First 1500 Miles With 1.4tfsi Cod S-tronic

[glospete]

My brim to brim figures for a journey from Devon to Cannock was 52.0 there and 49.8 back. Those journeys of 160 miles each way were almost all motorway (perhaps 25 on minor roads) and the ACC was set to 65mph on the motorway. I did read once that the difference in fuel consumption between 60mph and 70 is rather surprising, and 80mph will see your consumption rocket.
My long term average since getting the car is 43.7mpg.

 

[CaesarBob]

Interesting stuff, maybe my average isn't that far behind given the majority of my journeys are motorways 70+ (traffic dependent) and little town driving.

Back up North tonight so will see what i achieve with some restraint.

 

[glospete]

I found this which is the sort of thing I was looking for. If you go to their website you can input your own figures to see the effect of speed on your fuel consumption. Also an engine that has only done 1000-5000 miles will still be tight and not be returning the best economy. Often it takes many thousands of miles to get to the best figures.

http://www.mpgforspeed.com

As you can see a car is using 23% more fuel at 75mph than at 55mph, and 28% more at 80mph.

Speed Kills MPG
Unfortunately, it's true. Your car's gas mileage decreases once it gets past its optimal speed. For most cars, this is around 55-60 mph. This means that every time you go over this speed, you're essentially wasting gas and money - and creating unnecessary greenhouse gases.

You'd be surprised to learn that a slight decrease in your highway driving speed can significantly reduce your gas consumption, while only adding a few minutes to your travel time.

How much?
According to studies backed by the department of energy, the average car will be at its advertised MPG at 55 mph. But as the speed increases:

- 3% less efficient at 60 mph
- 8% less efficient at 65 mph
- 17% less efficient at 70 mph
- 23% less efficient at 75 mph
- 28% less efficient at 80 mph

 

[Stephen C]

Does 2-cylinder mode not activate with cruise control? I never saw it show up when cruising between 50 and 60.

 

[glospete]

I think it does but never actually checked. It certainly switches on even at 70mph on a light throttle.

 

[andyv49]

It does activate with cruise control on but usually not for long unless on a very flat stretch of road

 

[CaesarBob]

Well, made it back home with some interesting findings!

110miles of M5/M6 with the ACC set at 67.5mph. Average consumption on DIS 53.4mpg
Then, 55miles of A-road through Peak District and some heavy footed-ness ended at 50.8mpg

So, it is possible, but very much speed dependent!

Also, interesting to note it will run on 2 cylinders for quite a few miles at a time assuming it's flat/gentle gradients. It doesn't always seem that way though as it only displays on certain screens of the DIS.