I have a Honda Vezel, which is available only in Japan. The closest (very close) equivalent is the 2016 Honda HRV.
It has a 1.5 i-VTEC engine (whatever that means) and a CVT gearbox. The shift has three forward positions: L, S and D.
I get an average 16.0km/l (37.63mpg) over a very long (>1 year) instrumented period of city only driving with highways of no longer than 10 miles. The car is relatively little used, only 28,000km in 4 years 10 months, or about 6,000km per year.
I think I have taken very good care of the car. After starting, I don't move off until the blue (cold) light goes off. This means a wait of up to three minutes every time.
My engine speed very rarely goes above 2,000rpm. On the highway at 80kph (50mph), the engine is just above 1,500rpm. The speedometer has a circular "eco ring", which is a light circling the meter rim that changes from white to shades of green when instantaneous petrol consumption goes from not economical to economical to very economical. Basically, it is green for me for all my journeys except during those short durations when I am accelerating.
To my surprise, now, after starting my car and warming up fully, the engine starts to jerk with resistance when I want to move off. It feels like my old car in the 1980's that had a cold engine. So far, although the engine feels like stalling, it has not stalled once as I ease off the acceleration when this happens. After driving for a few hundred meters, the effect disappears, only to return the next time I start my engine.
I brought the car to a workshop. The mechanic said there was nothing wrong and he didn't want to make money from me. He asked me to take the car onto the highway and keep the shift in S or L while at 50mph to "get rid of the carbon".
I did just that, and though it was painful to my heart, the problem disappeared after a 10-mile journey in S!
Is driving carefully or economically really bad for the engine?
