2005 Mercury Montego check engine light

WARNING LIGHTS AND CHIMES
Warning lights and gauges can alert you to a vehicle condition that may
become serious enough to cause extensive repairs. A warning light may
illuminate when a problem exists with one of your vehicle’s functions.
Many lights will illuminate when you start your vehicle to make sure the
bulbs work. If any light remains on after starting the vehicle, have the
respective system inspected immediately.
Check engine:TheCheck Engine
indicator light illuminates when the
ignition is first turned to the ON
position to check the bulb. Solid
illumination after the engine is started indicates the On Board
Diagnostics System (OBD-II) has detected a malfunction. Refer toOn
board diagnostics (OBD-II)in theMaintenance and Specifications
chapter. If the light is blinking, engine misfire is occurring which could
damage your catalytic converter. Drive in a moderate fashion (avoid
heavy acceleration and deceleration) and have your vehicle serviced
immediately.
Under engine misfire conditions, excessive exhaust temperatures
could damage the catalytic converter, the fuel system, interior
floor coverings or other vehicle components, possibly causing a fire.
2005 Montego(mgo)
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Check fuel cap:Illuminates when
the fuel cap may not be properly
installed. Continued driving with
this light on may cause the Check
engine warning light to come on,
refer toFuel filler capin the
Maintenance and Specificationchapter.
Brake system warning light:To
confirm the brake system warning
light is functional, it will
momentarily illuminate when the
ignition is turned to the ON position
when the engine is not running, or in a position between ON and START,
or by applying the parking brake when the ignition is turned to the ON
position. If the brake system warning light does not illuminate at this
time, seek service immediately from your dealership. Illumination after
releasing the parking brake indicates low brake fluid level or a brake
system malfunction and the brake system should be inspected
immediately by your servicing dealership.
Driving a vehicle with the brake system warning light on is
dangerous. A significant decrease in braking performance may
occur. It will take you longer to stop the vehicle. Have the vehicle
checked by your dealer immediately.
Anti-lock brake system:If the
ABS light stays illuminated or
continues to flash, a malfunction has
been detected, have the system
serviced immediately. Normal
braking is still functional unless the brake warning light also is
illuminated.
Air bag readiness:If this light fails
to illuminate when ignition is turned
to ON, continues to flash or remains
on, have the system serviced
immediately. A chime will also sound when a malfunction in the
supplemental restraint system has been detected.
P!
BRAKE
ABS
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gear and drive steadily through the terrain. Apply the accelerator slowly
and avoid spinning the wheels.
If your vehicle is equipped with a 6–speed transmission:When
driving at slow speeds in deep sand under high outside temperatures,
use L (Low) gear when possible. L (Low) gear operation will maximize
the engine and transmission cooling capability.Do not perform this
operation if your vehicle is equipped with an
electronically-controlled CVT.
Under severe operating conditions, the A/C may cycle on and off to
protect overheating of the engine.
Avoid excessive speed because vehicle momentum can work against you
and cause the vehicle to become stuck to the point that assistance may
be required from another vehicle. Remember, you may be able to back
out the way you came if you proceed with caution.
Mud and water
If you must drive through high water, drive slowly. Traction or brake
capability may be limited.
When driving through water, determine the depth; avoid water higher
than the bottom of the hubs (if possible) and proceed slowly. If the
ignition system gets wet, the vehicle may stall.
Once through water, always try the brakes. Wet brakes do not stop the
vehicle as effectively as dry brakes. Drying can be improved by moving
your vehicle slowly while applying light pressure on the brake pedal.
Be cautious of sudden changes in vehicle speed or direction when you
are driving in mud. Even AWD vehicles can lose traction in slick mud. As
when you are driving over sand, apply the accelerator slowly and avoid
spinning your wheels. If the vehicle does slide, steer in the direction of
the slide until you regain control of the vehicle.
If the transmission, AWD system components or axles are submerged in
water, their fluids should be checked and changed, if necessary.
Driving through deep water may damage the transmission.
If the front or rear axle is submerged in water, the axle lubricant and
PTU (Power Transfer Unit) lubricant should be checked and changed if
necessary.
After driving through mud, clean off residue stuck to rotating driveshafts
and tires. Excess mud stuck on tires and rotating driveshafts causes an
imbalance that could damage drive components.
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SERVICE RECOMMENDATIONS
To help you service your vehicle:
•We highlight do-it-yourself items in the engine compartment for easy
location.
•We providescheduled maintenance informationwhich makes
tracking routine service easy.
If your vehicle requires professional service, your dealership can provide
the necessary parts and service. Check yourWarranty Guide/Owner
Information Guideto find out which parts and services are covered.
Use only recommended fuels, lubricants, fluids and service parts
conforming to specifications. Motorcraft parts are designed and built to
provide the best performance in your vehicle.
PRECAUTIONS WHEN SERVICING YOUR VEHICLE
•Do not work on a hot engine.
•Make sure that nothing gets caught in moving parts.
•Do not work on a vehicle with the engine running in an enclosed
space, unless you are sure you have enough ventilation.
•Keep all open flames and other burning (cigarettes) material away
from the battery and all fuel related parts.
Working with the engine off
1. Set the parking brake and shift to P (Park).
2. Turn off the engine and remove the key.
3. Block the wheels.
Working with the engine on
1. Set the parking brake and ensure the gearshift is securely latched in P
(Park).
2. Block the wheels to prevent the vehicle from moving unexpectedly.
Note:Do not start your engine with the air cleaner removed and do not
remove it while the engine is running.
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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.
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, premium grade fuel generally
contains more metallic additives than regular fuel. We recommend using
regular grade fuel. In Canada, many fuels contain metallic additives, but
fuels free of such additives may be available; check with your local fuel
dealer.
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.
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
87(R+M)/2 METHOD
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•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 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.
•Close windows for high speed driving.
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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 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 “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.
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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. SeeFuel filler
capin this chapter.
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
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.
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