2004 Mercury Grand Marquis schedule

•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

•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.
•Driving at reasonable speeds (traveling at 88 km/h [55 mph] uses 15%
less fuel than traveling at 105 km/h [65 mph]).
•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 third and fourth gear 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 toLubricant specificationsin
this chapter.
•Perform all regularly scheduled maintenance items. Follow the
recommended maintenance schedule and owner maintenance checks
found in your vehicle scheduled maintenance guide.
Conditions
•Heavily loading a vehicle or towing a trailer may reduce fuel economy
at any speed.
•Carrying unnecessary weight may reduce fuel economy (approximately
0.4 km/L [1 mpg] is lost for every 180 kg [400 lb] 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.
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
203

•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

present, theCheck engine/Service engine soonlight should turn off. (A
driving cycle consists of a cold engine startup followed by mixed
city/highway driving.) No additional vehicle service is required.
If theCheck engine/Service engine soonlight remains on, have your
vehicle serviced at the first available opportunity.
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 diagnostics system. If yourCheck engine/Service engine
soonlight is on, refer to the description in theWarning lights and
chimessection of theInstrument Clusterchapter. Your vehicle may not
pass the I/M test with theCheck engine/Service engine soonlight on.
If the vehicle’s powertrain system or its battery has just been serviced,
the on-board diagnostics system is reset to a“not ready for I/M test”
condition. To ready the on-board diagnostics system for I/M testing, a
minimum of 30 minutes of city and highway driving is necessary as
described below:
•First, at least 10 minutes of driving on an expressway or highway.
•Next, 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.
CHECKING AND ADDING POWER STEERING FLUID
Check the power steering fluid.
Refer to the scheduled maintenance
guide for the service interval
schedules.If adding fluid is
necessary, use only MERCON
AT F.
1. Start the engine and let it run until it reaches normal operating
temperature (the engine coolant temperature gauge indicator will be
near the center of the normal area between H and C).
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
206

2. While the engine idles, turn the steering wheel left and right several
times.
3. Turn the engine off.
4. Check the fluid level in the
reservoir. It should be between the
MIN and MAX lines. Do not add
fluid if the level is in this range.
5. If the fluid is low, add fluid in small amounts, continuously checking
the level until it reaches the range between the MIN and MAX lines. Be
sure to put the cap back on the reservoir.
BRAKE FLUID RESERVOIR
The fluid level will drop slowly as
the brakes wear, and will rise when
the brake components are replaced.
Fluid levels below the“MAX”line
that do not trigger the brake system
warning lamp are within the normal
operating range, there is no need to
add fluid. If the fluid levels are outside of the normal operating range,
the performance of your brake system could be compromised, seek
service from your dealer immediately.
TRANSMISSION FLUID
Checking automatic transmission fluid (if equipped)
Refer to yourScheduled Maintenance Guidefor scheduled intervals for
fluid checks and changes. Your transmission does not consume fluid.
However, the fluid level should be checked if the transmission is not
working properly, i.e., if the transmission slips or shifts slowly or if you
notice some sign of fluid leakage.
Automatic transmission fluid expands when warmed. To obtain an
accurate fluid check, drive the vehicle until it is at normal operating
temperature (approximately 30 km [20 miles]). If your vehicle has been
operated for an extended period at high speeds, in city traffic during hot
DONOTOVERFILLPOWERSTEERINGFLUID
MAX
MIN
MAX
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
207

If an overfill occurs, excess fluid
should be removed by a qualified
technician.
An overfill condition of
transmission fluid may cause
shift and/or engagement
concerns and/or possible
damage.
Do not use supplemental transmission fluid additives, treatments or
cleaning agents. The use of these materials may affect transmission
operation and result in damage to internal transmission components.
AIR FILTER MAINTENANCE
Refer to the scheduled maintenance guide for the appropriate intervals
for changing the air filter element.
When changing the air filter element, use only the Motorcraft air filter
element listed. Refer toMotorcraft part numbersin this chapter.
Note:Do not start your engine with the air cleaner removed and do not
remove it while the engine is running.
Changing the air filter element
1. Release the clamps that secure the air filter housing cover.
2. Carefully separate the two halves of the air filter housing.
3. Remove the air filter element from the air filter housing.
4. Wipe the air filter housing and cover clean to remove any dirt or
debris and to ensure good sealing.
5. Install a new air filter element. Be
careful not to crimp the filter
element edges between the air filter
housing and cover. This could cause
filter damage and allow unfiltered
air to enter the engine if not
properly seated.
6. Replace the air filter housing cover and secure the clamps.
7. Replace the air inlet tube and secure the clamp.
DON’T ADD
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
210

Note:Some spare tires require higher inflation pressure than the other
tires. Check the tire label on the B pillar or the driver’s door for the
recommended spare tire pressure.
6. Visually inspect the tires to make sure there are no nails or other
objects embedded that could poke a hole in the tire and cause an air
leak.
7. Check the sidewalls to make sure there are no gouges, cuts or bulges.
Tire and wheel alignment
A bad jolt from hitting a curb or pothole can cause the front end of your
vehicle to become misaligned or damage to your tires. If your vehicle
seems to pull to one side when you’re driving, the wheels may be out of
alignment. Have a qualified technician at a Ford or Lincoln/Mercury
dealer check the wheel alignment periodically.
Wheel misalignment in the front or the rear can cause uneven and rapid
treadwear of your tires and should be corrected by a qualified technician
at a Ford or Lincoln/Mercury dealer. Front wheel drive (FWD) vehicles,
and those with an independent rear suspension require alignment of all
four wheels.
The tires should also be balanced periodically. An unbalanced tire and
wheel assembly may result in irregular tire wear.
Tire rotation
Rotating your tires at the recommended interval (as indicated in the
Scheduled Maintenance Guidethat comes with your vehicle) will help
your tires wear more evenly providing better tire performance and longer
tire life. Unless otherwise specified, rotate the tires approximately every
5,000 miles (8,000 km).
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
219

•The suspension insulation and bumpers will help prevent vehicle
damage. Do not remove these components from your vehicle when
using snow tires and chains.
MOTORCRAFT PART NUMBERS
Component 4.6L SOHC V8 engine
Air filter element FA-1668
Fuel filter FG-986B
Battery-standard BXT-65–650
Battery-heavy duty BXT-65–750
Oil filter FL-820-S
PCV valve
1
Spark plugs2
1
The PCV valve is a critical emission component. It is one of the items
listed in theScheduled Maintenance Guideand is essential to the life
and performance of your vehicle and to its emissions system.
For PCV valve replacement, see your dealer or a qualified service
technician. Refer to theScheduled Maintenance Guidefor 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 dealer or a qualified service
technician. Refer to theScheduled Maintenance Guidefor 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.
Refer to Vehicle Emissions Control Information (VECI) decal for spark
plug gap information.
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
224