I currently have my speedo set in kilometers, in which mode the momentary fuel consumption bar works in a more intuitive way - ie short is good, long is bad, albeit in litres per 100 km
If the engine is running, even when warm, mine consumes fuel at about the following rates. -
Slow engine speed , barely audible . typical for normal use when the engine needs to start to keep the battery topped up . about 5 litres per 100 km = 56 mpg
medium engine speed , engine audible - typical for a sudden brisk overtake, or climbing a fairly steep hill. 10 -12 litres per 100 km 28 mpg - 23 mpg.
High engine speed. Engine quite noisy. This is not common. Many drivers have yet to experience this. Only happens if you really put the pedal to the metal, 15 - 20 litres per 100 km 18 -14 mpg.
At first I was horrified to find that at times I was only getting 18 mpg . This concerned me more than any rise in noise level. But even conventional petrol and diesel cars have similarly high fuel consumption in these circumstances. They just lack the Jazz Hybrids ability to average this out against periods when they are using no fuel at all.
If you mostly do short trips from a cold start , or drive at motorways speeds, or drive 'enthusiastically, the engine will be running more often, guzzling petrol .With fewer periods when its using no fuel at all . Simples. The fuel consumption overall will be good, but not exceptional compared to some small conventional cars.
With mixed driving, I was once able to average 82 mpg over 500 miles , despite occasional bursts at only 18 mpg or less. I've posted that trip computer reading on the main mpg thread because " It took so long to bake it,and I'll never have that recipe again" (It was crossing the alps, not in Mac Arthur park
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