Don't worry,

I had avg of 17-21 mpg when I got my GS300 AWD and now I get avg of 25-30 mpg. It took about 5000 miles to improve considerable. Each tank will get better gas mileage over time. Thats a fact for all cars.

 

I get around 22mpg(city) and have around 1500 miles.

 

Only 18.9 mpg (40 City/60 highway) with 1200 miles. Maybe the engine really needs the break-in period, just hoping the gas mileage will get better.

 

Seems for me I'm always at 15-17. I did see 22-23 once or twice, but that's it. To be honest, I drive the car hard. I don't mean to, but I do. And there is a lot of stop and start driving around here.

 

We've done this test in the 1st gen IS forums including IS300.net aka my.IS several years ago. There was no benefit in fuel consumption using snow mode. It's all about your driving sty le and how far you dive into the accelerator pedal that counts the most.

 

I avg about 20.3-22.6mpg. My worst was about 18.8mpg, but this was all Los Angeles City driving. What is your tire pressure? Maybe that could contribute to the low mpgs.

 

I have 1500 miles on mine and am getting 19.5-21.5 in town driving for mileage. Hard to keep the foot out of that 3.5.

 

You guys dont have it that bad, it all depends on where you drive and how you drive. My gs300 consistently gets me 18.5ish according to the dash, I have a 7 mile commute that averages 20-23mph according to the trip computer, up and down a couple of steep hills....my old 04 4 cyl camry used to get 23 in the same route

 

Agree...

I am in about 5k on the clock now and my average per tank is 19-20 doing 30% city 50% highway 20% highway traffic jam
Yet, I do like to give my GS a little wake-ups, whenever I feel like it... getting well below 6 seconds on 0-60...
Hence under normal driving conditions average is about 22-23 mpg
15 mpg?
Maybe the first tank is the answer?
Car might be idled for a long period which unfortunately affects MPG reading on trip computer.

 

13.8 2day.

 

I wouldn't say so...
Theoretically PWR button will keep your RPMs higher and shift up later/shift down sooner, but in practice I've done for comparisson reasons 2 tanks on normal and 2 tanks on Power settings - same results, sometimes PWR even better... 19-20 mpg average...
Hence its a driving style issue the 3GS350 is very capable of doing very high 20s on freeway without touching accelerator and around 20 with aggressive driving competing with M5, 750 and S550 (all of those doing way below 15 mpg with agressive driving).

 

30+ mpg?
wow!
was your engine on?

 

The only time I got ~30MPG was when I had just filled it up and then jumped on a stretch of road with no traffic and cruised at 55MPH for about 15 miles. Mileage dropped down to 18MPG by the time I had burned through that tank of gas though

If I fill up and just do local driving, I get about 15 - 17 MPG just around the city.

 

Hey Iam getting 18-19mpg as I cruise around the city

 

I guess I have a similar driving style as you because that's just about what I average day in and day out.