mgp123 wrote:I have noticed that every 50miles the economy goes up.1mpg
Okay, this makes me suspicious. Have you ever reset the mileage computer? It could be that you're looking at the average mpg for the entire life of the car. With the average mpg displayed, pull and hold the display button until it resets, then see what you're getting. Or figure it out the old fashioned way, divide miles driven that tank by gallons used to refill.
mgp123 wrote:I'm still hoping for the rated 30mpg. Will have to increase the psi to 38. And take my Durango tools out of the trunk =/
The Durango was getting 14.5mpg. But that was what it was rated at. I hope car max didn't lie about the Kizashi's mpg,
CarMax didn't lie about anything, well, at least not about mileage. They just told you what the EPA and Suzuki rated the car for, mostly the EPA. Put 40 psi in, winter's coming, and take any unnecessary items out of the car to save weight. Although weight won't make much difference at all on the highway. 95% highway you should be able to get 30 mpg easy, unless highway means 90 mph to you.
Just yesterday, I filled up my tank then set out on a 60 mile highway trip, forgot to reset the computer until I was out on I-95 going 70 mph on cruise control. When I got off the highway 50 some miles later, it was showing 38.5 mpg. Obviously, that dropped as soon as I got off and started dealing with lights and such. Also, the mileage computer is a bit optimistic, but we're talking at least 35 mpg at pure cruise. Strange thing is, on the way back with the headlights on, it only showed 36 mpg. I wouldn't have thought the lights made that much difference, but it was only about 5° cooler, and there was no elevation component to consider, so that's the only significant difference I can think of. Actually, my beer cooler was only half as full on the way back, so there was a weight savings.

Need to do some experimenting to see if it's really the headlights sucking up that much power, doesn't seem likely to me.