I never an answer
Use it as the manufacturer of the product recommends and you should be fine. A better fuel treatment in my opinion is Techron by Chevron. Also to be used as the package instructions indicate.
You can also look around for a gas station that sells fuel that does not contain ethanol. I live in a coastal area and it is readily available (for boaters) in highway gas stops. If you can't conveniently find non-ethanol fuel then Star Tron, Techron or other additives are good if used as directed. Be sure to pick one that does not contain alcohol of any type.
Ethanol was not mentioned and really cause few issues. In many areas of the USA fuel without ethanol is difficult if not impossible to find.
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