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Old 12-15-2008, 08:25 PM   #32 (permalink)
FastPlastic
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Join Date: May 2008
Location: Ames, IA
Posts: 419

98 Cherokee - '98 Jeep Cherokee
90 day: 17.18 mpg (US)

ZX7R Ninja - '99 Kawasaki ZX7R Ninja
90 day: 42.45 mpg (US)
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Quote:
Originally Posted by PaleMelanesian View Post
Both ethanol and winter-blend rfg have lower energy content than summer gas, with more oxygenates. Both together is a double hit. Since the Scangauge only measures airflow, it doesn't know that the ECU is adding a little more fuel to the mix to make up the difference. You need to INCREASE the fuel offset % to account for this. (ie. without adjusting, it reads higher mpg than reality)
That makes sense to me. The problem is my scan gauge was reading 1mpg lower then the final calculation at the pump(ie. the scangauge thought I had used more fuel then I did).
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