Most recently answered speedometer questions
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My Garmin nüvi 1300T satnav consistently shows 4mph less than the speedometer reading on my Qashqai 1.6 Acenta manual, checked on a level road. For example, at 30mph on the speedo the satnav reads 26mph....
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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...
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As my car's indicated speed differs by over 3mph on its speedo from what is shown on my satnav (which means there is at least a 10 per cent difference at 30mph), do you know which is more accurate? Also,...
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Is there a law which says speedos are not to under-read?
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I notice in most cars a satnav always seems to indicate a vehicle speed 2 or 3 mph less than the car speedo. I assume that the satnav should be absolutely accurate, but would appreciate your comments.
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I have a Ford Focus estate with a 1.8 Zetec engine, registered in 2001. It has now travelled about 75,000 miles with no problems. Recently a fault has developed: the speedo and milometer stopped working...
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I've just bought a new 61-plate Toyota Prius which has a completely electronic dashboard display. Checking the speedo against a SatNav, it showed that at a constant 70mph indicated (held by cruise control...
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I have a 2000 Ford Focus 1.8.
When the engine has warmed up the speedo stops working for 5-20 miles, while the speedo isn't working the odometer and radio don't work properly and the engine loses power.
Also,...
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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...
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You may recall my email of May 2010 when you advised me I could not reject a new vehicle for what I thought was a speedometer that over reads by 10 per cent. I have now received confirmation from the MD...
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