Have a one month old 991 with 2,000 km on it. Hoping the fuel economy will get a bit better than it is now. Does it?

 

What range are you getting hawc? I'm returning 26mpg average Over first 2000 miles with 3.8 engine. I drive a mix of spirited and gentle commute. I can easily get > 30 on motorway normal cruising (38 is best I've achieved but that took effort!)
Overall I'm very happy with this as it is better than my AMG but I haven't noticed it improving with age yet...Quite the opposite as I get more confident on the twisties!

 

I have 9.5K miles and my average mpg is 14-15...I guess it's my driving style

 

Yes it does. I have driven mine about 40000 km and the fuel economy has definitely improved.

 

Wow that's a 12 MPG difference between you two.

I'm getting 17mpg. Mostly city, with a little bit of highway.

 

There is a perception that during the break-in period the mileage is a bit lower.. I think there is definitely some effect during the first few hundred miles, but the idea of the engine loosing up significantly at 10K or 20K is something of a myth with any engine and drive chain.

I suspect driving habits are much more significant than anything. When you get a new Porsche model I suspect a lot of that has to do with adapting to how you drive the car.. The one thing I did notice with this car (more so than other cars in the past) is that there is such a significant difference between driving in normal vs sport.

My mileage on my normal morning commute when driving conservatively in normal PDK auto is around 23 to 26... However when I go into Sport.. it's about 16.. With this engine and the modes there are so many variables that can affect the mileage it just seems that the perception of mileage getting better would be difficult to determine unless you really did a scientific test..

 

Agreed, and there's an even bigger difference when I drive in PDK auto vs PDK Manual. In Manual mode I tend to shfit around 3,500- 4,000 RPM becaus it just sounds so good. In full auto it feels like it never lets it go above 2,000 RPM.

I feel like leaving it in full auto is like putting it on autopilot where switching to manual mode is like lighting the afterburners.

 

On the freeway, with cruise control set for 70 mph I get about 28 mpg. On the track I get 8-10 mpg, but in general I just don't pay attention to it.

 

No wonder I was James May on the top gear personality test

 

Bought my 991 S X51 to be driven/used like a sports car. Fuel mileage of no concern but do get 25+ mpg (US Gallon) on highway.

 

I believe that MPG is the last thing that I'd even think about owning a Porsche.

Get a Prius!

 

Has anyone noticed any difference with start/stop activated?

 

I tend to agree in general with your sentiment. But the practical issue is range... and specifically how often I have to drag my lazy a*ss out at the gas station.. (for some reason gas stations are one of my least favorite places and activities in the entire world.. I just hate the rush hour cluster of the retards dance in at the gas station at rush hour)

As a DD and a 16 gallon tank. when I just drive mellow in Auto/Normal (yes I understand why would someone do that in a porsche I can easily go a week and a half as I'll get 23 to 25 Mpg on my routes.

If I drive like I just stole it in Sport+/manual , (which I often do) I'm lucky to make it through thursday before I'm refueling.

It's not so much being cheap (as I never really pay much attention to the cost), it is that I am Lazy..

 

I had it on for the first couple weeks I had the car (until I figured out how to disable). And didn't notice any difference.. but I don't spend a lot of time sitting at stoplights.

I think it would help maybe if you tended to drive in very contested city traffic with lots of time spent sitting at stoplights.. I'm not even so sure it is as much about saving fuel as it is an emissions reduction trick.

For me it just served to scare the crap out of me when it kicked in (or off)

 

There are different results for different driving. Commuting around DC I get around 20 average. On a recent ~150 mile trip from Philly area to DC area in full economy mode (e.g. coasting, start stop, auto) the readout said 31.5 mpg and 68 mph *average* speed: EZPAss and :-) driving. Playing the PSE organ in sport manual, ~17.