I've had my car going at 45 mpg the past 2 years. I just hit my 45k mileage mark. I drive mostly on the highway to work so getting 45 mpg is pretty good for me. This last few fill ups, I noticed my gas mileage has gone down to 40 mpg. I thought it was a mistake if it was just once but the last 7 fill ups has been that way. It just went down all of a sudden and has stayed that way? Any idea what could have happened and how I can fix this?
Tire pressure perhaps. Check the vent in the rear floorboard and make sure it isn't being blocked. Check the exhaust port in the trunk area and make sure you have nothing in the space between the seat and the rear trunk mat.
