Engine will start to consume more fuel after idling for more than 30 seconds.

If you pump full tank which means, your true FC is 360km/40l = 9km/l (Vios full tank is 42l, assuming you don't refill when your tank is totally dry), not sure if you can really pump 40l ngam ngam because sometimes the fuel lever will disengage once you pumped till 33-35l. So, optimistically, true FC is about 10.58km/l

11.7km/l is just the average FC with mixtures of many trips. If few trips drive a lot highway, the meter calculation
will give you a false sense of fuel efficiency.

I also have the assumption that you have just got your brand new car, so not sure about the mileage of your car. It's probably too early to tell now whether your car is having a good FC or not. If you practise good driving habits, for example, having light a foot, smooth acceleration/cruising at constant speeds, the ECU in your car should learn from your habits and it should become more fuel efficient over time. Also, some other factors to take note such as the weight of your car, right amount of tire pressure, regular car maintenance and necessary oil changes.

This post has been edited by geekster129: Aug 1 2014, 10:46 AM