I have a 2014 Toyota Sai (Japan import, similar to a camary) with 54,000kms (33,554 miles) on it.

It’s getting around 16km/L (37.6mpg) where as other people with the same car are getting around 20-22km/L (47-51mpg)

I got the battery tested by a mechanic and he said all the cells are healthy and deliver the correct voltage. I’ve also inflated the tyres to the correct pressure. Is there anything else I should be doing or checking to improve the fuel efficiency?

Thank you so much!