omniphil

It seems like this is a somewhat common issue with 2017-2018 S and GTS's once they get over 40k miles or so.
I want to start a thread here to hopefully narrow down the issue.
I have had the Macan into Porsche twice already for this issue and there are no problems found (They can reproduce the issue fairly easily as it happens all the time)
There are no codes being thrown by this issue. Making diagnosis fairly difficult.

When in the 1600-2200 rpm range and you are driving lightly like on the highway and come off the throttle a little bit and then gently reapply the throttle more often then not the car stumbles.
It feel like the clutch opening and closing very quickly. Sometimes the stumble is pretty severe sometimes it is quite soft..

I have had a transfer case done for the second time recently, that did not make a difference.
I have new downpipes, new motor mounts, new diverter valves, new air oil separators. PDK has been serviced as well.
I currently have both pressure sensors on order, after that I am thinking cam position sensors...

I feel like this has to an electrical issue with some sensor, at least that's what experience tells me but who knows...

Any and all help is appreciated. The Macan is in really nice shape and drives so smoothly/runs great otherwise. Its such a frustrating annoyance that I see a fair bit of posts about but no resolution other to trade in the car for a 2020 or newer...

Cnair

Did they try pdk recalibration to adapt for clutch thickness? In your case it doesn't look like you have high miles. My wife's 18 GTS has a stuttering issue on stop and go traffic. it's not stalling but it feels like the pdk is hunting for the right gear.

omniphil

They didn't. Something about can cause more problems with the mechatronic unit...

I have the stuttering issue in traffic as well, and it's the same issue. When you're crawling along with small throttle movements the call will studder sometimes. for me it can happen as low as 1400 rpms...

///Bruce

The way you described the issue happens in what might be heavy traffic. Having to get on it for a moment, back off some and then get on it again.
Q: what gear is it in? C, Sport? Sport+?
Q: Does the DCT change up or down a gear while this issue is happening? Which ones?
Q: You said you’re running down pipes. Did you tune it in any other way?
Q: did it happen PRIOR to the down pipes?

I’m wondering if it’s not sure what gear it needs to be in. Have you thought that the down pipes are the culprit? Or, as you mentioned it ‘feels like’ a fluttering valve in the Mechatronic module.

And since it’s not throwing a code, if it were me, I’d take a chance and drop the coin get all my parts and pieces installed and get a BGB tune.

omniphil

The stumble happens in all gears and in all modes.. (Normal/Sport/Sport+) Happens in Manual mode or Automatic mode. Hot or cold, dry or wet. It's always there...
The DCT gear indicator does not indicate a gear change, for example it happens frequently on the highway just cruising as in 7th gear I am right around 1800 RPMS. So there's no more gear for it to be trying to switch into...
The downpipes are new factory downpipes (Replaced under warranty as there is a know rattle/vibration issue with those)
It has happened since I had the Macan which was 40k miles. (and before all the warranty work done). I'm at about 49k miles now and have been through a bunch of replacement parts by now, however no change at all.

The tough part is that its a narrow range of RPMs that it happens at, but unfortunately it's the most common range for me to be in as highway driving puts me right there and If I switch down into sport mode for backroads it also keeps me right in the range.
I can go to manual mode and keep it above 2200 rpms and never have the issue, but that's not always ideal...

wwahl

Are any of you folks with this problem using the Pedal Commander? When I installed if, this cured all sorts of problems for me.

omniphil

I haven't tried a pedal commander, but this is more rpm dependent.... I would certainly get one if I thought it would fix it though

Larson E. Rapp

How about reverse gear? Does it happen there? Kind of an off-the-wall suggestion but it might provide a clue.

Does turning off PSM make a difference?

There's an interesting post by Sajan in another thread in which he uses a PIWIS to graph all sorts of operating parameters, in an attempt to narrow down a similar-sounding issue with some of the 9A1-based cars. I would try to duplicate some of the diagnostic steps he has been taking. A lot of the reasoning in that thread seems to make good sense, even if it hasn't revealed any smoking guns yet.

omniphil

Thanks a bunch for pointing me to that thread, the RPM range is different but it certainly sounds like the same issue.
I am certainly going to try the PSM on/off trick.
Testing in reverse is a good suggestion too....

FLACHT6_pilot

I have the same exact issue on my '17 GTS.

The OP describes it very well. It happens when you go from zero throttle to 10-30% throttle. It stumbles, sometimes slightly, sometimes more significantly.

It happens in all modes, normal, sport, sport +. I have a fresh transfer case so it has nothing to do with that.

It does not happen if you step on the throttle significantly - anything >40%.

I've read about it on RL and other Macan forums, but no one seems to have a answer. I agree with the OP that it is likely electrical/sensor in nature.
No codes found during a scan and no clues....wish I had more to contribute other than saying you're not the only one...

wwahl

Do either of you two use a pedal commander, or equivalent?

omniphil

How many miles on your Macan and how long have you owned it?
When did you notice it start happening?
(It seems to effect most 2017 and 2018 GTS's some people just don't notice it)

omniphil

I do not use a pedal commander (I did however try one just to see if it would help, but it made no difference)
It also happens when cruise control is on so I know it's not related to the pedal/sensor in any way.

RENNtorq

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RENNtorq

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