Is the MPG reading under the RPM's usually accurate?
 

Last weel my MPG read 19.9, now 19.3. From what I can tell I get worse mileage than it states. One full tank only gets around 250 miles. Could this be an 02 sensor problem?

no , if you want to have more accurate MPG measurements, calculate your self, fill up a tank and take the total traveled miles of that tank and divide it by gallons consumed.

Mine typically shows 4-5 mpg high all the time.

The gauge is very optimistic. You can use it as a reference but don't rely on the actual numbers.

I always subtract 3mpg from the computer readout

Mine has always shown right around 30mpg (never reset) which is way off from the calculated average of around 25mpg.

I think mine usually shows around 19.8 2002 6 speed

Yeesh! I have the same exact car and mine registers around 25-27.

I drive it hard, I pretty much floor it every time I leave a stop sign or red light lol.

I hope you don't mind my 2cents but also you should also do at-least 3 or 4 tanks to adjust for different driving conditions. Unless you only go the same places every day. also if you don't buy your gas at the same place every time(which is what I recommend when possible) gas mileage can vary by several numbers. When I calculate mileage for a new car I do 3 or 4 tanks then wait a couple of weeks and do another 3 or 4 tanks. just my humble Bipolar opinion.:wall:

And that is roughly what I am getting. They are supposed to get 20mpg city, I always use Redline oil and change it regularly. Any Idea why our cars are not getting the alleged 20?

you guys must need a tune up lol!! On the highway back roads doing 55-60mph my car read 34mpg i was like wow lol. Premium gas, new knock sensor, new radiator, and new coils, new spark plugs, ect!