I have it in one of my cars, but it displays only over 35 km/h, so you don't know anything under this speed
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Newer cars has the display at slower speed and has a hourly consumption under that minimal speed.
But the scangauge will brought you much more. My cars aren't SGII compatible, but the few times I could test it on other cars then I was surprised by how much the load can vary depending on your actions and the road changes.
Denis.
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