I have a Silver 2008 Focus SES, it has 78,000 miles on it, and gets about 31 mpg...is there any way i can alter anything on my car to make it get better gas mileage? All my miles are highway miles, and I just cant figure out why my mileage isnt better. I use Shell gas station v-power fuel, its got fuel injector cleaner and everything in it. ahhhhh! someone please help me!