My new 2016 CX5 is terrible on fuel

[Irenicus]

Just picked up a 2016 Mazda CX-5 GS AWD - thing is mint and has pretty low kms with 86,000km. Full maintenance records, inspection, drives clean, I did so much research before I bought this thing.

But it's dreadful on gas in the city. I don't understand why or how but it's significantly below what it should be getting. Highway MPG seems to be on par with what it should be getting. I drive VERY light. I'm trying to do a deep dive on things I can control. I just ran a tank with..

22% highway driving
78% city driving
and it was 12.3L/100km or 19.12MPG and it's rated for 24MPG with 100% city driving..

Stuff to do?

- Cleaning MAF sensor - haven't done this but will look into it
- Spark Plugs? It only has 86k on it, recommended changing at 120k..
- Air Filter - looks super clean
- Ultrasonic clean the Fuel Injectors maybe? My buddy suggested it
- Run 37-39psi on the tires. Spec says to run them at 34psi but this was recommended
- PCV Valve? no idea, buddy suggested to look into this
- Additives like seafoam or fuel stabilizer. Not sure if this would be worth it

Any suggestions are greatly appreciated. I love this thing but man I didn't realize it would have such dreadful consumption in town