Lincoln 2010 MKS Owner's Manual page 325

Note: A fuel spillage concern may occur if overfilling the fuel tank. Do
not overfill the tank to the point that the fuel is able to bypass the fuel
filler nozzle. The overfilled fuel may run down the drain located within
the fuel filler housing and to the ground.
If the Check Fuel Fill Inlet message comes on, the fuel fill inlet may not
have properly closed. The inlet may have stuck open or debris may be
preventing the inlet from fully closing. At the next opportunity, safely
pull off the road, turn off the engine, open the fuel filler door and
remove any visible debris from the fuel fill opening. Insert either the fuel
fill nozzle or the fuel fill funnel (see Refilling with a portable fuel
container for funnel location) provided with the vehicle several times to
dislodge any debris and/or allow the inlet to close properly. If this action
corrects the problem, the Check Fuel Fill Inlet message may not reset
immediately. It may take several driving cycles for the Check Fuel Fill
Inlet message to turn off. A driving cycle consists of an engine start-up
(after four or more hours with the engine off) followed by city/highway
driving. Continuing to drive with the Check Fuel Fill Inlet message on
may cause the service engine soon lamp to turn on as well.
WARNING: The fuel system may be under pressure. If you hear
a hissing sound near the fuel filler door (Easy Fuel™ "no cap"
fuel system), do not refuel until the sound stops. Otherwise, fuel may
spray out, which could cause serious personal injury.
Choosing the right fuel
Use only UNLEADED fuel or UNLEADED fuel blended with a maximum
of 10% ethanol. Do not use fuel ethanol (E85), diesel, methanol, leaded
fuel or any other 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.
Note: Use of any fuel other than those recommended may cause
powertrain damage, a loss of vehicle performance, and repairs may not
be covered under warranty.
Octane recommendations
3.7L V6 engine
Your vehicle will run normally on 87 octane regular fuel. Premium fuel
will provide improved performance.
Maintenance and Specifications
325