Fuel efficiency of 2000 Sonata GL?

How many miles per gallon is this (4 cyl) car supposed to get?

I just bought a used 2000 Sonata and filled the tank with highest octane
available at Esso.
I've gone through a 1/4 tank in what seems to me to be a very short time
without driving very much.

On some cars the gas tank level inicators are not real accurate. They go
down faster the less gas there is in the tank. Is the gas gauge on the
Sonata known to be a little finicky in any way?

I've had the car inspected twice for service recommendations and have
done all the recommended things. Are there ways to tune this car up to
get better mileage?

 

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US specs (4cyl/auto) are 20mpg city and 27 highway (23
combined). Of course, this isn't REAL driving, only dyno. And
the faux mix (city/hwy) may not mirror your usage. Another thought:
my old Ford with the AOD trans quit going into fourth gear. Never
paid much attention until the fuel bill jumped. Checked the milage
and was getting around eleven to the gallon. Among other things,
the US$2000 for a rebuilt tranny made the decision to get a new
Santa Fe MUCH easier. =;-)

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I don't think it calls for the higher octane.

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You need to go through several tankfulls, keep a total mileage
record and fuel usage, before you can get a good handle on the
mpg. For instance, I've got 28,815 miles on my '02 Santa Fe
and put 1346.6 US gallons in the tank. Doesn't matter if the tank
didn't get to the tippy top on any given day. The multiple fillups
give me an accurate (IMHO) figure of 21.4 mpg.

S25

 

Yeah it turns out to have about the same milage as the 1987 Buick
Century I traded in on it. I thought the new car would be much better
but i guess my old beast was pretty good in the 1st place.

 

I have the 2.5L v6 and it gets 22-25 in normal driving.. just fill up the
tank, hit the trip odometer, then see how many gallons it takes to fil
lthe car up next time. Miles you drove/gallons = MPG