Unfortunately, it is true. You may not notice it but that doesn't mean its not happening. Think about it, you need 30% more ethanol than gasoline to maintain the same air fuel ratio. When you add 10% of ethanol to gas the computer has to add 3% more total fuel through the injectors to compensate for the 10% in ethanol. We have tested cars on the dyno from 10% ethanol to 90% ethanol for a special project that we have been working on.