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I'd like to check whether the fuel consumption on my cayenne is worse than it should be. I took the below picture after driving through the city


12.5 mpg UK equates to about 10.4 mpg US

When we are stuck in traffic i've seen the mpg figure go down to around 10 mpg (8.5pmg US) and on a normal run it averages around 14mpg (11.7mpg US). We don't exactly put our foot down and are reasonably light on the throttle for these measurements.

Do these numbers sound about right? I've read other owners comments about getting between 16-18mpg on these cars and i'm wondering whether ours is underperforming somehow.

Some things i've checked after reading some other threads:-

  • Engine doesn't seem to be misfiring - spark plugs and coils were changed 9k miles ago (major service at dealer)
  • Oil level seems fine (slightly below max)
  • I don't think any brakes are binding, and car seems to drive fine
  • Tyre pressures seem fine

Are there any other things I can check, and any advice on improving the mpg?


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it depends somewhat on which cayenne you have (V6,V8,Turbo).

But those numbers are in the ball park for a V8/turbo.

I have a CTT, i get about 15mpg mixed, but in stop and go traffic, it goes way down like you had mentioned.

I've never seen 10mpg, but i have also never driven solely stop and go city traffic.

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Sorry, I should have made that clearer. It's a 2005 4.5 S tiptronic

The mpg's you guys have quoted of 15 and 17-18 - is that US or UK?

Us 15mpg 04 Ctt when I drive gingerly. my wife has heavy right foot 13mpg.

Remember it's a 5000 lb vehicle. It's not a prius

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Over the course of a fuel tank I average 19 UK MPG in the city using premium fuel and everything in proper working order. All tires set to 42 PSI. In perfect conditions on highway I can reach 26 MPG but average 22 MPG with wind/hills and such.

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I did a little experiment today and set all my tyres to 40psi (fronts were 35/36 and back were already 40). I reset the trip computer and it went up to 14-15mpg UK around town - admittedly the engine was already warm. Near our house it went down to 13.5 as it's quite hilly so that is probably another reason why it gets lower. I'm fine with those figures if it's normal, as long as there doesn't seem to be anything going wrong with the vehicle!

Is it ok to leave tyres at 40psi?

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I would say your MPG is accurate. I have a GTS and I often use it in Sport Mode and probably get a little less than 13 or 14. That's at least partly because it starts in D1 instead of D2.

Autobahn / Highway mileage has always been better than city in both the Cayennes that I've owned. HTH

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