Left Hyun dry
I have a new Hyundai i30 1.4 petrol and have covered just 1,300 miles, but I am disappointed at the amount of fuel I am using. I have calculated my mpg to be no more than 32mpg based on the litres/gallons put in the tank versus the total mileage to date. I live in a rural location so most of my driving is steady rather than the stop-start of typical town driving. The "Average MPG" trip computer is showing a much higher figure but seems to fluctuate so rapidly at times, sometimes showing over 60 mpg, that I am concerned about its accuracy. What is the most accurate way of calculating mpg and how much faith should one put in the trip computer of the vehicle. So, how accurate are these trip computers and what is the most accurate way of calculating mpg?
Asked on 19 June 2010 by DP, via email
Answered by
Honest John
Fill the tank to the brim and write down the mileage on the back of the
receipt. Keep it. After at least 200 miles, fill the tank to the brim again and again write down the mileage on the 2nd ticket. Subtract mileage on ticket 1 from mileage on ticket 2. Multiply the litres on ticket 2 by 0.22. Divide the mileage by the result. That will give you the true mpg, assuming the car's odometer is reasonably accurate. The more you repeat this (keep a book), the more accurate the figure will be.
receipt. Keep it. After at least 200 miles, fill the tank to the brim again and again write down the mileage on the 2nd ticket. Subtract mileage on ticket 1 from mileage on ticket 2. Multiply the litres on ticket 2 by 0.22. Divide the mileage by the result. That will give you the true mpg, assuming the car's odometer is reasonably accurate. The more you repeat this (keep a book), the more accurate the figure will be.
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Real MPG enables you to register the fuel economy you are actually getting against your make and model of car, its engine and type of transmission.
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