Salams
Usually the poorer fuel consumption can have several reasons, firstly being very heavy foot/ brisk accelerations, lots of stationary idle with AC on etc. Very slow moving heavy traffic use etc. Too big or too heavy tyres, very low tyre pressures increase consumption as well. Use of thicker engine oil, clogged air filter, old or wrong spark plugs all contribute. Finally the IMA battery, if it has become weak than that may be the reason. One can only go step wise and correct any/all issues and see how it will improve the consumption.
I can only describe my experience / use of my Fit. Bought my fit back in 2015 at 28000km, first owner in Pak, now driven approx 104000km. I had initially used fully synthetic oil 5w-30 oil, till 80000km, now I am using 0W-20 synthetic oil. Others may find it odd, but since the very beginning, I have always used fully synthetic oil, and used for 10000km before each oil change. Change my oil filter at the same time. Air filter Honda, changed at 20000km, if Leppon than 10000km. I put on Michelin Energy 185/65R15 tyres since beginning, on 2nd set now. Front pressure 32psi, rear 31psi. Car still on original plugs. probably will change next service time at 110000km. Drive with a moderate foot, the brake pads/shoes both front and rear are still the same ones from Japan, serviced at 100000 and mechanic reassured will do another 20k easily! CVT oil changed twice so far, indicator changing comes up on display (hmmf).
12 volt batteries changed twice in last 6 years Exide maintenance free battery.
The IMA module developed some fault 2 years ago, the IMA light came up on dash and module was replaced and have been fine since.
The car has been 100% reliable otherwise, never once failed to start or drive.
Fuel average best in spring and autumn, when AC and heater not used. Car used in Islamabad and so its fuel consumption may be better compared to cities with busier traffic.
Realistic summer fuel average has been approx 15-16kmpl in summers, the car meter may show 17-18, but I always calculate with fuel top-ups. Winters may be 17ish with heater regular use. And 19 in autumn / spring. Remember car meter always shows upto 2kmpl better than real figure.
Motorway M2 with cruise locked at 110kmph, and occasional push upto 130kmph, it gives 17kmpl in summer 18kmpl in winter, tested 10+ times.
