I have taken multiple readings on my Accord and have had disappointing results. I have gotten anywhere from 20mpg up to 22mpg. A small 4cyl car should be getting much higher, right? I try to drive smoothly and use cruise control often so I have no idea what could be preventing me getting closer to 30mpg.
What mechanical items could be malfunctioning (or just not working well)?

 

You have to start with the basics, air filter, spark plugs, plug wires, dist. rotor, tire pressure.
Clean the throttle plate area with carb cleaner and a soft bristle brush [toothbrush]
Are you sure the trans [automatic???] is getting into lock up at highway speeds.
Brakes dragging, like a stuck caliper pin on the front calipers.
EGR stumble at light throttle [1500-2000 RPM] ??
Lots of red lights on the way to work each day?

 

I took it to the Honda dealer when I bought the car and they replaced much of what you mentioned. I got brand new Michelin tires so I wouldn't think it would have to do with the tires. What do you mean getting into lock? Like low RPMs? If I set it on cruise going 70mph I usually am around 3,000. I will look into some of the other things that you said. Thank you so much for your help!