About 27 highway, 16 and some change in the city. Mild driving style.

 

Glad to see some at what I'm now getting (17 mpg, due to is350 diff swap) I miss the mileage from stock but the car is a lot more fun with a lsd and stupid acceleration from gearing swap

 

15mpg is definitely not normal. I've averaged 21.5mpg over the last 5000 miles. This includes a lot of heavy-footed driving. Here is my Fuelly log:
http://www.fuelly.com/car/lexus/is_f...arnight/330598

My "mode" approach is pretty simple:

• General city driving < 55mph - normal mode, D
• Highway / interstate driving > 55mph - sport mode, D
• Curvy road / Hooning - sport mode, Manual

I find the car responds a lot better in Sport mode at highway speeds. You can ease into the throttle to accelerate without the need to downshift. I've noticed when I use normal mode on the highway, it has a tendency to downshift a lot more, and burn more gas.

 

^Sport mode has a sharper throttle map from what I've seen, so you don't press the pedal as hard compared to normal mode when requesting the same amount of torque. Too much throttle position and you downshift per the programming, which explains what you've experienced.

I get about 15mpg city and the only highway I do is rush hour. I'm rather throttle happy as well.

 

I've had my car about 6 weeks or so and have been averaging about 21mpg. Considering how I drive the car I think overall that's pretty damn good for the power of the F!

 

The guys at the dealership must of been having a lot of fun with it to get 7mpg

 

Must be common, mine was delivered with 7mpg average as well.

 

Happened to fill up today and took on a highway drive of 60 miles...average 27-28 if no AC, 26-27 with AC.75-80mph. This car has very decent highway mpg.

All local driving will get you close to 15-16 depending if the AC is on.

 

Just got the car 3 weeks ago. Sport and Manual mode, 40% city 60% highway = 22mpg. Driving conservative with a couple of short bursts a day.

 

grandma mode

 

I'm more impressed and envious at your gas prices. Such a drastic difference in comparison to CA's ridiculous price gouging these last few months.

As for myself, I average around 18 MPG city (60%), 24 highway (40%). I don't really use the different driving modes to help with gas economy. Almost all the time, I'm in SPORT mode and just do the necessary throttling to keep up with traffic

 

The tank is tiny. Really really tiny. Its annoying coming from an LS460 but have just gotten used to more stops at the gas station. Luckily I can at least get 5 days of driving with my commute

 

17gal is rather standard for a subcompact sedan.

 

I avg 25 highway, and 19 street.. Pretty reasonable if you ask me.

 

Yeah, our gas prices are very reasonable compared to CA. All my prices are Shell Premium (now Nitro+) as well. I never get the cheap stuff; top tier only