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Should I trust my Mondeo's trip counters or my own calculations when measuring mpg?
I have owned two cars from new with trip computers, both of which were over-optimistic about fuel consumption. Typically in my 2008 Mondeo diesel I achieve 47mpg by doing brim-to-brim calculations. The trip computer always eventually settles around 52-53mpg when my driving is mixed, including motorways and town driving. People often quote their car's mpg to me based on the trip computer but I am usually sceptical. Are some better than others?
Asked on 16 June 2012 by PJ, Altrincham
Answered by
Honest John
Your odometer might not be correct either. My Mazda 5 measured a regular trip I have to make as 294.5 miles. Others have measured it at as much as 312 miles. The average is 300 miles. On cruise control at 50 or at 70 I found myself overtaking other cars. So I conclude that the Mazda is closer to accurate than any other car I have driven, and I can't safely drive at 75-80 on the speedo using the standard margin for error.
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.
Every time you enter an average consumption figure against your car, the overall average automatically adjusts to reflect it.
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