Let’s discuss the other issue that was mentioned. A few people said that the hissing was normal, and it usually is in most circumstances.

We know the hissing noise is caused by a pressure differential between the fuel tank and atmosphere. When one unscrews the cap, the two pressures equalize, and if air is sucking INTO the tank when you unscrew the cap, THAT would be considered normal.

However, if pressurized fuel vapors are escaping OUT of the tank during pressure equalization, and THAT is what’s causing the hissing noise, then you have a problem with your emissions control system.

On my AT, I get 33 with plenty of highway commuting. If I use it to do some spirited runs it dips to 30 and once 28. Never seen 22.

Are those Imperial liters?

Stock tires?

Tires make a difference. I made an extreme change from the stock tires to sticky summer tires on 18x9.5 rims and immediately lost almost 20% off my fuel economy.

if you're driving a stick, low 20s is very normal if you are hooning around in the city. On average, I usually get about 23 mpg but I find that it pretty easy to achieve 30+ mpg if you are driving on the highway. Just the other day I drove out to a casino a couple hours away and when I checked my average after I got home it displayed 32 mpg (reset before the trip ofc). The best MPGs I got was when I had an automatic FRS though, it was pretty hard to dip below 25 mpgs even though I was usually in M mode lol

i dont think i've ever gotten below 24 mpg, i average 26mpg. Before the supercharger and before i switched out the prius tires it was an easy 30mpg cruising at 80 mph. 30 minute commute, about 10-15 minutes of it being city, the rest highway.

In 527 measurements (almost all near full tanks) my lowest has been 27.6MPG which included a couple of hours in a stop and go traffic jam due to a highway accident on a trip.

My best has been 40.51MPG which was on a roadtrip where I filled up right at the highway, drove 319 miles nonstop and filled up as soon as I got off the highway. At that rate, I could have gone another 200 miles before needing to fill up.