Well, I now have had my base F-Type for a year and I am one of those strange people who actual computes my mileage at each fill up. So after 7,786 miles and 338.74 gallons of gas, my F-Type averaged 22.99 miles per gallon, which is exactly what the window sticker said the car would average.

What I did find strange was that at EVERY fill up, the car's computer had over estimate my mileage by almost 2 mile per gallon. The only time is was a little more accurate, was when ALL the driving was highway and then is was off only about a mile per gallon.

I do wish Jag would program the computer to be a little more accurate. Both gas mileage and Speed are reported higher than actual. Yes the speedometer reports a higher speed than you are actually driving. In my car that is about 3 to 4 miles per hour!

 

Holy crap! That's not at all bad!

My bad boy is getting less than 14!!!!

 

If it were only mileage that were off, you could check to be sure you're set to US gallons, not imperial. But obviously, that doesn't explain the speedo being off. How have you checked it? I've found roadside speed radars to be way off - I use the mile markers on a highway, set the cruise control to 60MPH, and use a timer to get the time between markers.

 

We have had ours for 8 months and only 1,300 miles. We have run a few tests also and found 20+ mpg around town and 25 mpg on the highway. Average, yep, approx. 22-23 mpg!

I thought that was pretty good. I thought I'd try for the max on a trip. It was all freeway and I drove the car in "snow mode". We got 26.9 mpg. Now the car wasn't as fun to drive but just testing

 

I have tired changing the setting from US to Imperial and found that it really didn't make a difference. I am not sure if Jag really programed the computer for US and Imperial gal.

I have checked the speedo using both roadside radar and GPS. I know all European car are very conservative on the actual speed. This is because if driver is stopped for speeding and it is discovered the speedo showed that the car was going slower than it actually was the Manufacturer can face a very large fine. I have found all European made cars to overstate the speed by 2-3 or more miles per hours at an indicated 70. Most US made cars are almost dead on. I know that Motor Tend or some other mag had have articles about this.

 

That figure definitely suggests you're doing the calculation in US gallons - or you're having a lot of fun...

Given the difference in size between a US and an Imperial Gallon, it sounds as if the car is working on Imperial Gallons. Just a thought.

I think - legally - a speedometer can over read by 10% +4km/hr (2.49mph), but must never under read.

 

Quick check: Since delivery, has everyone else's fuel economy stayed constant, improved, or???

The reason I ask is that on the initial 33 mile drive home (slowly...) I only managed 15mpg (according to the car). Over the rest of the week it's been getting better, despite using more throttle, and keeping it in the lower gears.

It just passed 22mpg overall, indicating that it's doing quite a bit better now.

Only 200 miles so far.

 

I've only got a few thousand miles on the R.. just really busy and have not been able to get it out and enjoy it enough.
As a test, I held the speed to about 60 mph for a fairly long period of time and the computer showed 32 mpg... which I find hard to believe. When I get a chance I will work it up manually to see what it really is, likely on an extended trip.
Lawrence.

 

I just filled up and checked. The car said 15.2 mpg and actual was 12.74. Most miles were stop and go and I've been having fun.

 

If you're averaging ~20 mpg, you're driving the car wrong

 

On way back from work with a mixture of motorway (80%) and single carriageway roads, I averaged 32.9 mpg .. was amazed. And did not drive softly .... obviously need to try harder.

 

Please remember that the F-Type's computer overstates mileage. In my car it is about 2 mpg and about the same in my wife's S-Type. I assume that Jag does this on propose so we think the mileage is better than it actually is.

 

Or it could be doing the calculation based on Imperial Gallons.

 

Exactly...it's like buying the R for fuel economy,lol!