My Firefly seemed to run just fine on 7 year-old gas when I bought it.
(However, I immediately drained and replaced it with fresh fuel anyway.)
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Refinery maintenance appears to be having the expected outcome, and then some: U.S.
gasoline inventories said to have dropped more last week than any week in the past 2 years.
EDIT: now they're saying the gasoline reserve decline is the largest since 2011.