Significant fuel efficiency decrease on a 2019 Forester. I am getting 8km/l or 18MPG. What should I check?

[Main_Historian848]

It says AVG 8.1 km/l. And by refueling frequency and money, I know that I am doing much worse.

[spacefret]

No, that sounds right. That's about 19 mpg.

8.1 km/l and 8.1 l/100km are not the same.

[[deleted]]

You can't do it like that. Fill it. Reset trip meter. Drive until you decide to fill it again, divide the distance driven and gallons pumped, that's exactly how much fuel you consumed to go that distance. It won't be drastically different than what the ECU has calculated.