BRNGT4

So i noticed at when i reach cruising speed and the car is no longer accelerating, the engine sound changes significantly. It sounds like a droning noise and you can actually feel it in the backrest of the seat. The mechanic in me is telling me this is some sort of fuel conservation mode. Maybe cylinders switching off? Does anyone know anything about this? I cant find any information in the car manual or online.

Mr.Speed

With sport exhaust on or off? Mine with sport exhaust on, changes engine note at 4000 rpm as the valves is programed to open... And on high way when you drive on constant +-4000 rpm, feels like droning a little... And yes it have a cylinder deactivation. You can try to turn off start/stop mode.

"While the new engine employs the usual composite oil pan, forged pistons, and plasma-coated cylinders, it’s the first flat-six Porsche to feature cylinder deactivation. Deactivating the auto stop-start function disables the cylinder deactivation. As in previous GT4s, there are no driving modes"

BRNGT4

Sport exhaust on or off doesn't make a difference. Ill try the auto stop-start today and report back later. If it works i will be ever grateful to Porsche for allowing us to deactivate. Its bothersome!!!

Mr.Speed

Yes, seems they are pushed hardly to comply with the emissions regulations in Europe...

Yellow Submarine

Define cruising speed?

EYEHAVEYOU

It's the cylinder deactivation, you're running on 3 cylinders. Turn auto-start off and you won't have to deal with that anymore

911F1

^I forget. Do you have to press the auto stop start button everytime you turn on the car?
Or does it remember its pressed?

Mr.Speed

Everytime you start the car, same as sport exhaust

Rxpert

That’s annoying AF. My 1/2 price BMW remembers the last setting for Auto Start/Stop. C’mon Porsche

Mr.Speed

I think that also can be related to emissions regulation... Strange that BMW remember that setting

Archimedes

Are you sure? I could have sworn I heard a reviewer comment that it can be permanently turned off, similar to prior variants. That sucks if it's an every time thing.

unclemat

I'd guess the T-Design module that remembers auto start/stop setting would still work.

SToronto

On my 19 Cayenne it has to be done upon every engine start. You can turn off with PCM button, programmable steering wheel button or sport Chrono dial switched to something other than Normal.

911F1

Now that I thought about it longer. I don't recall having to press it every time when I had my 991.
Euro owners help us out. Is it every time?

Archimedes

Yup, it was a one time deal on my 991. Did not have to press it each time that you got in the car. It's the same way on my new M5.