Carlos911

Hello, My first post from sunny Manchester UK, I have read some very informative stuff on here over the years by very knowledgeable people and hope this question can be answered/commented on:

On the way back from shopping yesterday I approached a Tee Junction on a quite steep climbing incline of about 20%
I was behind a couple of cars waiting to turn left, this meant that I had to slowly approach then stop then accelerate carefully to approach the junction.
Now normally in a manual I would feel the clutch bite and control accordingly just to get me up whilst maintaining control.
In other auto cars I own this junction has caused no problems !
The GTS stalled ! It really seemed to struggle with the incline & maintaining power to get me up, it rolled back following the stall and I quickly applied the handbrake, hazards on, moved the selector to park and restarted the engine by which time nobody was in front of me so I gave it throttle and exited left.
What have I done wrong, should the car not maintain power to get me up without a stall ?
Comments or questions please I should not have to avoid this route !
76k miles on the clock

wjk_glynn

I've driven my Carrera S w/PDK up and down the famously hilly San Francisco many times, and I've not had that kind of problem.

Now my approach is to not try and second guess the system. I leave it in D, and rely on the built in hill-hold function (i.e. I explicitly do not use the handbrake).

However, many others have complained that the hill-hold doesn't release quickly enough when you move your foot from the brake to the accelerator, and they've found the hill-hold inhibits initial forward progress. I personally haven't experienced that, but enough others have reported it, that it seems to be a thing on some cars.

I wonder that if your hill-hold was particularly slow to release, it might have caused the stall. But that's just pure speculation on my part.

Oh and the PDK can be clunky/hesitant when initially cold, but it improves after 2-3 mins of driving... just in case the incline is super close to your house.

Karl.

PS: If you haven't already, you should also check out this UK based 997 forum: https://911uk.com/forums/997-2004-2012.16/

Fined

Anything with a clutch in it doesn't appreciate being feathered, and it's best to either be on the gas or off the gas and not just giving it 2% throttle and creeping along/up.

Of all the cars I've had with a dual clutch, any one of them can be inspired to act poorly if they are left in a situation where there isn't a clear directive from the driver in terms of throttle actuation. Kind of like a car with a manual gearbox, if you just give the tiniest bit of throttle from a stop, things might be OK but you can expect to have some friction material burning smell from being in between states of grabbing and disengaging. Different clutches have a different amount of leniency when it comes to very low speed acceleration. Whether it's a single clutch like in a manual or a dual clutch. Some hate it, some let you slide.

Wanted to add: I also have a 2011 GTS PDK.. can't recall it giving me issues ever, lots of miles covered.

Liste-Renn

Agree that the PDK is a phenomenal box when driving with intention.
It will magically pre-select the appropriate "next" gear based on acceleration or deceleration.
When one coasts- not doing either one- the PDK either pre-selects the wrong "next" gear, resulting in a delayed shift to the proper gear...or selects the wrong gear for the conditions and the demand you are placing on it.

That is my experience from 30K+ miles in a 2018 Macan GTS with Sport Chrono driven 99% of the time in SPORT mode/auto.

As suggested above, perhaps the steep/slow combo combined with the hill-hold function input/interference might have resulted in the stall at idle throttle?

My 6MT 997 GTS hill-hold function has never let me down, not in San Francisco nor other challenging inclined roads with full stops.
Nor has the Macan GTS for that matter.

Carlos911

Thanks for this folks

For my RHD vehicle:

I wonder, my normal driving method is by use of 1 foot only (Right Foot) switched between accelerating & braking
Should I us 2 feet in this situation (Left foot on Brake/Right foot on accelerator) to control power/movement on this incline
I know its not really conventional driving for an auto/pdk but I may give it a go ?

Ta

Busta Rib

Your Hill Hold functionality should be engaging on inclines. If it is not, have your car checked out. One or more of the sensors, or something else in the system is likely wonky.

sandwedge

Same here. Two well documented all out failures but when they're working as designed, no issues. Between two PDK cars now I have a total of just above 90K PDK miles under my belt. Yes...two failures requiring full replacement (covered by warranty) sucked but I still think it's a marvel of modern engineering and when they work as they should I never had the issues the OP describes either. Both failures were fairly sudden and didn't deprive me of enjoying the car for an extended period of time. In fact, both were replaced in less than a week as I recall it with perfect functionality in both of them prior to the two sudden failures.

So my PDK experience is that either they work 100% as they should and if they don't, bring it to the shop of your choice and describe the problem. Both my failures basically went from 100% perfect to suddenly limping home with the Transmission Emergency Run light blaring on the dash and call for a flatbed.