Honda: Gas Mileage, fuel mileage, wheels and tires

Question
Ray,
I have a 94 Honda Accord 4 cylinder 4 door sedan. I have 210,000 miles on it. Up until last year I got about 410-425 miles per tank. Now I am getting 325 to 350.   I change the oil every 3k, and the air filter every 15K.  I changed the plugs, wires, rotor and cap, last year.

I was told that I should change the Oxygen sensor. Do you have any advice on what minor things I can do to get my gas mileage back?

Thanks
Jeff

Answer
   Jeff,sorry about the delay,yes and maybe on the oxygen sensor.If the sensor is on the thresh-hold of going bad yet not bad enough to trigger the check engine light it can definetely cause poor fuel mileage but I'm not sure it would cause that much of a drop.When was your last valve adjustment? have you installed new wheels and tires?(rolling resistance)and then the main thing to consider..miles,as an engine wears it also looses efficiency and still run just fine.your problem could be any or all of the above,I hope this helps and again sorry about the delay.    Ray