Jon, 3K RPM's is too high for 70mph in a 3.0L V6 Accord. My 2000 V6 Accord runs between 2500-2600 RPMs at 70mph. My gas mileage is about 29 mpg on the freeway (70-75 mph). My combined mileage is about 26.5mpg.

First - I would check your distributor cap. Then I would check your timing. When did you last have your timing belt changed? Is the car running very sluggage?

Doug