Mercury 1996 Sable Manual page 294

Fuel quality
Ford approves the use of gasolines, including
those reformulated, that contain oxygenates such
as ethanol (10% maximum) and MTBE (15%
maximum). If methanol is used, the gasoline
should contain no more than 5% with
cosolvents.
If you are experiencing starting, rough idle or
hesitation problems, try a different brand of fuel.
If the condition persists, see your dealer or a
qualified service technician.
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