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kswami74
By kswami74 | AA Member | 3 Posts | 9 February 2014 at 7:02pm

Hi,
I have a one year old Suzuki Swift RS and its board computer indicates its fuel average to be 16.5Km/L. However, I seem to consistently getting an actual fuel average between 13.3Km/L and 14.5Km/L. The actual is based on the trip odometer reading between refuels and the quantity of fuel filled in.

Suzuki NZ & the dealer say that this is as expected but I think that I should get a better than average reading sometimes! I would appreciate your opinion on this or is this as expected.

Thanks.

Anon
By Donavan | AA Expert | 1049 Posts | 10 February 2014 at 9:13am

The instantaneous fuel economy reading is for a particular time whereas the average fuel economy reading is taken for the distance travelled since the reading was last reset – motorway, city, etc combined driving.

The 1.4L RS fuel economy is rated at 6.2L 100km in a combined driving cycle and you are doing really well at 6.06L/100km (16.5km/L) which is even better than the claimed amount.

I cannot see a problem here and you are getting really good fuel economy readings.

kswami74
By kswami74 | AA Member | 3 Posts | 10 February 2014 at 10:52am

Hi, Donovan,

Thanks for your response.

The fuel economy reading values of 13.3Km/L to 14.5Km/L that I indicated are not instantaneous values. These are the actual averages that I have calculated based on the amount of fuel I put in the vehicle & the distance the vehicle has travelled between the re-fuels. I compute these everytime I re-fuel. I have been calculating the actual average for every re-fuel over the past 9 or months. I have never gotten an average that is close to the 16.2Km/L to 16.5Km/L that the on board computer indicates. Hence my earlier question/concern.

Thanks again for looking into this.

Anon
By Donavan | AA Expert | 1049 Posts | 10 February 2014 at 10:58am

These figures of actual and what the onboard computer states will never be identical. The onboard computer is a good guide but it relies on information from the injection computer, fuel gauge reading, etc to work out the fuel consumption.

kswami74
By kswami74 | AA Member | 3 Posts | 10 February 2014 at 3:43pm

So there is not much I can do apart from accepting the fact that the (new) car does not give the fuel economy that the manufacturer (and the on board computer) suggests? Surely this can't be the case.

Anon
By Donavan | AA Expert | 1049 Posts | 10 February 2014 at 4:14pm

The actual fuel economy results should be achievable under ideal conditions for this vehicle but it is dependent on weather, driving style, load in vehicle, etc. You need to ensure that you are accurate with your testing procedure; especially with the fuel level filled to (before and after) driving.

From a fuel economy test we previously carried out on the 1.4L Suzuki Swift we managed better than the claimed economy.