure. This has not been tried yet.

you repeated this in different gears and rpm .

It may be different now .. normally an OPC would do this .. you drive the car with a tester to check when they have been learned .
 
maph said:
MrksD said:
Thanks for the quick response.

I think fueling can be ruled out for now as the engine speed changes without any change in vehicle speed e.g. driving on the motorway in 7th gear: any fueling related change in engine speed would be associated with a significant change in vehicle speed if there is no slip in the transmission somewhere.

M

Not sure if it is a similar issue to this one...... https://www.pistonheads.com/gassing/topic.asp?h=0&f=48&t=1705116&i=20

and

https://www.pistonheads.com/gassing/topic.asp?h=0&t=1690396&mid=455737

If so could be worth trying to get hold of the OP through PH to see if/ how they resolved it.

The YouTube video of the first thing you posted is exactly the issue I have. I read the thread. Sounds like a sad story with no solution posted. Does anybody know if that story was continued in a different thread?

M
 
MrksD said:
The YouTube video of the first thing you posted is exactly the issue I have. I read the thread. Sounds like a sad story with no solution posted. Does anybody know if that story was continued in a different thread?

M

No, I have not seen a different thread. Try PM'ing him through PH, he seems like a pretty active member.

Best of luck.
 
Bolorunner said:
Norfolk & Idea said:
Sorry I can't be of huge help but I've just had mine done with the OPC.

They updated a software mod, carried out re adaptation and changed both transmission and clutch fluid at my request (only clutch fluid was due). I don't mean to sound all smug but it performs much more crisply than before.

Not sure if OPC have the upper hand with software/firmware or whatever. Might be worth giving them a call. It sounds like you have some kind of fueling issue from the ECU. Good luck and let us know how you get on :thumb:

Out of interest how much did that cost at OPC?


OPC solihull charged the Indy about 400£ just for getting the gear box running again. I haven't seen the line items but it sounded like they only refsshed the control module.
 
Ive seen something similar on a Tip box .. in that case it was the torque convertor clutch .

Doesnt help you as such but reinforces its a gearbox issue .

For me its a load signal problem and im back to it needs a calibration ..

This is the sort of problem that at OPC we would put a ticket into technical explaining the problem and they would give us a test drive routine to calibrate the PDK.

It may have changed now but i think thats more the route to go .

I cant see a problem occuring with the speed signal because of an oil change .. i know the temp sensor can be changed but im pretty certain the speed sensor cant so its a new PDK box if thats at fault .. which i cant see from what you have said .

Logically its a software fault .. it failed .. it was reflashed but as best as i can tell its not fully calibrated .
 
There is a bloke with a 997TT who writes a running report in Total 911.

In the current edition he tells that he had his PDK oil changed, and disconnected the battery and left it for a bit to reset the ECU. Said it ran much better, though he did not say he had a similar fault before, just that it felt 'sluggish'.

Might be worth a go?
 
deMort said:
Ive seen something similar on a Tip box .. in that case it was the torque convertor clutch .

Doesnt help you as such but reinforces its a gearbox issue .

For me its a load signal problem and im back to it needs a calibration ..

This is the sort of problem that at OPC we would put a ticket into technical explaining the problem and they would give us a test drive routine to calibrate the PDK.

It may have changed now but i think thats more the route to go .

I cant see a problem occuring with the speed signal because of an oil change .. i know the temp sensor can be changed but im pretty certain the speed sensor cant so its a new PDK box if thats at fault .. which i cant see from what you have said .

Logically its a software fault .. it failed .. it was reflashed but as best as i can tell its not fully calibrated .

Thanks for your advice. The car is going back to OPC Solihull now. Fingers crossed it s SW issue and no HW replacements needed. I will post updates here when I get them.

Thanks.
 
Robertb said:
There is a bloke with a 997TT who writes a running report in Total 911.

In the current edition he tells that he had his PDK oil changed, and disconnected the battery and left it for a bit to reset the ECU. Said it ran much better, though he did not say he had a similar fault before, just that it felt 'sluggish'.

Might be worth a go?

Hi Guys,

I am 'that bloke' and my issue was not the issue described above.

Here's what I wrote for Total911...

After last month's Major service at DW Performance I sent oil samples from my engine and gearbox to Millers Oils for testing. At ~£30/sample it's an affordable way to diagnose issues by identifying 'stuff' that shouldn't be there.

Within days reports were emailed to me and they made for interesting reading. First the good news; after 8,500 miles the engine oil was still within spec for a 0W-40 which means that it was still fit for the task of protecting my engine. A small amount of fuel showed up in the oil which is consistent with a car that generally does shorter runs in richer 'start-up' mode. This fuel is typically burned off when the oil runs very hot for a long time, such as on longer journeys. Particularly low wear levels of the Boron and Molybdenum from the oil additive pack also indicate that the engine is in very good condition having not consumed them. Happy days!
It will be interesting to test the Millers CFS 10W-50 NT+ when it gets changed to see how well it has performed.

However, the Gearbox oil told a different story. This factory-filled 75W-90 was almost 8-years old when drained with 35,000 miles under its belt and it was way past its best. The results showed a drop of 30% in viscosity taking it out of spec and making it more of a 75W-80 oil. Clearly this transmission oil was no longer in a fit state to take the best care of a PDK transmission handling 500+BHP and 700 torques.

Thankfully, wear debris was negligible so no harm done, but if I'd kept the oil in there for another 4-years as Porsche advises I think the story might be very different indeed.

My conclusion? Get your PDK oil changed at least every 6 years or 30,000 miles for maximum protection of that hard-working £15,000 part.

But what of the 'feel' of the car since its service? Well, driving home it felt a little sleepy, a bit laggy. I wondered if the lower engine friction left the ECU just a little 'out of sync' on the supply of fuel and air etc. so the next day I disconnected the battery and left the car to reset. After reconnecting the power, I fired it up and headed for my favourite local roads at a sedate pace while waiting for the engine temperature to rise. And then I let rip and the car took off.

I could clearly feel the difference in the immediacy of the acceleration. It was readier, happier, and quicker to gather speed. Could it be the placebo affect? I couldn't be sure but I'd love to know. The easy way to find out would be to dyno the car but without a baseline before the oil change its going to be tricky to measure the difference the oil makes unless I can get a 'typical' dyno result for a stock 997.2 Turbo PDK.

I reached out to Ken Napier at respected Porsche tuning house Nine Excellence (9e) to ask for some insight. Ken explained that the PDK consumes about 10% of the hp, typically leaving the 997.2 Turbo with ~450 whp. Ken was also quick to point out that the 50hp lost through the PDK is far less than a manual that typically loses about 15% or 75hp. Great news. So 450bhp is my benchmark, now I just need to find a trustworthy 4wd dyno.


Note: I put the very slippy Millers NT+ oil in the engine and the gearbox. It is quoted as reducing friction and heat which will change the engine's ability to rev up faster and more freely. I *think* i felt this but as I say above, I can't be certain.

Hope you get a fix soon - sounds very annoying.
 

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