I tuned up my Civic cx and ever since unless I'm drugged the car is getting way worse fuel mileage. I replaced the fuel filter, plugs and distributor cap (screw is stripped on rotor, I'm working on it.) I commute 160 miles per day so I really notice the difference in fuel consumption. Could the problem be a bad filter? The car seems to be running fine, doesn't hesitate or anything and no smell of fuel. Any suggestions? I'm thinking I should try another filter? Thanks.