2004 Mercury Grand Marquis check engine

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.
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remove the coolant pressure relief cap on the radiator of a vehicle with
an overflow system, follow these steps to add engine coolant.
To reduce the risk of personal injury, make sure the engine is
cool before unscrewing the coolant pressure relief cap. The
cooling system is under pressure; steam and hot liquid can come out
forcefully when the cap is loosened slightly.
1. Before you begin, turn the engine off and let it cool.
2. When the engine is cool, wrap a thick cloth around the coolant
pressure relief cap on the coolant reservoir (a translucent plastic bottle).
Slowly turn cap counterclockwise (left) until pressure begins to release.
3. Step back while the pressure releases.
4. When you are sure that all the pressure has been released, use the
cloth to turn it counterclockwise and remove the cap.
5. Fill the coolant reservoir slowly with the proper coolant mixture (see
above), to within the“COLD FULL RANGE”or the“FULL COLD”level
on the reservoir. If you removed the radiator cap in an overflow system,
fill the radiator until the coolant is visible and radiator is almost full.
6. Replace the cap. Turn until tightly installed. (Cap must be tightly
installed to prevent coolant loss.)
After any coolant has been added, check the coolant concentration, refer
toChecking engine coolant. If the concentration is not 50/50
(protection to–34°F/–36°C), drain some coolant and adjust the
concentration. It may take several drains and additions to obtain a 50/50
coolant concentration.
Whenever coolant has been added, the coolant level in the coolant
reservoir should be checked the next few times you drive the vehicle. If
necessary, add enough 50/50 concentration of engine coolant and
distilled water to bring the liquid level to the proper level.
If you have to add more than 1.0 liter (1.0 quart) of engine coolant per
month, have your dealer check the engine cooling system. Your cooling
system may have a leak. Operating an engine with a low level of coolant
can result in engine overheating and possible engine damage.
Recycled engine coolant
Ford Motor Company does NOT recommend the use of recycled engine
coolant in vehicles originally equipped with Motorcraft Premium Gold
Engine Coolant since a Ford-approved recycling process is not yet
available.
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What you should know about fail-safe cooling
If the engine coolant supply is depleted, this feature allows the vehicle to
be driven temporarily before incremental component damage is incurred.
The“fail-safe”distance depends on ambient temperatures, vehicle load
and terrain.
How fail-safe cooling works
•Standard cluster
•Optional cluster
If the engine begins to overheat:
•The engine coolant temperature gauge will move to the H (hot) area
(if your vehicle is equipped with analog gauges).
•The engine coolant temperature gauge will illuminate all eight bars
and a tone will sound every five seconds for one minute (if your
vehicle is equipped with digital gauges).
•TheCheck Engineindicator light will illuminate.
If the engine reaches a preset over-temperature condition, the engine
will automatically switch to alternating cylinder operation. Each disabled
cylinder acts as an air pump and cools the engine.
When this occurs the vehicle will still operate. However:
•The engine power will be limited.
TEMPH
C
N
O
R
M
H
C
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•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.
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splashed on the skin, promptly wash skin thoroughly with soap and
water. Consult a physician immediately if you experience an adverse
reaction.
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.
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.
Use the following guidelines to avoid static 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 1/8 turn on/off
feature.
When fueling your vehicle:
1. Turn the engine off.
2. Carefully turn the filler cap counterclockwise 1/8 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.
5. Turn the filler cap clockwise 1/8 of a turn until it stops.
“Check Fuel Cap”illuminates when the ignition is turned to the ON
position to ensure your bulb is working. When this light turns on, check
the fuel filler cap. Continuing to operate the vehicle with the Check Fuel
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•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.
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•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.
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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
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