I was just curious as to why we have such disparate observed initial values. I drove my Z practically off the truck. Had 4 miles on it when I drove it home. During the first several weeks, driving it as suggested in the manual, it had me at 16 mpg. After breakin, my mileage increased by 4mpg. I haven't obsessively tracked mine, so I'm wondering now if the ECU was wrong initially or if we were driving it just that differently.:confused:

I wonder the same thing. I will say that my car was driven 300 miles from another dealership before I took delivery. Im sure it wasnt driven gently then, so the gauge read the lowest I've ever seen it when i bought it. Did your mileage actually jump up after breakin or just gradually increase?

I typically drive pretty conservatively, and always have. I usually shift at 2200-2500 rpm or so, sometimes at 3000, very rarely any higher, except for autocross/track.

It was fairly gradual, but it was only a matter of weeks. I drove it pretty hard after break-in. Still do, but that wouldn't explain an increase. :)

I guess maybe we can chalk it up to different driving styles/habits and different roads/weather possibly. But the hard evidence you've presented makes me think my experience may be the exception, rather than the norm.

The average for the life of my car is 24.8 That is just what the car calculates(on that ugly silver screen on the left of the steering wheel). However, I have gotten 36 mpg on a tank(followed behind a tractor trailer for far too long to Louisiana)(pretty sure that was the most boring drive of my life), but the worst I have ever gotten is like 15. I am only 18 so I can't afford any tickets, especially not in this car, so I drive pretty safe for the most part.

For those who think the 36mpg is b.s., I have a video somewhere, I believe on my old iphone. The navigation in the car only reads up to 30, but after taking the miles divided by gallons, I came up with like 35.8 so roughly 36.

But like everyone has said, if you are worried about gas mileage you got the wrong car. I like to enjoy my car from 0-60 and then from there, we keep it legal.

going by the screen next to the steering wheel. I got 27 on the 200 mile trip home from the dealer on the interstate. On my commute to work with is 15 miles of high, stop sign, 15 miles of highway, 4 miles of town with 8 or so stop lights I and a couple trips to the bar and grocercry store a couple block from my house I average 21-23mpg.

I have found that I get better milage setting the cruise closer to 70 than at 65 or less.

Thanks guys, I guess i need to wait and put some more miles and see how my MPG changes

At first I was thinking how how bad all your mpg figures are, then I remembered there is a US gallon and an English gallon!

jpritche - Simota1 has a vinyl sticker to help with that!

Remember ... best not to use cruise control during the break in period. Your mileage will improve, but you didn't buy the car for gas mileage did you.

:iagree: cruise control is bad for break-in. You're not supposed to drive a constant speed for prolonged periods.

My MPGs went up briefly when I installed K&N drop-ins and a F.I. CBE. Then they went back down right away. Can't figure out why....

i get about 22-23mpg mixed highway and city, but truth be told i didnt even look at the EPA sticker when i bought the car. i just knew what i wanted

My little silver screen tells me I get 18.3. That is from the day I bought the car w 9 miles on it. Currently at just under 12,000. And I've only had the car for 6 months :tup: I bought my car to drive as u can see lol no garage queen here!! Best I ever got was 21 but I don't drive on the highway and idk what 1/4 throttle is ;)

~10mpg while on the track and average DD at 22.5 mpg

Now at 40k miles and has improved slightly over time and tuning

I average about 28mpg based on my calcs, about 29 according to the trip-meter.