Mercury 1999 Villager - Manual (Page 219)

Octane recommendations
Your vehicle is designed to use
“Regular” unleaded gasoline with an
(R+M)/2 octane rating of 87. We do
not recommend the use of gasolines
labeled as “Regular” that are sold
with octane ratings of 86 or lower in high altitude areas.
Do not be concerned if your engine sometimes knocks lightly. However, if
it knocks heavily under most driving conditions while you are using fuel
with the recommended octane rating, see your dealer or a qualified
service technician to prevent any engine damage.
Fuel quality
If you are experiencing starting, rough idle or hesitation driveability
problems during a cold start, try a different brand of “Regular” unleaded
gasoline. “Premium” unleaded gasoline is not recommended (particularly
in the United States) because it may cause these problems to become
more pronounced. If the problems persist, see your dealer or a qualified
service technician.
It should not be necessary to add any aftermarket products to your fuel
tank if you continue to use a high quality fuel. Aftermarket products
could cause damage the fuel system. Repairs to correct the effects of
using a aftermarket product in your fuel may not be covered by your
warranty.
Many of the world’s automakers issued the World-wide Fuel Charter that
recommends gasoline specifications to provide improved performance
and emission control system protection for your vehicle. Gasolines that
meet the World-wide Fuel Charter should be used when available.
Cleaner air
Ford approves the use of reformulated “cleaner-burning” gasolines to
improve air quality. These gasolines may contain oxygenates up to 10%
ethanol or 15% MTBE.
Running out of fuel
Avoid running out of fuel because this situation may have an adverse
affect on powertrain components.
87
(R+M)/2 METHOD
Maintenance and care
219