ncp

Over 3k miles driven since new and wondering why I don't notice a difference from within the cabin while toggling the sport button. Inquire about it while getting oil changed and the tech confirms that it's not functioning. Has anyone else experienced the same? Any ideas what the culprit might be? Light does turn on when the button is depressed.

RockyTopTenn

Which tech? I would think a dealer could tell you what was wrong. There seems to be issues with the vacuum lines, but I'm no expert on this. There have been several threads mentioning this on here...

ncp

The dealership tech. Had the car in for oil over the weekend while they had a limited crew. Couldn't get the car scheduled until next week to have it properly scoped out.

ncp

So I thought to myself this morning, surely the tech that determined I had an issue that required further diagnostics gave my exhaust at least a visual once over. To my amazement, a quick look at the undercarriage showed an obvious disconnection of one of the hoses to the actuator. After 3k miles on the clock, never realized what the car was supposed to actually sound like with the button depressed. Ridiculous.

Mech33

With the line disconnected you’ve been driving with the
sport exhaust on all the time! Now you’ll get to experience it in “quiet” mode.

ncp

Actually, just the opposite. I have definitely been in quiet mode with hose disconnected. I believe the system has to be plugged while hose is disconnected to remain in sport exhaust mode.

Todd B

no you haven’t been in quiet mode, when the hose is disconnected the valve is always open, aka loud/sport mode.
Plugging the line only stops the vacuum leak.

erik_plus8

The actuator is springloaded to default OPEN - if no vacuum (line disconnected) the valve (s) is (are) open. Check for your self. Let someone start the car, look at the valves. Let PSE be off and you will see, when vacuum builds from engine running, the actuator will pull the valve to closeed. Let friend push PSE on, and you will see actuator return to resting (open) position.

What you probably need to know: The only time you'll be able to tell a difference between PSE on/off from inside (or outside) is at idle... That's because even in PSE ON the valves close as soon as you start rolling, and do not open again until ~4000rpm. This has to do with passing sound legislations. Funny thing is that also in PSE OFF, they open, although *maybe* a little (a few hundred revs) later in the rev range, this is because reducing backpressure and increasing performance at high revs.

So what good does the PSE really do? In my view, not much. I have concluded It does the opposite what you think , it reduces the sound in certain areas, most noticeably in the 1500-3800 rpm range, where an open PSE creates a quite annoying booming/drone noise. (This you have already experienced, since you have been running with the lines off) I actually think this is the real reason for the PSE, to take out drone/booming and of course pass sound legislations. It never increases sound anywhere.

All above true for 991.2 GT3, I do not know how Carreras, Turbos, 718s, Macans or other PSE equipped cars work. I can imagine or even assume the control logic is different in different cars.

Ducati1199

To confirm what others have said - a number of people deliberately pull the hoses off and plug the vacuum lines with a screw. Once disconnected the valves stay open all the time and you're in loud mode. The PSE button then does nothing.

ncp

Only one of my lines was disconnected, so I'm not sure how that may have affected the mechanics of what was happening with the system as a whole, ie one side vs the other. Perhaps with one sort of working and the other not at all?? All I know is that for the first time since owning the car the opening and closing of the valves is now pronounced. Once reconnected, I suppose this gave the illusion that at ~3,800 and up the car was louder than before when in fact, as you're saying it's now just quieter from ~1,500 to 3,800.

One other thing, with the vacuum now sealed I notice more gurgles and pops.

Anyway, appreciate the explanations. Thanks.