My Honda City

It has been some time since I shared on my car fuel consumption performance. I have device a new method of computing the fuel consumption. What I do now is to pump a fix value each time, in this case, I always pump 26.04 liter. This value is based on RM50 @ RM1.92/Liter. For each of the fueling instances on the x-axis, I pump 26.04 liter and drive the car till it’s empty, which is till the light comes up and the indicator go to the lowest, most of the time hitting E and below. Then I pump 26.04 liter again. I find that by doing this, the fuel consumption are pretty stable at the average of 14.5km/liter and a Standard Deviation of 0.59. My stock tires which are Goodyear RCT are going bald and I will be changing them soon. Currently I am eyeing on Continental Contact 2 or Michelin Preceda 2. The Tires manufacturer always claim that their tires safe fuel, etc.. well, I will be putting them to the test. I will compare the fuel consumption before and after the tire change. Since I will be changing all 4 tires at one go, it would be a good estimate to see if what the manufacturers claim are valid. Oh, by the way, instance 2 and 3 was Caltex Techron and the rest were Shell Super.

Petrol: Shell Super
Location: Juru
Liter Filled: 39.79 liter
Distance Traveled: 618.2 km
Onboard Computer KM/Liter: 15.5 km/liter
Manually Computed KM/Liter: 15.1 km/liter
City Driving: 30%
Hwy Driving: 70%

Petrol: Shell Super
Location: Penang Road
Liter Filled: 36.97 liter
Distance Traveled: 621.9 km
Onboard Computer KM/Liter: 15.5 km/liter
Manually Computed KM/Liter: 16.8 km/liter
City Driving: 40%
Hwy Driving: 60%

Again, the KM/Liter differs between the onboard computer and manual computation. Using back the old computing method, the onboard computer is quite close to the manual computation method. Now the question is, which computation method should I continue to use?

Petrol: Shell Super
Location: North South Hwy, Juru
Liter Filled: 37.87 liter
Distance Traveled: 577.8 km
Onboard Computer KM/Liter: 14.2 km/liter
Manually Computed KM/Liter: 15.3 km/liter
City Driving: 50%
Hwy Driving: 50%

KM/Liter improves after 10km service.

Petrol: Shell Super
Location: Jetty, Penang
Liter Filled: 37.31 liter
Distance Traveled: 519.4 km
Onboard Computer KM/Liter: 14.6 km/liter
Manually Computed KM/Liter: 13.9 km/liter
City Driving: 50%
Hwy Driving: 50%