[Bac]

I’m trying to figure out the fuel consumption correction in the hidden menu.
E90 325i N52B25.

Before the trip, the tank showed:
10.7 (L) 20.8 (P) 31.5 (Total)

After the trip:
2.1 (L) 22.7 (P) 24.8 (Total)

Difference: 6.7 litres

Distance? 121.7 km 🙃

I’d maybe understand a result of 8–8.5. About 70% of the driving was on the motorway. 5.51 l/100 km is an unrealistic figure for a straight-six 2.5L.

It’s not even that I’m calculating it wrong — based on the distance and the tank readings, this is what comes out.

Does anyone know what’s going on?

EDIT: Yes, I've zeroed the odometer before starting the trip.