1998 Mercury Grand Marquis Owner's Manuals

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 compounds containing
methycyclopentadienyl manganese tricarbonyl (MMT). Some gasolines
that are not reformulated for low emissions contain the octane-enhancing
additive MMT. Ask your service station operator whether or not the fuel
you plan to purchase contains MMT. If fuels containing MMT are used,
spark plug life and the performance of the emission control devices and
systems may be adversely affected.
Vehicles certified to meet California emission standards (indicated on the
underhood Vehicle Emissions Control Information label) are designed to
operate on California reformulated gasolines. If California reformulated
gasoline is not available when you refuel, your vehicle can be operated
on non-California fuels. However, even though your engine will perform
adequately on other gasolines, the performance of the emission control
devices and systems may be adversely affected.
If the incorrect type of fuel is used continually, the ªCheck Engine/
Service Engine Soonº light may illuminate and/or your vehicle may fail an
emissions test. If in the event it is determined that the cause of the
condition is the type of fuel used, repair of damage caused by 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
ªRegularº unleaded gasoline with an
(R+M)/2 octane rating of 87. We do
not recommend gasolines labeled as
ªRegularº 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.
87
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Fuel quality
If you are experiencing starting, rough idle or hesitation driveability
problems during a cold start, try a different brand of ªRegularº unleaded
gasoline. ªPremiumº 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.
The American Automobile Manufacturers Association (AAMA) issued a
fuel specification to provide information on high quality fuels that
optimize the performance of your vehicle. We recommend the use of
fuels that meet the AAMA specification if they are available.
It should not be necessary to add any aftermarket products to your fuel
tank if you continue to use a high-quality fuel.
Cleaner air
Ford approves the use of gasolines to improve air quality, including
reformulated gasolines that contain oxygenates up to 10% ethanol or
15% MTBE.
Do not use gasolines containing methanol, which can damage critical fuel
system components. Damage resulting from the use of methanol may not
be covered by your warranty.
Running out of fuel
Avoid running out fuel because this situation may have an adverse affect
on powertrain components.
If you have run out of fuel: You may need to crank the engine several
times before the system starts to pump fuel from the tank to the engine.
If you run out of fuel, your Check Engine light may come on. For more
information on the Check Engine light, refer to theInstrumentation
chapter.
Calculating fuel economy
To accurately calculate your vehicle's fuel economy:
1. Fill the tank completely and record the initial odometer reading.
2. Each time you fill the tank, record the amount of fuel added (in liters
or gallons).
3. After at least three to five fuel tank fill-ups, fill the fuel tank and
record the current mileage reading.
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4. Use one of the following equations to calculate fuel economy.
Liters used x 1004Total kilometers traveled
Total miles traveled4Total gallons used
Keep a record for at least one month. This will provide an accurate
estimate of the vehicle's fuel economy.
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:
²Use only unleaded fuel.
²Avoid running out of fuel.
²Do not turn off the ignition while your vehicle is moving, especially at
high speeds.
²Have the items listed in your ªService Guideº performed according to
the specified schedule.
The scheduled maintenance items listed in the ªService Guideº are
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.
Lumination of the charging system warning light, ªCheck Engineº light or
the temperature warning light, fluid leaks, strange odors, smoke or loss
of oil pressure, could indicate that the emission control system is not
working properly.
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If you smell exhaust fumes of any kind inside your vehicle, have
the dealer inspect and fix your vehicle immediately. Do not drive
if you smell exhaust fumes. These fumes are harmful and could kill
you.
Do not make any unauthorized changes to your vehicle or engine. By
law, vehicle owners and anyone who manufactures, repairs, items, 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 your ªWarranty Guideº for complete emission warranty
information.
Readiness for inspection/maintenance (I/M) testing
In some localities, it may be a legal requirement to pass an I/M test of
the on-board diagnostic (OBD-II) system. If your ªCheck Engine/Service
Engine Soonº light is on, refer to the description in theWarning Lights
and Chimessection of theInstrumentationchapter. Your vehicle may
not pass the I/M test with the ªCheck Engine/Service Engine Soonº light
on.
If the vehicle's powertrain system or its battery has just been serviced,
the OBD-II system is reset to a ªnot ready for I/M testº condition. To
ready the OBD-II system for I/M testing, a minimum of 30 minutes of city
and highway driving is necessary as described below:
²First, at least 10 minutes of driving on an expressway or highway.
²Next, at least 20 minutes driving in stop-and-go, city-type traffic with
at least four 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.
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EXTERIOR BULBS
Replacing exterior bulbs
Check the operation of the following lamps frequently:
²Headlamps
²Tail lamps
²Brakelamps
²High-mount brakelamp
²Turn signals
²Backup lamps
²License plate lamp
Do not remove lamp bulbs unless they will be replaced immediately. If a
bulb is removed for an extended period of time, contaminants may enter
the lamp housings and affect performance.
Replacing headlamp bulbs
Handle a halogen headlamp bulb carefully and keep out of
children's reach. Grasp the bulb only by its plastic base and do
not touch the glass. The oil from your hand could cause the bulb to
break the next time the headlamps are operated.
To remove the headlamp bulb:
1. Make sure headlamp switch is in OFF position, then open the hood.
2. Remove the sight shield by turning the three knobs to the unlock
position.
3. Disengage the safety snap on the connector by pulling upward slightly
on the clip.
4. Release clip and disconnect the
electrical connector from the bulb.
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5. Remove the bulb retaining ring by
rotating it counterclockwise (when
viewed from the rear) about 1/8
turn to free it from the bulb socket,
and slide the ring off the plastic
base. Keep the ring to retain the
new bulb.
6. Remove the old bulb from its socket by gently pulling it straight back
out of the socket. Do not turn the bulb while removing it.
To install the new bulb:
1. With the flat side of the bulb's
plastic base facing upward, insert
the glass end of the bulb into the
socket. Turn the bulb left or right to
align the grooves in the plastic base
with the tabs in the socket. When
the grooves are aligned, push the
bulb into the socket until the plastic base contacts the rear of the socket.
2. Install the bulb retaining ring over the plastic base until it contacts the
rear of the socket by rotating it clockwise until you feel a ªstop.º
3. Connect the electrical connector into the rear of the plastic base until
it snaps, locking it into position.
4. Turn the headlamps on and make sure they work properly. If the
headlamp was correctly aligned before you changed the bulb, you should
not need to align it again.
Replacing parking lamp/turn signal bulbs
1. Make sure the headlamp control is in the OFF position.
2. Open the hood.
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3. Disconnect the electrical
connector from the bulb socket.
4. Rotate the bulb socket
counterclockwise about ò turn and
remove.
5. Without turning, carefully pull out
the bulb.
6. Insert the new bulb into the parking lamp assembly. When the grooves
in the plastic base are aligned, push the bulb into the lamp assembly
until the plastic base contacts the rear of the lamp assembly.
7. To complete installation of the parking lamp/turn signal assembly,
follow the removal procedures in reverse order.
Replacing tail lamp/backup bulbs
For bulb replacement, see a dealer or qualified technician.
Replacing sidemarker and cornering lamp bulbs
For bulb replacement, see a dealer or qualified technician.
High-mount brakelamp
For bulb replacement, see a dealer or qualified technician.
Replacing license plate lamp bulbs
For bulb replacement, see a dealer or qualified technician.
AIMING THE HEADLAMPS
The alignment of your headlamps should be checked by a qualified
service technician if:
1. Oncoming motorists frequently signal you to deactivate your high
beams, and your high beams are not activated.
2. The headlamps do not seem to provide enough light for clear night
vision.
3. The headlamp beams are pointed substantially away from a slightly
down and to the right position.
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REPLACING THE INTERIOR BULBS
Check the operation of the following interior bulbs frequently:
²interior overhead lamp
²map lamp
Using the right bulbs
Function Trade Number
Headlamp 9007
Park lamp and turn lamp (front) 3457 KNA
Side marker (front) 194 NA
Cornering lamp (front) 3156 K
Tail, stop, turn (rear) 3157 K
Side marker (rear) 194
Backup lamp 3156 K
License plate lamp 168
High-mount brakelamp 912
Luggage compartment lamp 212-2
Dome lamp 906
Rear reading lamp 211-2
Map lamp 168
Illuminated visor mirror 168
Dual floorwell lamp 906
Glove compartment 168
To replace all instrument panel lights - see your dealer.
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