I have a City 2011 which is driven around 2500km. I recently changed its oil + filter and went to Lahore via motorway. Even though I tried my absolute best, drove at only 110-120km/h I got only 15km/L with AC. When I was about to reach Lahore the tank was almost empty.
Then when I came back, again I got max 15km/L and this time I refueled the car at Bhera just in case. I didn't drive like a maniac, and kept the speed constant as much as possible. 15KM/L is what I get in Islamabad, on motorway I expect around 18-19km/L
I use 195/60/R15 tyres which does not change the height of the car so they're not the issue. What else can it be?