poor mileage??

[SoCalBMW]

I just calculated that my 95 318is got 26.5 mpg's on the last tank of gas.. 85% was freeway driving. It seems like I should be getting a lot better mileage... my car is pretty much bone stock. Is this normal or could there be something wrong?

[yeuchau]

325 will get that if it's 85% freeway

is your filter clean, and how about the tire pressure

[jrward]

run some fuel system cleaner (good stuff) and if you really desire a little more, 02 sensor will help, but they are kinda pricy

[SoCalBMW]

I bought some seafoam, Ill "hotsoak" my engine this weekend, tire pressure is always good.. Air filter is good. When should the 02 sensor be replaced? My car has 145k on it.