Ford 2005 Escape Owner's Manual page 263

If you do not use the proper fuel filler cap, excessive vacuum in
the fuel tank may damage the fuel system or cause the fuel cap
to disengage in a collision, which may result in possible personal injury.
Choosing the right fuel
Use only UNLEADED FUEL. The use of leaded fuel is prohibited by law
and could damage your vehicle.
Your vehicle was not designed to use fuel or fuel additives with metallic
compounds, including manganese-based additives. Studies indicate that
these additives can cause your vehicle's emission control system to
deteriorate more rapidly. In Canada, premium grade fuel generally
contains more metallic additives than regular fuel. We recommend using
regular grade fuel. In Canada, many fuels contain metallic additives, but
fuels free of such additives may be available; check with your local fuel
dealer.
Do not use fuel containing methanol. It can damage critical fuel system
components.
Repairs to correct the effects of using a fuel for which your vehicle was
not designed may not be covered by your warranty.
Octane recommendations
Your vehicle is designed to use
"Regular" unleaded gasoline with
pump (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, try a different brand of unleaded gasoline. "Premium"
unleaded gasoline is not recommended for vehicles designed to use
"Regular" unleaded gasoline because it may cause these problems to
become more pronounced. If the problems persist, see your dealer or a
qualified service technician.
2005 Escape (204)
Owners Guide (post-2002-fmt)
USA_English (fus)
Maintenance and Specifications
87
(R+M)/2 METHOD
263