2008 Mercury Grand Marquis fuel cap

“Fuel Ethanol ”. To identify if your vehicle is an FFV, it may be
equipped with a yellow fuel cap with the writing “E85/Gasoline”, or
check if there is a label on the fuel filler door, or check your VIN.
When checking the VIN look for the engine type identifier (8th
character). If your vehicle is an FFV, then the character will be
labeled as a “2.”
Pure ethanol is the alcohol which is the intoxicating agent in liquor, beer
and wine. It is distilled from the fermentation of plants such as field corn
and sugar cane. When ethanol is produced for use in motor fuels, a small
amount of gasoline is added to make it unfit for beverage use. The
resulting ethanol blend is called denatured fuel ethanol meaning that it is
denatured with 2% to 5% gasoline and is suitable for automotive use.
During the summer season, fuel ethanol may contain a maximum of 85%
denatured ethanol (Ed85) and 15% unleaded gasoline. The fuel ethanol
has a higher octane rating than unleaded regular or premium gasoline
and this allows the design of engines with greater efficiency and power.
Winter blends may contain up to 75% denatured ethanol (Ed75) and up
to 25% unleaded gasoline to enhance cold engine starts. Severely cold
weather may require additional measures for reliable starting. Refer to
Cold Weather Startingin theDrivingchapter.
Ethanol is more chemically active than gasoline. It corrodes some metals
and causes some plastic and rubber components to swell, break down or
become brittle and crack, especially when mixed with gasoline. Special
materials and procedures have been developed for flexible fuel vehicles
and the dispensers used by ethanol fuel providers.
Flexible fuel components and standard unleaded gasoline fuel
components are not interchangeable. If your vehicle is not
serviced in accordance with flexible fuel vehicles procedures, damage
may occur and your warranty may be invalidated.
When refueling always shut the engine off and never allow
sparks or open flames near the filler neck. Never smoke while
refueling. Fuel vapor is extremely hazardous under certain conditions.
Care should be taken to avoid inhaling excess fumes.
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The flow of fuel through a fuel pump nozzle can produce static
electricity, which can cause a fire if fuel is pumped into an
ungrounded fuel container.
Refueling
Fuel vapor burns violently and a fuel fire can cause severe
injuries. To help avoid injuries to you and others:
•Read and follow all the instructions on the pump island;
•Turn off your engine when you are refueling;
•Do not smoke if you are near fuel or refueling your vehicle;
•Keep sparks, flames and smoking materials away from fuel;
•Stay outside your vehicle and do not leave the fuel pump unattended
when refueling your vehicle — this is against the law in some places;
•Keep children away from the fuel pump; never let children pump fuel
Use the following guidelines to avoid electrostatic charge build-up when
filling an ungrounded fuel container:
•Place approved fuel container on the ground.
•DO NOT fill a fuel container while it is in the vehicle (including the
cargo area).
•Keep the fuel pump nozzle in contact with the fuel container while
filling.
•DO NOT use a device that would hold the fuel pump handle in the fill
position.
Fuel Filler Cap
Your fuel tank filler cap has an indexed design with a 1/4 turn on/off
feature.
When fueling your vehicle:
1. Turn the engine off.
2. Carefully turn the filler cap counterclockwise 1/4 of a turn until it
stops.
3. Pull to remove the cap from the fuel filler pipe.
4. To install the cap, align the tabs on the cap with the notches on the
filler pipe.
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5. Turn the filler cap clockwise 1/4 of a turn until it clicks at least once.
If the check fuel cap lamp
or a “check fuel cap” message comes on,
the fuel filler cap may not be properly installed. The lamp or message
can come on after several driving events after you’ve refueled your
vehicle.
At the next opportunity, safely pull off of the road, remove the fuel filler
cap, align the cap properly and reinstall it. The check fuel cap
lamp
or “check fuel cap” message may not reset immediately; it may
take several driving cycles for the check fuel cap lamp
or “check fuel
cap” 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 and
highway driving.
Continuing to drive with the check fuel cap lamp
or “check fuel cap”
message on may cause the
lamp to turn on as well.
If you must replace the fuel filler cap, replace it with a fuel filler
cap that is designed for your vehicle. The customer warranty may
be void for any damage to the fuel tank or fuel system if the
correct genuine Ford or Motorcraft fuel filler cap is not used.
The fuel system may be under pressure. If the fuel filler cap is
venting vapor or if you hear a hissing sound, wait until it stops
before completely removing the fuel filler cap. Otherwise, fuel may
spray out and injure you or others.
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.
FFV (Flex Fuel Vehicle) Fuel Cap
If your vehicle is FFV capable it will have a yellow colored fuel cap.
Choosing the right fuel
If your vehicle is a flexible fuel vehicle (FFV), use only UNLEADED
FUEL and FUEL ETHANOL (Ed75–Ed85).
If your vehicle is not a flexible fuel vehicle (FFV), then only use
UNLEADED fuel or UNLEADED fuel blended with a maximum of 10%
ethanol. Your vehicle was not designed to run on E85 fuels that are
blended with a maximum of 85% ethanol. Do not use fuel containing
methanol. It can damage critical fuel system components.
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performance and emission control system protection for your vehicle.
Gasolines that meet the World-Wide Fuel Charter should be used when
available. Ask your fuel supplier about gasolines that meet the
World-Wide Fuel Charter.
Do not add aftermarket fuel additive products to your fuel tank. It
should not be necessary to add any aftermarket products to your fuel
tank if you continue to use high quality fuel of the recommended octane
rating. These products have not been approved for your engine and
could cause damage to the fuel system. Repairs to correct the effects of
using an aftermarket product in your fuel may not be covered by your
warranty.
Unleaded Gasoline engines
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 because it
may cause these problems to become more pronounced. If the problems
persist, see your authorized dealer.
FFV engine (if equipped)
To identify if your vehicle is an FFV, it may be equipped with a yellow
fuel cap with the writing “E85/Gasoline”, or check if there is a label on
the fuel filler door, or check your VIN. When checking the VIN, look for
the engine type identifier (8th character). If your vehicle is an FFV, then
the character will be labeled as a “2”.
If you operate your vehicle 50% or more of the time on ethanol, you
should follow a different maintenance schedule. In addition to this it is
also recommended to fill the fuel tank with regular unleaded gasoline
once every 3,000 miles (4,828 km). Seescheduled maintenance
informationfor more information.
Running out of fuel
Avoid running out of fuel because this situation may have an adverse
effect on powertrain components.
If you have run out of fuel:
•You may need to cycle the ignition from OFF to ON several times after
refueling to allow the fuel system to pump the fuel from the tank to
the engine. On restarting, cranking time will take a few seconds longer
than normal.
•Normally, adding 1 gallon (3.8L) of fuel is enough to restart the
engine. If the vehicle is out of fuel and on a steep grade, more than 1
gallon (3.8L) may be required.
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•Theindicator may come on. For more information on the “check
engine” or the “service engine soon” indicator, refer toWarning lights
and chimesin theInstrument Clusterchapter.
ESSENTIALS OF GOOD FUEL ECONOMY
Measuring techniques
Your best source of information about actual fuel economy is you, the
driver. You must gather information as accurately and consistently as
possible. Fuel expense, frequency of fill-ups or fuel gauge readings are
NOT accurate as a measure of fuel economy. We do not recommend
taking fuel economy measurements during the first 1,000 miles
(1,600 km) of driving (engine break-in period). You will get a more
accurate measurement after 2,000 miles–3,000 miles
(3,000 km–5,000 km).
Filling the tank
The advertised fuel capacity of the fuel tank on your vehicle is equal to
the rated refill capacity of the fuel tank as listed in theMaintenance
product specifications and capacitiessection of this chapter.
The advertised capacity is the amount of the indicated capacity and the
empty reserve combined. Indicated capacity is the difference in the
amount of fuel in a full tank and a tank when the fuel gauge indicates
empty. Empty reserve is the small amount of fuel remaining in the fuel
tank after the fuel gauge indicates empty.
The amount of usable fuel in the empty reserve varies and should
not be relied upon to increase driving range. When refueling your
vehicle after the fuel gauge indicates empty, you might not be
able to refuel the full amount of the advertised capacity of the
fuel tank due to the empty reserve still present in the tank.
For consistent results when filling the fuel tank:
•Turn the engine/ignition switch to the off position prior to refueling,
an error in the reading will result if the engine is left running.
•Use the same filling rate setting (low — medium — high) each time
the tank is filled.
•Allow no more than two automatic click-offs when filling.
•Always use fuel with the recommended octane rating.
•Use a known quality gasoline, preferably a national brand.
•Use the same side of the same pump and have the vehicle facing the
same direction each time you fill up.
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•Driving at reasonable speeds (traveling at 55 mph [88 km/h] uses 15%
less fuel than traveling at 65 mph [105 km/h]).
•Revving the engine before turning it off may reduce fuel economy.
•Using the air conditioner or defroster may reduce fuel economy.
•You may want to turn off the speed control in hilly terrain if
unnecessary shifting between the top gears occurs. Unnecessary
shifting of this type could result in reduced fuel economy.
•Warming up a vehicle on cold mornings is not required and may
reduce fuel economy.
•Resting your foot on the brake pedal while driving may reduce fuel
economy.
•Combine errands and minimize stop-and-go driving.
Maintenance
•Keep tires properly inflated and use only recommended size.
•Operating a vehicle with the wheels out of alignment will reduce fuel
economy.
•Use recommended engine oil. Refer toMaintenance product
specifications and capacitiesin this chapter.
•Perform all regularly scheduled maintenance items. Follow the
recommended maintenance schedule and owner maintenance checks
found inscheduled maintenance information.
Conditions
•Heavily loading a vehicle or towing a trailer may reduce fuel economy
at any speed.
•Carrying unnecessary weight may reduce fuel economy (approximately
1 mpg [0.4 km/L] is lost for every 400 lb [180 kg] of weight carried).
•Adding certain accessories to your vehicle (for example bug
deflectors, rollbars/light bars, running boards, ski/luggage racks) may
reduce fuel economy.
•Using fuel blended with alcohol may lower fuel economy.
•Fuel economy may decrease with lower temperatures during the first
8–10 miles (12–16 km) of driving.
•Driving on flat terrain offers improved fuel economy as compared to
driving on hilly terrain.
•Transmissions give their best fuel economy when operated in the top
cruise gear and with steady pressure on the gas pedal.
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An improperly operating or damaged exhaust system may allow exhaust
to enter the vehicle. Have a damaged or improperly operating exhaust
system inspected and repaired immediately.
Exhaust leaks may result in entry of harmful and potentially
lethal fumes into the passenger compartment.
Do not make any unauthorized changes to your vehicle or engine. By
law, vehicle owners and anyone who manufactures, repairs, services,
sells, leases, trades vehicles, or supervises a fleet of vehicles are not
permitted to intentionally remove an emission control device or prevent
it from working. Information about your vehicle’s emission system is on
the Vehicle Emission Control Information Decal located on or near the
engine. This decal identifies engine displacement and gives some tune up
specifications.
Please consult yourWarranty Guidefor complete emission warranty
information.
On board diagnostics (OBD-II)
Your vehicle is equipped with a computer that monitors the engine’s
emission control system. This system is commonly known as the On
Board Diagnostics System (OBD-II). The OBD-II system protects the
environment by ensuring that your vehicle continues to meet
government emission standards. The OBD-II system also assists your
authorized dealer in properly servicing your vehicle. When the
indicator illuminates, the OBD-II system has detected a malfunction.
Temporary malfunctions may cause the
indicator to illuminate.
Examples are:
1. The vehicle has run out of fuel—the engine may misfire or run poorly.
2. Poor fuel quality or water in the fuel—the engine may misfire or run
poorly.
3. The fuel cap may not have been securely tightened. SeeFuel filler
capin this chapter.
4. Driving through deep water—the electrical system may be wet.
These temporary malfunctions can be corrected by filling the fuel tank
with good quality fuel, properly tightening the fuel cap or letting the
electrical system dry out. After three driving cycles without these or any
other temporary malfunctions present, the
indicator should stay off
the next time the engine is started. A driving cycle consists of a cold
engine startup followed by mixed city/highway driving. No additional
vehicle service is required.
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Item Capacity Ford part nameFord part number /
Ford specification
Hinges, latches, striker
plates, fuel filler door
hinge and seat tracks— Multi-Purpose GreaseXG-4 or XL-5 /
ESB-M1C93-B
Lock cylinders —Motorcraft Penetrating
and Lock LubricantXL-1 /
None
Power steering fluidFill to line on
reservoirMotorcraft MERCONV
AT FXT-5-QM /
MERCONV
Automatic transmission
fluid (4R75E)13.9 quarts
(13.2L)
3
Motorcraft MERCONV
AT F
4
XT-5-QM /
MERCONV
Rear axle fluid
5
5.0 pints (2.4L)
6
Motorcraft SAE 80W-90
Premium Rear Axle
LubricantXY-80W90-QL /
WSP-M2C197-A
Windshield washer fluidFill to line on
reservoirMotorcraft Premium
Windshield Washer
ConcentrateZC-32-A /
WSB-M8B16-A2
Fuel Tank19.0 gallons
(71.9L)——
1Add the coolant type originally equipped in your vehicle.2Use of synthetic or synthetic blend motor oil is not mandatory. Engine oil need only meet the
requirements of Ford specification WSS-M2C930-A and the API Certification mark.3Indicates only approximate dry-fill capacity. Some applications may vary based on cooler size and
if equipped with an in-tank cooler. The amount of transmission fluid and fluid level should be set
by the indication on the dipstick’s normal operating range.
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