Mechanics

PETROL CONSUMPTION TOO HIGH

2007 Daihatsu Mira • 18,000 miles

Dear Expert,

I have bought MIRA 2007 a month back, second hand, showing 17000 mileage. Over all the car is bumper to bumper genuine and engine condition is excellent, drive is v. Smooth too. But the basic for buying it was for good petrol consumption (i heard it's between 15-17 km/ltr).

It is giving me 9 km/ltr with AC. I have changed it's oil (shell havoline), oil filter, cleaned the air filter (as it was already in good state), plugs are in v. Good state, engine throttle also. Still the mileage is 9-10 km/ltr on AC in city. I usually drive below 80 kms/hr and use empty roads.

Looking for a possible solution
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Fast_mani
June 7, 2012.




Are you using premium fuel, if not you will get better power and economy this way, also a scan will show up any unresolved electrical faults.

Mhpautos
Jun 7, 2012.
Yes I am using premium fuel. I have also octane available but never used. Secondly can you explain what do you mean by scan?

Thanks for the quick response

Tiny
Fast_mani
Jun 7, 2012.
A scan can be done by most mechanics, this checked for any problem in the engine management system.

Mhpautos
Jun 7, 2012.
Can you name any expected electric faults which could have been the reason for low consumption of fuel? I have checked the plugs they are like new. Further premium is ok as fuel?

Thanks.
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Tiny
Fast_mani
Jun 7, 2012.
What method did you use to measure the mileage consumption?

KHLow2008
Jun 7, 2012.
I drove under 80 km/h with D4 gear and with A.C. There is only one traffic signal in my way to office, which is of 1 minute, I put 10 ltrs of petrol when tank has one light, and after 102 km the one light signal was there again.

I have normal tyre, no alloy rims etc

Tiny
Fast_mani
Jun 7, 2012.
The low fuel warning indicator is not a very correct guage for fuel consumption. You should fill up to full tank and after driving a certain distance, top up again and check how much you have used up for the mileage.

Did you perform the test in one complete run?
If you are doing short distances and driving time per day, it is not an accurate gauge.
You mentioned the mileage in miles and you are calculating in km, is that correct?

KHLow2008
Jun 7, 2012.
Hmmmm actually I have used the low indicator criter for atleast 5 times and every time it has not given me above 10 ltr/km. Sorry everything is in km (miles was just a mistake). My test is not in one complete run, it's actually office to home and home to office which is around 40 km in total

Do you think MIRA 600cc 2007 model has that much capacity to go to 15-17 km/ltr in city with ac, with normal driving style

Tiny
Fast_mani
Jun 8, 2012.
15 - 17 km/ltr is for general usage and solely for city driving, I don't think you are going to get it.

Driving 20 minutes or less per trip would reduce the mileage as the engine needs to warm up and this would have the engine running richer than normal due to the engine operating temperature.

Mileage claimed is only a general guide and test were performed under certain conditions etc and I would expect a difference of 10 to 15 % to that figure, and that is when running for a longer time and distance. Short trips are never accurate and there is nothing you can do to change it. It varies according to driving condition, speed, time and traffic condition.

KHLow2008
Jun 8, 2012.

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