On every car I've ever owned, my fuel economy drops sharply by about 4 MPG around October/November and it jumps back up around March/April. Does anyone know what causes this?
2003 Mustang GT 5-Speed, FMS 4.10 gears, Dr. Gas O/R X-pipe, Flowmaster cat-back, BBK CAI, C&L intake plenum, Accufab 75mm TB, Steeda Timing Adjuster -
13.70@102.23
(SOLD) 2000 Cougar V6 ATX with many mods -
15.93@86.97
