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Speedo accuracy Vs GPS
With all the technical wizardry in modern cars, why do speedometers routinely over read? I've used GPS/Satnav units in many different cars and the cars speedo is always over reading. Spookily this over reading is normally very close to the permitted 10%.
Surely this is having a huge impact on the cars milage reading, and also any fuel consumption figures? Higher recorded milage means more trips to the garage for servicing, and more perceived miles means lower fuel consumption figures. All good for the dealers then?
Surely this is having a huge impact on the cars milage reading, and also any fuel consumption figures? Higher recorded milage means more trips to the garage for servicing, and more perceived miles means lower fuel consumption figures. All good for the dealers then?
Asked on 25 July 2011 by seadog101
Answered by
Honest John
They are deliberately set to over-read because up to 10% over is allowed, but no under-reading at all. Makes owners thing they are getting 10% better mpg than they really are, yet their cars are clocking up more miles.
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