fuel Mercury Grand Marquis 2008 s Service Manual

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.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
249

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.
Repairs to correct the effects of using a fuel for which your vehicle was
not designed may not be covered by your warranty.
Cleaner air
Ford endorses the use of reformulated “cleaner-burning” gasolines to
improve air quality, per the recommendations in theChoosing the Right
Fuelsection.
Octane recommendations
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 authorized dealer to prevent any engine damage.
Unleaded Gasoline Engines
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.
FFV engine (if equipped)
Your vehicle is designed to use Fuel Ethanol (Ed75–Ed85),“Regular”
unleaded gasoline or any mixture of the two fuels.
U.S. government regulations require fuel ethanol dispensing
pumps to have a small, square, orange and black label with the
common abbreviation or the appropriate percentage for that
region. Use of other fuels such as Fuel Methanol may cause
powertrain damage, a loss of vehicle performance, and your
warranty may be invalidated.
Fuel quality
Many of the world’s automakers approved the World-Wide Fuel Charter
that recommends gasoline specifications to provide improved
87(R+M)/2 METHOD
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
250

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.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
251

•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.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
252

•Have the vehicle loading and distribution the same every time.
Your results will be most accurate if your filling method is consistent.
Calculating fuel economy
1. Fill the fuel tank completely and record the initial odometer reading
(in miles or kilometers).
2. Each time you fill the tank, record the amount of fuel added (in
gallons or liters).
3. After at least three to five tank fill-ups, fill the fuel tank and record
the current odometer reading.
4. Subtract your initial odometer reading from the current odometer
reading.
5. Follow one of the simple calculations in order to determine fuel
economy:
Calculation 1:Divide total miles traveled by total gallons used.
Calculation 2:Multiply liters used by 100, then divide by total
kilometers traveled.
Keep a record for at least one month and record the type of driving (city
or highway). This will provide an accurate estimate of the vehicle’s fuel
economy under current driving conditions. Additionally, keeping records
during summer and winter will show how temperature impacts fuel
economy. In general, lower temperatures give lower fuel economy.
Driving style — good driving and fuel economy habits
Give consideration to the lists that follow and you may be able to change
a number of variables and improve your fuel economy.
Habits
•Smooth, moderate operation can yield up to 10% savings in fuel.
•Steady speeds without stopping will usually give the best fuel
economy.
•Idling for long periods of time (greater than one minute) may waste
fuel.
•Anticipate stopping; slowing down may eliminate the need to stop.
•Sudden or hard accelerations may reduce fuel economy.
•Slow down gradually.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
253

•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.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
254

•Close windows for high speed driving.
EPA window sticker
Every new vehicle should have the EPA window sticker. Contact your
authorized dealer if the window sticker is not supplied with your vehicle.
The EPA window sticker should be your guide for the fuel economy
comparisons with other vehicles.
It is important to note the box in the lower left corner of the window
sticker. These numbers represent the Range of MPG (L/100 km)
expected on the vehicle under optimum conditions. Your fuel economy
may vary depending upon the method of operation and conditions.
EMISSION CONTROL SYSTEM
Your vehicle is equipped with various emission control components and a
catalytic converter which will enable your vehicle to comply with
applicable exhaust emission standards. To make sure that the catalytic
converter and other emission control components continue to work
properly:
•Use only the specified fuel listed.
•Avoid running out of fuel.
•Do not turn off the ignition while your vehicle is moving, especially at
high speeds.
•Have the items listed inscheduled maintenance information
performed according to the specified schedule.
The scheduled maintenance items listed inscheduled maintenance
informationare essential to the life and performance of your vehicle
and to its emissions system.
If other than Ford, Motorcraft or Ford-authorized parts are used for
maintenance replacements or for service of components affecting
emission control, such non-Ford parts should be equivalent to genuine
Ford Motor Company parts in performance and durability.
Do not park, idle, or drive your vehicle in dry grass or other dry
ground cover. The emission system heats up the engine
compartment and exhaust system, which can start a fire.
Illumination of the
indicator, charging system warning light or the
temperature warning light, fluid leaks, strange odors, smoke or loss of
engine power could indicate that the emission control system is not
working properly.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
255

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.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
256

If theindicator remains on, have your vehicle serviced at the first
available opportunity. Although some malfunctions detected by the
OBD-II may not have symptoms that are apparent, continued driving
with the
indicator on can result in increased emissions, lower fuel
economy, reduced engine and transmission smoothness, and lead to more
costly repairs.
Readiness for Inspection/Maintenance (I/M) testing
Some state/provincial and local governments may have
Inspection/Maintenance (I/M) programs to inspect the emission control
equipment on your vehicle. Failure to pass this inspection could prevent
you from getting a vehicle registration. Your vehicle may not pass the I/M
test if the
indicator is on or not working properly (bulb is burned
out), or if the OBD-II system has determined that some of the emission
control systems have not been properly checked. In this case, the vehicle
is considered not ready for I/M testing.
If the
indicator is on or the bulb does not work, the vehicle may
need to be serviced. Refer to the On board diagnostics (OBD-II)
description in this chapter.
If the vehicle’s engine or transmission has just been serviced, or the
battery has recently run down or been replaced, the OBD-II system may
indicate that the vehicle is not ready for I/M testing. To determine if the
vehicle is ready for I/M testing, turn the ignition key to the ON position
for 15 seconds without cranking the engine. If the
indicator blinks
eight times, it means that the vehicle is not ready for I/M testing; if
the
indicator stays on solid, it means that the vehicle is ready for
I/M testing.
The OBD-II system is designed to check the emission control system
during normal driving. A complete check may take several days. If the
vehicle is not ready for I/M testing, the following driving cycle consisting
of mixed city and highway driving may be performed:
15 minutes of steady driving on an expressway/highway followed by 20
minutes of stop-and-go driving with at least four 30-second idle periods.
Allow the vehicle to sit for at least eight hours without starting the
engine. Then, start the engine and complete the above driving cycle. The
engine must warm up to its normal operating temperature. Once started,
do not turn off the engine until the above driving cycle is complete. If
the vehicle is still not ready for I/M testing, the above driving cycle will
have to be repeated.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
257

Note:Be sure the hinge features of the air filter cover to the air filter
housing are fully engaged when reassembling the air filter assembly.
Note:Failure to use the correct air filter element may result in severe
engine damage. The customer warranty may be void for any damage to
the engine if the correct air filter element is not used.
MOTORCRAFT PART NUMBERS
Component 4.6L SOHC V8
engine4.6L FFV SOHC V8
engine
Air filter element FA-1032 FA-1032
Fuel filter FG-986B FG-986B
Battery-standard BXT-65–650 BXT-65–650
Battery-heavy duty BXT-65–750 BXT-65–750
Oil filter FL-820-S FL-820-S
PCV valve
11
Spark plugs22
1
The PCV valve is a critical emission component. It is one of the items
listed inscheduled maintenance informationand is essential to the
life and performance of your vehicle and to its emissions system.
For PCV valve replacement, see your authorized dealer. Refer to
scheduled maintenance informationfor the appropriate intervals for
changing the PCV valve.
Replace the PCV valve with one that meets Ford material and
design specifications for your vehicle, such as a Motorcraft or
equivalent replacement part. The customer warranty may be void
for any damage to the emissions system if such a PCV valve is not
used.
2For spark plug replacement, see your authorized dealer. Refer to
scheduled maintenance informationfor the appropriate intervals for
changing the spark plugs.
Replace the spark plugs with ones that meet Ford material and
design specifications for your vehicle, such as Motorcraft or
equivalent replacement parts. The customer warranty may be
void for any damage to the engine if such spark plugs are not
used.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
262