When do most of you guys replace them? How do you know if you need a new one? Mine gas mileage isnt to great so i was told to replace my fuel filter. I have 67,000 miles and i am not sure if its been replaced ever. How much do they usually run?

 

I used a Purolator filter with my stock fuel system. Changed it evry 25K miles or so to play it safe... the factory doesn't even include a recommended change interval. I think the filters were about $15.... seemed high.

I would wonder how a clogged fuel filter would cause poor gas mileage, unleess its causing major misfires.... if anything, its going to cause it to run with inadequate fuel = lean = less fuel used. When an EFI engine starts to lose gas mileage, its usually something that causes the PCM to enrich the mixture when it isn't needed. Examples would include misfires, exhaust leaks before the O2 sensors, and faulty O2 sensors.