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Discussion Starter · #1 ·
Our '09 CS with PDK now has over 5000 miles on it and continues to have an occasional issue with the PDK when starting out. Curious if anyone else has this issue and if you have had it resolved.

When starting out normally (not heavily accelerating, just going with the flow), on occasion the PDK will, for lack of a better term, disengage the clutch after a fraction of a second of normal acceleration. So the car will, for an instant, start to accelerate normally (as in gets to a mile or two per hour speed, so very slow) and then there is a clunk/jerk as the PDK takes itself out of gear. So you have to get off the gas and then resume the acceleration normally.

This happens only every once in a while - not every start. There doesn't seem to be any pattern to this, so we cannot take it to the dealership and duplicate the issue. Nor is there any guarantee that if we left it with the dealership (something we don't particularly care to do in the first place) that they would be able to duplicate the issue.

This is a bit distressing as it doesn't sound too healthy. Not sure if it is actually doing any harm to the transmission, but it certainly doesn't feel/sound good.

It is almost like there is a software issue and the PDK gets confused on occasion during normal acceleration. We have never had this issue when accelerating briskly (I can see it now - solution is to accelerate quickly all the time :) ).

Has anybody else experienced this issue? If so, did you get it fixed?

Thanks!
 

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Could this be the issue?

My service advisor told me that they performed the following TSB: "WM 373025 ELIMINATING TRANSMISSION SYMPTOMS--RE-PROGRAMMING DME CONTROL UNIT AND PDK CONTROL UNIT (VEHICLE JERKING WHEN CHANGING GEAR)." The TSB was introduced on Sept. 5, 2008. My vehicle has a build date of Feb.2009. All I know is that the drive is now much smoother in sport mode -- the abrupt downshifting from 2nd to 1st is gone!
Given how our cars are rolling computers nowadays, I'm sure there are many tweaks that need to be dealt with via the software as time goes on.
 

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It simply requires a software reset, this goes for DSG boxes as well.
 

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Just wondering, do you drive your car hard or baby it? The PDK is known to "adapt" to your driving style.
 

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Discussion Starter · #5 ·
Just wondering, do you drive your car hard or baby it? The PDK is known to "adapt" to your driving style.
We drive it like a normal car. We didn't spend this kind of money to abuse a beautiful piece of art.

Regardless of the driving style, when you pull away, the transmission shouldn't drop out of gear. You are correct that the PDK learns your driving style, but only for a short time. In other words, if you accelerate hard, it will keep the RPMs up for a short time in anticipation of you driving more aggressively. After a short time of not driving it hard, it goes back to its normal shift patterns. Then again, you already know this with your PDK.
 

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None of the PDKs I've driven - either 987, 997, or Panamera has done this. I've driven them hard on the track, and also just "regular" driving. As much as you hate to do it, you should probably contact your dealer and have it looked at. There have been some software glitches that have popped-up here and there, and this could be one of them. I doubt you're going to find an answer here.

brad
 

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Probably needs a software reflash.


Any chance of shooting a video of it while it's happening for us to see?
 

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I have a new Cayman S with about 4500 miles. Was having some harsh noise (clank) going slow speeds 1 st and 2 nd gear. They did the software uodate for the PDQ and it has been a little better but not perfect. I still have some noise at low speeds and rather slow going into reverse. I have a BMW 540i with triptronic and it is as smooth as glass going into gear.

When I get on it (after appropriate breakin, I could not wait to floor it) the car is very smooth up throught the gears. A smooth flow of power. Impressive!
 

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I have a new Cayman S with about 4500 miles. Was having some harsh noise (clank) going slow speeds 1 st and 2 nd gear. They did the software uodate for the PDQ and it has been a little better but not perfect. I still have some noise at low speeds and rather slow going into reverse. I have a BMW 540i with triptronic and it is as smooth as glass going into gear.

When I get on it (after appropriate breakin, I could not wait to floor it) the car is very smooth up throught the gears. A smooth flow of power. Impressive!
Two very different types of transmissions,.....one a dual-clutch auto with no torque converter trying to act like a "classic" automatic transmission and offer the performance benefits of a manual. The other a traditional automatic with a torque converter with the ability to change gears manually if the driver wishes.

Every PDK that I have driven had some low speed quirks to it. Given its nature, it will never be as smooth as a true automatic as the buffering effect of the torque converter is not there. It is akin to driving a manual transmission at low speeds,....in some instances it can jerk a bit and make a few different sounds.

As most have found, most of the benefit of PDK is in fairly hard acceleration, where all it is asked to do is engage and up shift as fast as it can when it is supposed to. With this it doesn't have to deal with part throttle conditions, on/off throttle, downshifting, braking, etc. all at the same time. It will never be perfectly smooth here.
 

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I have a new Cayman S with about 4500 miles. Was having some harsh noise (clank) going slow speeds 1 st and 2 nd gear. They did the software uodate for the PDQ and it has been a little better but not perfect. I still have some noise at low speeds and rather slow going into reverse. I have a BMW 540i with triptronic and it is as smooth as glass going into gear.

When I get on it (after appropriate breakin, I could not wait to floor it) the car is very smooth up throught the gears. A smooth flow of power. Impressive!
That is normal, PDK is clunky transmission.
 

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Glad for the feedback on the PDK. When you buy a car you love you hate to thin that something just might not be right in your car. As I said when you really accelerate you can't beat how quickly it up-shifts. This is my third Porsche both prior were manual. A 1969 911T targa and a 1973 914 2.0. I believe the 911 had a torque converter. Could that be right? That was an amazingly fast car. :)
 

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:hilarious:

O.K., I have picked myself off of the floor and just in case you weren't trying to be that funny, NO your 911 manual transmission did not have a torque converter. Torque converters and automatic transmissions are fluid driven devices. Manual transmissions and now the new dual clutch transmissions are mechanically driven devices. In my humble opinion you might be surprized if you could drive your old '69 911T and then your Cayman on a road where you can judge performance. Perhaps you have yet to discover how fast your new Cayman is?

Check for dealers you can trust on this forum or through your regional Porsche club, and get your car fixed. You are going to have to trust someone to work on it. You are going to enjoy it much more with out weird shifts.

Good Luck !

Oldster
 

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The 911 would have had a torque converter if it had a Sportomatic transmission, but I'm not sure if this was an option on the '69 911 T or not.
 

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Sportomatics were available from 1968-1979, and could be ordered with all 911s.

brad
 

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Discussion Starter · #15 ·
Check for dealers you can trust on this forum or through your regional Porsche club, and get your car fixed. You are going to have to trust someone to work on it. You are going to enjoy it much more with out weird shifts.


Oldster
I wish we had a choice in dealerships. Unfortunately there are only two in Arizona and only one in the area in which we live. Not sure if it is worth a 2+ hour drive to Tucson to visit another dealership since they might be just as fun to deal with.
 

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WHT09CS,

My 09 CS with PDK will do the same thing you have noted. If I take off slow in normal mode with a slow throttle input it will on occasion balk a bit. I have found that if I increase the rate on the throttle a bit I get a much smoother response.

I did check with my dealer and the Porsche rep in my area. Both said this is not considered abnormal.

I didn't consider mine a work of art until after the first 10 hot laps on track ;)
However, I have to admit the first few rock chips and star crack in the windshield were not welcomed.
 

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I and others have noticed that the PDK doesn't do its thing so well until the engine reaches normal operating temperature. What you have is NORMAL.
On startup in the AM, it can be clunky for the first 10 minutes until warmed up. But on start up mid-day after usage it is usually perfect right out of the gate (unless the engine has completely cooled back down 100 percent).
 

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Discussion Starter · #18 ·
WHT09CS,

My 09 CS with PDK will do the same thing you have noted. If I take off slow in normal mode with a slow throttle input it will on occasion balk a bit. I have found that if I increase the rate on the throttle a bit I get a much smoother response.

I did check with my dealer and the Porsche rep in my area. Both said this is not considered abnormal.

I didn't consider mine a work of art until after the first 10 hot laps on track ;)
However, I have to admit the first few rock chips and star crack in the windshield were not welcomed.
How does one get in contact with the Porsche rep in our area?

We too have had our fair share of windshield damage. Had to have it replaced after two weeks of ownership and in addition to a good number of chips in the 'new' windshield, we just got our first star crack that is getting repaired tomorrow. Never had this much problem with windshields before.
 

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Discussion Starter · #19 ·
I and others have noticed that the PDK doesn't do its thing so well until the engine reaches normal operating temperature. What you have is NORMAL.
On startup in the AM, it can be clunky for the first 10 minutes until warmed up. But on start up mid-day after usage it is usually perfect right out of the gate (unless the engine has completely cooled back down 100 percent).
I guess if the issue only happened on a cold engine, then I would not be so worried. However, the initial issue that I started this thread with happens at all engine temperatures. So it is definitely not engine/transmission temperature dependent.
 

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When starting out normally (not heavily accelerating, just going with the flow), on occasion the PDK will, for lack of a better term, disengage the clutch after a fraction of a second of normal acceleration. So the car will, for an instant, start to accelerate normally (as in gets to a mile or two per hour speed, so very slow) and then there is a clunk/jerk as the PDK takes itself out of gear.
I call it *slip and slap*. It's like a momentary disengagement of the tranny while in first gear, then an abrupt reengagement. The abrupt part (jerk) is due to the revs climbing. No clanking or clunking. Maybe the PDK was thinking about upshifting then changed it's mind?

Glad to see it might be covered by a TSB- I'll need to investigate the next time I take the car into the dealership.
 
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