Viewer-submitted questions for The Car Doctor ... We use Google Maps, and the GPS reading of my speed is about 3 mph different than the speedometer. Can you explain this? A.
"But wherever your car comes from, the speedometer still needs to be reasonably accurate, although it's unlikely to be as precise as your phone's GPS, which uses satellites to pin-point its position.
Some results have been hidden because they may be inaccessible to you
Show inaccessible results