Poor MPG tried everything - need advice

[myfirstyota]

Is there 'winter gas' where you are? Apparently mileage goes down on that stuff.
Exhaust leaks can also cause a bit of a drop.

You didn't mention it but I assume it's covered in the general maintenance you did, air filter.

Also if there's a lot of short trip city driving, I don't get too far off what you're getting for mileage.

How's the terrain in your area? Hilly or flat?

Any extra weight on board? Ie. Unnecessarily full trunk? Weight kills these cars.