2004 Mercury Grand Marquis service

When the engine is cold, check the
level of the engine coolant in the
reservoir.
•The engine coolant should be at the“FULL COLD”level or within the
“COLD FILL RANGE”as listed on the engine coolant reservoir
(depending upon application).
•Refer to theScheduled Maintenance Guidefor service interval
schedules.
•Be sure to read and understandPrecautions when servicing your
vehiclein this chapter.
If the engine coolant has not been checked at the recommended interval,
the engine coolant reservoir may become low or empty. If the reservoir is
low or empty, add engine coolant to the reservoir. Refer toAdding
engine coolantin this chapter.
Note:Automotive fluids are not interchangeable; do not use engine
coolant, antifreeze or windshield washer fluid outside of its specified
function and vehicle location.
Adding engine coolant
When adding coolant, make sure it is a 50/50 mixture of engine coolant
and distilled water. Add the mixture to the coolant reservoir,when the
engine is cool, until the appropriate fill level is obtained.
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
191

Do not add engine coolant when the engine is hot. Steam and
scalding liquids released from a hot cooling system can burn you
badly. Also, you can be burned if you spill coolant on hot engine parts.
Do not put engine coolant in the windshield washer fluid
container. If sprayed on the windshield, engine coolant could
make it difficult to see through the windshield.
•Add Motorcraft Premium Gold Engine Coolant
(yellow-colored), VC-7–A (U.S., except CA and OR), VC-7–B
(CA and OR only), meeting Ford Specification
WSS-M97B51–A1.
Note:Use of Motorcraft Cooling System Stop Leak Pellets, VC-6, may
darken the color of Motorcraft Premium Gold Engine Coolant from
yellow to golden tan.
•Do not add/mix an orange-colored, extended life coolant such
as Motorcraft Speciality Orange Engine Coolant, VC-2 (US) or
CXC-209 (Canada), meeting Ford specification WSS-M97B44–D
with the factory-filled coolant.Mixing Motorcraft Speciality Orange
Engine Coolant or any orange-colored extended life product with your
factory filled coolant can result in degraded corrosion protection.
•A large amount of water without engine coolant may be added, in case
of emergency, to reach a vehicle service location. In this instance, the
cooling system must be drained and refilled with a 50/50 mixture of
engine coolant and distilled water as soon as possible. Water alone
(without engine coolant) can cause engine damage from corrosion,
overheating or freezing.
•Do not use alcohol, methanol, brine or any engine coolants
mixed with alcohol or methanol antifreeze (coolant).Alcohol
and other liquids can cause engine damage from overheating or
freezing.
•Do not add extra inhibitors or additives to the coolant.These
can be harmful and compromise the corrosion protection of the engine
coolant.
For vehicles with overflow coolant systems with a non-pressurized cap
on the coolant recovery system, add coolant to the coolant recovery
reservoir when the engine is cool. Add the proper mixture of coolant and
water to the“FULL COLD”level. For all other vehicles, which have a
coolant degas system with a pressurized cap, or if it is necessary to
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
192

•The air conditioning system will be disabled.
Continued operation will increase the engine temperature:
•If your vehicle is equipped with digital gauges, the gauge bars will
flash and a tone will sound every five seconds for one minute.
•The engine will completely shut down, causing steering and braking
effort to increase.
Once the engine temperature cools, the engine can be re-started. Take
your vehicle to a service facility as soon as possible to minimize engine
damage.
When fail-safe mode is activated
You have limited engine power when in the fail-safe mode, so drive the
vehicle with caution. The vehicle will not be able to maintain high-speed
operation and the engine will run rough. Remember that the engine is
capable of completely shutting down automatically to prevent engine
damage, therefore:
1. Pull off the road as soon as safely possible and turn off the engine.
2. Arrange for the vehicle to be taken to a service facility.
3. If this is not possible, wait a short period for the engine to cool.
4. Check the coolant level and replenish if low.
Never remove the coolant reservoir cap while the engine is
running or hot.
5. Re-start the engine and take your vehicle to a service facility.
Driving the vehicle without repairing the engine problem
increases the chance of engine damage. Take your vehicle to a
service facility as soon as possible.
WHAT YOU SHOULD KNOW ABOUT AUTOMOTIVE FUELS
Important safety precautions
Do not overfill the fuel tank. The pressure in an overfilled tank
may cause leakage and lead to fuel spray and fire.
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.
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
196

Cap light on, can activate the Service Engine Soon warning. When the
fuel filler cap is properly re-installed, the light(s) will turn off after a
period of normal driving.It may take a long period of time for the
system to detect an improperly installed fuel filler cap.
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 pressure or
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.
Do not use fuel containing methanol. It can damage critical fuel system
components.
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, many fuels contain critical fuel
system components.
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.
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
199

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.
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. Aftermarket products 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.
Many of the world’s automakers approved the World-wide Fuel Charter
that recommends gasoline specifications to provide improved
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.
Cleaner air
Ford endorses the use of reformulated“cleaner-burning”gasolines to
improve air quality.
Running out of fuel
Avoid running out of fuel because this situation may have an adverse
affect 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.
87(R+M)/2 METHOD
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
200

•Your“Check Engine”indicator may come on. For more information on
the“Check Engine”indicator, refer to theInstrument Cluster
chapter.
Fuel Filter
For fuel filter replacement, see your dealer or a qualified service
technician. Refer to the scheduled maintenance guide for the appropriate
intervals for changing the fuel filter.
Replace the fuel filter with an authorized Motorcraft part. The
customer warranty may be void for any damage to the fuel system
if an authorized Motorcraft fuel filter is not used.
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 1,600 km (1,000 miles)
of driving (engine break-in period). You will get a more accurate
measurement after 3,000 km–5,000 km (2,000 miles-3,000 miles).
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 theRefill capacities
section 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.
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
201

•Using fuel blended with alcohol may lower fuel economy.
•Fuel economy may decrease with lower temperatures during the first
12–16 km (8–10 miles) 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.
•Close windows for high speed driving.
EPA window sticker
Every new vehicle should have the EPA window sticker. Contact your
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 L/100 km (MPG)
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 in yourScheduled Maintenance Guide
performed according to the specified schedule.
The scheduled maintenance items listed in theScheduled Maintenance
Guideare 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.
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
204

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“Check Engine”light, 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.
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). This OBD-II system protects the
environment by ensuring that your vehicle continues to meet
government emission standards. The OBD-II system also assists the
service technician in properly servicing your vehicle. When theCheck
engine/Service engine soonlight illuminates, the OBD-II system has
detected a malfunction. Temporary malfunctions may cause yourCheck
engine/Service engine soonlight 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.
3. The fuel cap may not have been securely tightened.
These temporary malfunctions can be corrected by filling the fuel tank
with good quality fuel and/or properly tightening the fuel cap. After three
driving cycles without these or any other temporary malfunctions
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
205