2004 DODGE DURANGO check engine

the key is turned off. This means that your vehicle's
OBD system isnot readyand you shouldnotproceed
to the I/M station.
b. The MIL light will remain fully illuminated until the
first engine crank or the key is turned off. This means
that your vehicle's OBD system isreadyand you can
proceed to the I/M station.
If your OBD system isnot ready,you should see your
dealer or repair facility. If your vehicle was recently
serviced or had a battery failure or replacement, you may
need to do nothing more than drive your vehicle as you
normally would in order for your OBD system to update.
A recheck with the above test routine may then indicate
that the system is now ready.
Regardless of whether your vehicle's OBD system is
ready or not ready, if the MIL symbol is illuminated
during normal vehicle operation, you should have yourvehicle serviced before going to the I/M station. The I/M
station can fail your vehicle because the MIL symbol is on
with the engine running.
REPLACEMENT PARTS
Use of genuine Mopartparts for normal/scheduled
maintenance and repairs is highly recommended to in-
sure the designed performance. Damage or failures
caused by the use of non-Mopartparts for maintenance
and repairs will not be covered by the manufacturer's
warranty.
DEALER SERVICE
Your dealer has the qualified service personnel, special
tools and equipment to perform all service operations in
an expert manner. Service manuals are available which
include detailed service information for your vehicle.
Refer to these manuals before attempting any procedure
yourself.
MAINTAINING YOUR VEHICLE 291
7

NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
WARNING!
You can be badly injured working on or around a
motor vehicle. Do only that service work for which
you have the knowledge and the proper equipment.
If you have any doubt about your ability to perform
a service job, take your vehicle to a competent
mechanic.
MAINTENANCE PROCEDURES
The pages that follow contain therequiredmaintenance
services determined by the engineers who designed your
vehicle.
Besides the maintenance items for which there are fixed
maintenance intervals, there are other items that should
operate satisfactorily without periodic maintenance.
However, if a malfunction of these items does occur, it
could adversely affect the engine or vehicle performance.
These items should be inspected if a malfunction is
observed or suspected.
Engine Oil
Checking Engine Oil Level
To assure proper lubrication of your vehicle's engine, the
engine oil must be maintained at the correct level. The
best time to check the engine oil level is about 5 minutes
after a fully warmed up engine is shut off or before
starting the engine after it has sat overnight.
292 MAINTAINING YOUR VEHICLE

Frequency Of Oil Change
Road conditions and your style of driving affect the
interval at which your oil should be changed. Check the
following to determine ifANYapply to you:
²Day or night temperatures are below 32ÉF (0ÉC).
²Stop and Go driving.
²Extensive engine idling.
²Driving in dusty conditions.
²Short trips of less than 10 miles (16.2 km).
²More than 50% of your driving is at sustained high
speeds during hot weather, above 90ÉF (32ÉC).
²Trailer towing, Taxi, Police or delivery service (com-
mercial service).
²Off-Road or desert operation.
²If equipped for and operating with E-85 (ethanol)
fuel.
NOTE:IfANYof these apply to you then change your
engine oil every 3,000 miles (5 000 km) or 3 months,
whichever comes first and follow schedule ªBº of the
9Maintenance Schedules9section of this manual.
If none of these apply to you, then change your engine oil
at every interval shown on schedule9A9of the9Mainte-
nance Schedules9section of this manual.
4x4 Models, If Used Primarily For Off-Road Operation
Every 50 hours of use.
Dusty Conditions
Driving through dust-laden air increases the problems of
keeping abrasive materials out of the engine. Under these
conditions, special attention should be given to the
engine air cleaner and the crankcase inlet air cleaner. The
crankcase ventilation system should also be checked
294 MAINTAINING YOUR VEHICLE

governmental agency for advice on how and where used
oil and oil filters can be safely discarded in your area.
Engine Oil Filter
The engine oil filter should be replaced at every engine
oil change.
Engine Oil Filter Selection
The manufacturer's engines have a full-flow type oil
filter. Use a filter of this type for replacement. The quality
of replacement filters varies considerably. Only high
quality filters should be used to assure most efficient
service. MopartEngine Oil Filters are a high quality oil
filter and are recommended.
Drive Belts Ð Check Condition and Tension
At the mileage indicated in the maintenance schedule, all
belts should be checked for condition and proper tension.
Improper belt tension can cause belt slippage and failure.Belts should be inspected for evidence of cuts, cracks, or
glazing, and replaced if there is indication of damage
which could result in belt failure. If adjustment is re-
quired, see your authorized dealer for service. Low
generator belt tension can cause battery failure. A special
tool is required to properly measure tension and to
restore belt tension to factory specifications.
Also check belt routing to make sure there is no interfer-
ence between the belts and other engine components.
Spark Plugs
Spark plugs must fire properly to assure proper engine
performance and emission control. The plugs installed in
your vehicle should operate satisfactorily in normal
service for the mileage indicated in the Maintenance
Chart. New plugs should be installed at this mileage. The
entire set should be replaced if there is any malfunction
MAINTAINING YOUR VEHICLE 297
7

due to a faulty spark plug. Check the Vehicle Emissions
Control Information label for the proper type of spark
plug for your vehicle.
CAUTION!
When replacing plugs, do not overtighten. You could
damage them and cause them to leak.
Ignition Cables
Replace the ignition cables (5.7L engines only) at the
mileage interval shown in the maintenance charts.
Engine Air Cleaner Filter
Under normal driving conditions, replace the air filter at
the intervals shown on Schedule ªAº. If, however, youdrive the vehicle frequently under dusty or severe con-
ditions, the filter element should be inspected periodi-
cally and replaced if necessary at the intervals shown on
Schedule ªBº.
WARNING!
The air cleaner can provide a measure of protection
in the case of engine backfire. Do not remove the air
cleaner unless such removal is necessary for repair or
maintenance. Make sure that no one is near the
engine compartment before starting the vehicle with
the air cleaner removed. Failure to do so can result in
serious personal injury.
298 MAINTAINING YOUR VEHICLE

Refrigerant Recovery and Recycling
R-134a Air Conditioning Refrigerant is a hydrofluorocar-
bon (HFC) that is endorsed by the Environmental Pro-
tection Agency and is an ozone-saving product. How-
ever, the manufacturer recommends that air conditioning
service be performed by dealers or other service facilities
using recovery and recycling equipment.
NOTE:Air Conditioning systems found to be contami-
nated with A/C System Sealers, Stop Leak Products, Seal
Conditioners, Compressor Oil, or Refrigerants not ap-
proved by the manufacturer, voids the warranty for the
Air Conditioning system.
Power Steering Ð Fluid Check
Checking the power steering fluid level at a defined
service interval is not required. The fluid should only be
checked if a leak is suspected, abnormal noises areapparent, and/or the system is not functioning as antici-
pated. Coordinate inspection efforts through a certified
DaimlerChrysler Dealership.9
WARNING!
Fluid level should be checked on a level surface and
with the engine off to prevent injury from moving
parts and to insure accurate fluid level reading. Do
not overfill. Use only manufacturers recommended
power steering fluid.
If necessary, add fluid to restore to the proper indicated
level. With a clean cloth, wipe any spilled fluid from all
surfaces. Refer to Recommended Fluids, Lubricants, and
Genuine Parts for correct fluid type.
MAINTAINING YOUR VEHICLE 303
7

Windshield Wiper Blades
The rubber edges of the wiper blades and the windshield
should be cleaned periodically with a sponge or soft cloth
and a mild nonabrasive cleaner. This will remove accu-
mulations of salt or road film.
Operation of the wipers on dry glass for long periods
may cause deterioration of the wiper blades. Always use
washer fluid when using the wipers to remove salt or dirt
from a dry windshield.
Avoid using the wiper blades to remove frost or ice from
the windshield. Keep the blade rubber out of contact with
petroleum products such as engine oil, gasoline, etc.
Windshield Washers
The fluid reservoir should be checked for fluid level at
regular intervals. When freezing weather is anticipated,
flush out the water in the reservoir by operating thesystem. Fill the reservoir with windshield washer anti-
freeze (not radiator antifreeze), and operate the system
for a few seconds to flush out the residual water.
To prevent freeze-up of your windshield washer system
in cold weather, select a solution or mixture that meets or
exceeds the temperature range of your climate. This
rating information can be found on most washer fluid
containers.
WARNING!
Commercially available windshield washer solvents
are flammable. They could ignite and burn you. Care
must be exercised when filling or working around
the washer solution.
After the engine has warmed, operate the defroster for a
few minutes to reduce the possibility of smearing or
MAINTAINING YOUR VEHICLE 305
7

freezing the fluid on the cold windshield. MopartAll
Weather Windshield Washer Solution used with water as
directed on the container, aids cleaning action, reduces
freezing point to avoid line clogging, and is not harmful
to paint or trim.
Exhaust System
The best protection against carbon monoxide entry into
the vehicle body is a properly maintained engine exhaust
system.
Whenever a change is noticed in the sound of the exhaust
system, when exhaust fumes can be detected inside the
vehicle, or when the underside or rear of the vehicle is
damaged, have a competent mechanic inspect the com-
plete exhaust system and adjacent body areas for broken,
damaged, deteriorated, or mispositioned parts. Open
seams or loose connections could permit exhaust fumes
to seep into the passenger compartment. In addition,inspect the exhaust system each time the vehicle is raised
for lubrication or oil change. Replace as required.
WARNING!
Exhaust gases can injure or kill. They contain carbon
monoxide (CO) which is colorless and odorless.
Breathing it can make you unconscious and can
eventually poison you. To avoid breathing CO, fol-
low the preceding safety tips.
Cooling System
Inspection
Coolant protection checks should be made at every 12
months (before the onset of freezing weather, where
applicable). If coolant is dirty or rusty in appearance, the
system should be drained, flushed and refilled with fresh
coolant. Check face of radiator for any accumulation of
306 MAINTAINING YOUR VEHICLE