[StangFire]

I have a 05 V6 Mustang, with a K&N air filter. This is the only thing that I have changed at this point. I have had the K&N for about a year. The past couple of months I have noticed that when I fill up my car does not get the gas mileage that I was getting when I got the car. At first I was getting about 320 miles to the tank, now I am getting about 270 miles. I have cleaned the butterfly to make sure that there is nothing sticking from oil off the K&N filter. Other than that the car is running fine. Is there anything that can help with this issue.

[Tominator]

Winter means a special fuel formulation that is different than what we put in our tanks during the summer.

You will get 2 to 3 fewer miles per gallon because of this.



On a related note, the only way to properly document the actual MPG is by keeping records.

[jacutis1]

Also, be sure to check your tire pressure. During the summer months, I run great gas mileage, but in the winter I lose about 20 - 30 MPG/tank because my stock tires lose a $hit load of air pressure. All 4 tires lose about 5 - 10 PSI. Ford recommends 34 PSI. During the winter, I run an even 35psi and that levels it out pretty well. During the summer, I drop it down to about 32 as the air expands during the summer. Let me know if this helps.

[stlwagon]

I would not rely on the car's computer to calculate MPG.