I did a tune up expecting that my mileage would go up. ( spark plugs air and fuel filter
Maf cleaning fuel pump and injector .....) and my mpg still the same. Im doing 9 -- 12.7 mpg with a lot of stop and go and after every speed bump i smash the gaz pedal to feel the v8 . 4.4 2001 ( all the time in s mode) what do u think