2004 JEEP LIBERTY check engine

The best time to check the engine oil level is about 5
minutes after a fully warmed engine has been shut off, or
before starting the engine after it has sat overnight.
Checking the oil while the vehicle is on level ground will
improve the accuracy of the oil level readings. Maintain
the oil level between the ADD and SAFE markings on the
dipstick. Adding 1 U.S. Quart (0.95L) of oil when the
reading is at the ADD mark will result in a SAFE reading
on these engines.
2.4L Engines
3.7L Engines
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CAUTION!
Overfilling or underfilling the crankcase will cause
aeration or loss of oil pressure. This could damage
your engine.
Change Engine Oil
Road conditions as well as your kind of driving affect the
interval at which your oil should be changed. Check the
following to determine if any apply to you:
²Day or night temperatures are below 32ÉF (0ÉC)
²Stop and go driving
²Extensive engine idling
²Driving in dusty conditions
²Short trip driving 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)
²Taxi, Police, or delivery service (commercial service)
²Trailer towing
²Off-road or desert driving
IfANYof these apply to you, then change your engine oil
at every interval shown in schedule ªBº of the ªMainte-
nance Schedulesº section of this manual.
If none of these apply to you, then change your engine oil
at every interval shown on schedule ªAº of the ªMain-
tenance Schedulesº section of this manual
NOTE:Under no circumstances should oil change in-
tervals exceed 6,000 miles (10 000 km) or 6 months
whichever comes first.
292 MAINTAINING YOUR VEHICLE

Materials Added To Engine Oils
The manufacturerstrongly recommendsagainst the ad-
dition of any additives (other than leak detection dyes) to
engine oil. Engine oil is an engineered product and it's
performance may be impaired by supplemental addi-
tives.
Disposing of Used Engine Oil
Care should be taken in disposing of used engine oil from
your vehicle. Used oil and oil filters, indiscriminately
discarded, can present a problem to the environment.
Contact your authorized dealer, service station, or gov-
ernmental agency for advice on how and where used oil
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
All of the manufacturer's engines have a full-flow type
disposable oil filter. Use a filter of this type for replace-
ment. The quality of replacement filters varies consider-
ably. Only high quality filters should be used to assure
most efficient service. Mopartengine oil filters are high
quality oil filters and are recommended.
Drive Belts Ð Check Condition and Tension
At the mileage shown in the appropriate ªMaintenance
Schedule,º check all drive belts for condition and proper
tension. Improper belt tension can cause belt slippage
and failure.
Inspect the drive belt for evidence of cuts, cracks, or
glazing and replace them if there is any sign of damage
which could result in belt failure. If adjustment is re-
quired, adjust the belts according to the specifications
and procedures shown in the Service Manual.
294 MAINTAINING YOUR VEHICLE

Special tools are required to properly measure tension
and to restore belt tension to factory specifications. Also,
check belt routing to make sure there is no interference
between the belts and other engine components.
Spark Plugs
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New plugs should be in-
stalled at the mileage specified in the appropriate main-
tenance chart. The entire set should be replaced if there is
any malfunction due to a faulty spark plug.
Refer to the ªVehicle Emission Control Informationº label
in the engine compartment for spark plug information.
Catalytic Converter
The catalytic converter requires the use of unleaded fuel
only. Leaded gasoline will destroy the effectiveness of the
converter as an emission control device.Under normal operating conditions, the catalytic con-
verter will not require maintenance. However, it is im-
portant to keep the engine properly tuned to assure
proper catalyst operation and prevent possible catalyst
damage.
CAUTION!
Damage to the catalytic converter can result if your
vehicle is not kept in proper operating condition. In
the event of engine malfunction, particularly involv-
ing engine misfire or other apparent loss of perfor-
mance, have your vehicle serviced promptly. Contin-
ued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and
vehicle.
MAINTAINING YOUR VEHICLE 295
7

Engine Timing Belt Ð 2.4L Engine
Replace the engine timing belt at the intervals described
in the appropriate maintenance schedule.
Ignition Wiring System Ð 2.4L Engine
Replace the ignition cables at the intervals described in
the appropriate maintenance schedule.
Crankcase Emission Control System
Proper operation of this system depends on freedom
from sticking or plugging due to deposits. As vehicle
mileage builds up, the PCV valve and passages may
accumulate deposits. If a valve is not working properly,
replace it with a new valve. DO NOT ATTEMPT TO
CLEAN THE OLD PCV VALVE!
Check ventilation hose for indication of damage or
plugging deposits. Replace if necessary.
Air Cleaner Filter
Under normal driving conditions, replace the air filter at
the intervals shown on ªMaintenance Schedule A.º If,
however, you drive the vehicle frequently under dusty or
severe conditions, the filter element should be inspected
periodically and replaced if necessary at the intervals
shown on ªMaintenance Schedule B.º
WARNING!
The air cleaner can provide protection in the case of
engine backfire. Do not remove the air cleaner
unless it is necessary for repair or maintenance.
Make sure that no one is near the engine compart-
ment before starting the vehicle with the air cleaner
removed. Failure to do so can result in serious
personal injury.
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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 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
ªDaimlerChrysler Dealership.º
WARNING!
Fluid level should be checked on a level surface with
the engine off to prevent injury from moving parts,
and to insure accurate fluid level reading. Do not
overfill. Use only the manufacturer's recommended
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.
300 MAINTAINING YOUR VEHICLE

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 for the windshield washers and the
rear window washer is shared. It is located in the front of
the engine compartment on the passenger side andshould be checked for fluid level at regular intervals. Fill
the reservoir with windshield washer solvent (not radia-
tor antifreeze) and operate the system for a few seconds
to flush out the residual water.
WARNING!
Commercial windshield washer solvents are flam-
mable. They could ignite and burn you. Care must
be exercised when filling or working around the
washer solution.
Exhaust System
The best protection against carbon monoxide entry into
the vehicle body is a properly maintained engine exhaust
system.
If you notice a change in the sound of the exhaust system;
or if the exhaust fumes can be detected inside the vehicle;
302 MAINTAINING YOUR VEHICLE

or when the underside or rear of the vehicle is damaged;
have an authorized technician inspect the complete ex-
haust system and adjacent body areas for broken, dam-
aged, 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 lubri-
cation or oil change. Replace as required.
Cooling System
WARNING!
You or others can be badly burned by hot coolant or
steam from your radiator. If you see or hear steam
coming from under the hood, don't open the hood
until the radiator has had time to cool. Never try to
open a cooling system pressure cap when the radia-
tor or coolant bottle is hot.
Coolant Checks
Check coolant protection 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 the front of the radiator for any accumulation of
bugs, leaves, etc. Clean the radiator by gently spraying
water from a garden hose at the back of the core.
Check the engine cooling system hoses for condition and
tightness of connection. Inspect the entire system for
leaks. Any hoses that show cuts or severe abrasion must
be replaced.
Cooling System Ð Drain, Flush, And Refill
At the intervals shown in the appropriate ªMaintenance
Schedule,º the system should be drained, flushed, and
refilled.
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