I have a 2000 150 with the 5.4, and my gas mileage has dropped from 15.5 in town in November, to 12.9 last week. The fuel filter was changed in June. I am not sure what is causing the sudden decrease in mpg. Is anybody else having the same problem.

 

my gas mileage always goes from bad to horrible in the winter.

 

Cold weather and ethanol in the fuel.

 

I have an 05 5.4 ... it did the same thing for the first time this year.. just like somebody turned a switch.. changed filter , cleaned injectors ..reflashed.. no improvement. so It may be the ethenol or the winter blend even though i live in Florida.

 

How much do you let it warm up in the morning? Idle with heater on etc?

Most vehicles get the best gas milage at 65 degrees, cruise control on at 46 mph

Move to northern Florida, and drive slow

 

after ported intake and the 93 oct tune on did on pats truck hes gettin 23.5-24mpg highway.