Owners report 25.8 mpg from a Porsche 911 (997/2), about 90% of the official figure. On its NEDC-tested engines that is 90%, better than typical: the median NEDC-tested car in this 8,216-engine dataset returns 82%. The tables below give the figure for every engine and generation we hold. Add your own at the bottom and the averages get better for the next buyer.
25.8mpg
Real-world average, all engines
90%
of the official combined figure
20–29
Range reported by owners (mpg)
33
Owner submissions
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Porsche 911 (997/2)
2008–2011 · real average 25.8 mpg · owners report 20.0–29.0 mpg · 33 submissions
Engine
Official (NEDC)
Official (WLTP)
Real MPG
% of official
Owners report
Carrera
29.4
–
27.3
93%
–
Carrera 4
28.0
–
–
–
–
Carrera 4 Cabriolet
27.4
–
–
–
–
Carrera 4 Cabriolet PDK
27.4
–
–
–
–
Carrera 4 PDK
28.0
–
–
–
–
Carrera 4S
28.5
–
–
–
–
Carrera 4S Cabriolet
28.2
–
–
–
–
Carrera 4S Cabriolet PDK
30.7
–
–
–
–
Carrera 4S PDK
31.0
–
22.4
72%
–
Carrera Cabriolet
28.5
–
–
–
–
Carrera Cabriolet PDK
28.5
–
–
–
–
Carrera S
27.4
–
26.6
97%
25.7–27.6
Carrera S Cabriolet
27.4
–
24.1
88%
–
Carrera S Cabriolet PDK
27.4
–
24.0
88%
–
Carrera S PDK
27.7–29.4
–
27.6
97%
–
Targa 4
28.0
–
–
–
–
Targa 4 PDK
27.4
–
–
–
–
Targa 4S
26.9
–
25.5
95%
–
Targa 4S PDK
26.4
–
23.1
88%
20.8–25.4
All figures in miles per gallon (UK). “Owners report” is the spread of individual submissions for that engine.
Add your Porsche 911 (997/2) Real MPG
What does yours actually do? Read it off the trip computer over a full tank or work it out from litres and miles. No postcode, no sign-up. The more people add, the better the averages get, and this page stays free.
Porsche 911 (997/2) fuel economy questions
What is the real-world MPG of a Porsche 911 (997/2)?
Owners report an average of 25.8 mpg across all Porsche 911 (997/2) engines with data, about 90% of the official combined figure. The engine tables on this page give the figure for each engine and generation.
Why is the Porsche 911 (997/2) real MPG lower than the official figure?
Official figures come from a laboratory test cycle, not the road. Cold starts, short trips, hills, load, tyres and driving style all cost fuel the test does not see. A gap of 10 to 30 per cent is normal; a much bigger gap on one engine usually points at a fault, a heavy right foot, or a diesel that never gets warm.
Where did the Honest John Porsche 911 (997/2) Real MPG page go?
The site closed in August 2026 and its Real MPG section went with it. This page is where the Porsche 911 (997/2) figures now live: rebuilt from the archived dataset, with the official figures kept alongside, and reopened for new submissions.
If you used the Honest John Real MPG section before the site closed in 2026, this is where the Porsche 911 (997/2) figures now live. The owner-reported averages above were rebuilt from the archived dataset (archived page, 2026-06) alongside the official NEDC and WLTP figures and new submissions from CarAdCheck readers, and the section is open so they keep improving. Real-world figures also feed the running-cost estimate in our free advert check.
CarAdCheck is not affiliated with Honest John or Volkswagen Financial Services. How we rebuilt Real MPG.