badornato

Just filled the fuel tank on my new to me 2017 ES350 with recent av fuel use about 25 mpg.

the "range" indicator reported on dash screen says 242 miles... that is not correct. 17 gal tank with 20 mpg would be 340 miles

is it something i am doing wrong?

Tootsall

You are not waiting long enough: when you first fill the tank the mpg is artificially low; the computer thinks you are going to drive the whole tank at low speed with the throttle more open giving low mileage. This is even more true in cooler weather when you may be "on the choke". Your computer is probably basing it's calculation on something like 18-20 mpg instead of the 25 average that you get. Ignore that range indicator until you get at least 1/4 of the way through a tank before it starts to become more reasonable. Even then, don't fully trust it: I always record volume from the pump and mileage from the odo to calculate my actual mileage and "forecast" my range (which I only consider on long highway trips...~400 miles or more). I use litres/100 km on mine and just after I fill up it will show 30 l/100 km when I know that I only use about 11 l/100 in town (even less than that in summer) and as low as 6.9 l/100 km on a warm summer highway cruise. Of course, there is also the issue that you probably have more fuel left in the tank than the gauge would lead you to believe. Keep a record until you "calibrate" yourself to the fuel indicator and your own personal driving style.

lesz

There are a couple of factors that could be affecting the estimated range.

First, the estimated range does not include use of the "reserve" portion of the fuel tank capacity. And the reserve accounts for roughly 3 gallons out of the approximate 17 gallon fuel tank capacity.

Also, the estimated range is based on the fuel economy history of the car over an extended period of time. If you are a new owner of the car and if the previous owner was driving the car in a less fuel efficient manner than the way you are driving it, the estimated range would be based mostly on the poorer fuel economy history of the previous owner of the vehicle. Over time and as you accumulate miles of driving the car, the estimated range should adjust to the fuel economy and driving habits that you are using.

august49

I’ve never had this problem on my 2018 ES350. Every time I fill up and drive about 50 feet, the range shows approximately 340 - 360 miles based on my previous average mpg.