I was getting 27-28 mpg highway three years ago but now even being very conscious
of driving with a gentle foot , I can barely muster 23.5 .
The car is in an excellent state of tune with new O2 sensors , plugs , Air filter , ect, ect.
And the car see's fuel system cleaner on a regular basis.
Do you think this Ethanol fuel "E-10" is making that much difference ?
The car only has 114,000 miles on it.
And yes I've tried different tires just to check that aspect.