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Anon

Earlier this year I asked you about the fuel efficiency of our new Hyundai Getz 1.4L auto (10 L/100k). The Dealer told me it would probably improve after 2,000-3,000km.

After 3,000km the fuel economy is still the same. The Dealer also thought this was not quite right considering the nature of trips and driving behaviour. They did test the car, but found everything in order.

They now recommend I try 95 octane petrol to see if the fuel economy improves. In their opinion the quality of the 91 petrol is not great in NZ.

Could the Dealer be right and should I accept this, as the manual tells me I should use 91?

Robert

From the "Ask Jack" archives - 25 September 2009

jbiddle

The Dealer is talking a load of rubbish about the fuel quality in NZ to be frank. Sure there may be better fuel in the world somewhere, but what is sold in NZ must meet a specific standard and is equal to most other countries.

It would be interesting to ask the Dealer just what exactly is wrong with the NZ fuel in comparison to other markets. I would bet money they couldn't tell you or produce any evidence to support their theories.

They are avoiding the issue by blaming something which is conveniently out of their control.

You may have to accept the fuel consumption you are achieving, but not their reasons why.

If the Dealer is satisfied there is nothing wrong with the cars engine management system then there can only be a couple of reasons for the fuel economy you are getting.

Firstly, if you only drive the car on short and cold runs then the consumption is never going to be brilliant. Even on the most fuel efficient cars such as the Toyota Prius Hybrid, the fuel consumption can be over 20L/100km's on a cold initial start. It can take up to 4-5 km's to warm the engine sufficiently and to start lean out the air / fuel mixture.

I'm not sure if the Getz has a instant fuel dash read-out but the next step would be to ensure your consumption figures are correct. I believe the best way to carry out a fuel consumption test is to fill the car completely (wait for the auto fill to click off wait 10 seconds and refill again), zero the odometer and drive the car for say 1 week / 200kms. Refill at the same station (and same pump if possible) and take a reading of the litres added and the distance travelled.

You can then work out the consumption from there. I would be happy to recheck your calculations if you provide me with the data.

The other big factor is the way the car is driven. Smooth throttle control is the key along with avoiding lots of cold, short and stop / start runs.

Hyundai have never been class leaders on fuel consumption with petrol engines, but I would have expected a better result from the Getz in normal driving conditions.

I'm surprised the Dealer does not offer to carry out a supervised fuel consumption test to confirm the actual fuel consumption.

The car I am currently driving on a daily basis (2.0 litre engine), regularly achieves around 7.5L/100km and I would have expected a similar or better result from the Getz.