This study evaluated research conducted on the effects of E15 on Model Year 2001 and newer cars, and drew objective conclusions based on the entire available dataset (to 2013). Several of the studies tested relatively large numbers of engines or vehicles, finding no evidence of deterioration in engine durability or maintenance issues for E15 (or E20) in comparison to E0 and E10 (when tested). Materials compatibility testing provided no evidence that 15 volume percent ethanol blends will cause increased rates of metal corrosion in comparison to 10 percent blends. In most cases increasing ethanol content from 10 to 15 volume percent had no significant effect on elastomer swell. For 2001 and newer cars emission studies also show that engine control units are able to adequately compensate for the higher oxygen and lower energy content of E15. The engine performance and durability expectations from the materials compatibility and emission test results were confirmed by studies of fuel system, engine, and whole vehicle durability.

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Screencap - Review and Evaluation of Studies on the Use of E15 in Light-Duty Vehicles