I have a 1/2 dozen or so 100 mile fill ups at almost all being 15.3 mpg. Lots of idle warm up time, lots of right foot, running at 2k 2.5k. Last 100 mile fill up was about 10 mpg.....??? Differance,, less warm up, way less right foot, and 1.5k-2k rpm. Im going to run through another 100 miles...