2008 JEEP LIBERTY service

²The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine performance,
and damage the emission control system.
²An out-of-tune engine, or certain fuel or ignition
malfunctions, can cause the catalytic converter to
overheat. If you notice a pungent burning odor or
some light smoke, your engine may be out of tune or
malfunctioning and may require immediate service.
Contact your dealer for service assistance.
²The use of fuel additives, which are now being sold as
octane enhancers, is not recommended. Most of these
products contain high concentrations of methanol.
Fuel system damage or vehicle performance problems
resulting from the use of such fuels or additives is not
the responsibility of the manufacturer.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
Carbon Monoxide Warnings
WARNING!
Carbon monoxide (CO) in exhaust gases is deadly.
Follow the precautions below to prevent carbon
monoxide poisoning:
²Do not inhale exhaust gases. They contain carbon
monoxide, a colorless and odorless gas, which can kill.
Never run the engine in a closed area, such as a
garage, and never sit in a parked vehicle with the
engine running for an extended period. If the vehicle is
stopped in an open area with the engine running for
more than a short period, adjust the ventilation system
to force fresh, outside air into the vehicle.
358 STARTING AND OPERATING

IF YOUR ENGINE OVERHEATS
In any of the following situations, you can reduce the
potential for overheating by taking the appropriate ac-
tion.
²On the highways Ð Slow down.
²In city traffic Ð While stopped, put transmission in N
(Neutral), but do not increase engine idle speed.
NOTE:There are steps that you can take to slow down
an impending overheat condition. If your air conditioner
is on, turn it off. The air conditioning system adds heat to
the engine cooling system and turning off the A/C
removes this heat. You can also turn the Temperature
Control to maximum heat, the Mode Control to floor, and
the Fan Control to High. This allows the heater core to act
as a supplement to the radiator and aids in removing heat
from the engine cooling system.
CAUTION!
Driving with a hot cooling system could damage
your vehicle. If the temperature gauge reads ªH,º
pull over and stop the vehicle. Idle the vehicle with
the air conditioner turned off until the pointer drops
back into the normal range. If the pointer remains on
the ªH,º and you hear continuous chimes, turn the
engine off immediately, and call for service.
384 WHAT TO DO IN EMERGENCIES

JACKING AND TIRE CHANGING
WARNING!
²Getting under a jacked-up vehicle is dangerous.
The vehicle could slip off the jack and fall on you.
You could be crushed. Never get any part of your
body under a vehicle that is on a jack. If you need
to get under a raised vehicle, take it to a service
center where it can be raised on a lift.
²The jack is designed to use as a tool for changing
tires only. The jack should not be used to lift the
vehicle for service purposes. The vehicle should
be jacked on a firm level surface only. Avoid ice or
slippery areas.
Jack Location
The scissor-type jack and tire changing tools are located
in the cargo compartment behind a trim cover on the left
rear trim panel. The latch is located at the bottom of the
trim cover.
Jack Storage Location
WHAT TO DO IN EMERGENCIES 385
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nuts until each nut has been tightened twice. Correct
wheel nut tightness is 130 N´m (95 ft. lbs). If in doubt
about the correct tightness, have them checked with a
torque wrench by your authorized dealer or at a service
station.
10. Lower the jack to it's fully closed position.
WARNING!
A loose tire or jack, thrown forward in a collision or
hard stop could endanger the occupants of the ve-
hicle. Always stow the jack parts and the spare tire in
the places provided.
11. Secure the tire, jack, and tools in their proper loca-
tions.
JUMP STARTING
WARNING!
²Take care to avoid the radiator cooling fan whenever the hood is
raised. It can start anytime the ignition switch is on. You can be hurt
by the fan.
²Do not attempt to push or tow your vehicle to get it started. Vehicles
equipped with an automatic transmission cannot be started this
way. Unburned fuel could enter the catalytic converter and once the
engine has started, ignite and damage the converter and vehicle. If
the vehicle has a discharged battery, booster cables may be used to
obtain a start from another vehicle. This type of start can be
dangerous if done improperly, so follow this procedure carefully.
²Battery fluid is a corrosive acid solution; do not allow battery fluid
to contact eyes, skin, or clothing. Don't lean over battery when
attaching clamps or allow the clamps to touch each other. If acid
splashes in eyes or on skin, flush contaminated area immediately
with large quantities of water.
²A battery generates hydrogen gas, which is flammable and explo-
sive. Keep flame or spark away from the vent holes.
²Do not use a booster battery or any other booster source with an
output that exceeds 12 volts.
390 WHAT TO DO IN EMERGENCIES

MAINTAINING YOUR VEHICLE
CONTENTS
m3.7L Engine Compartment................398
mOnboard Diagnostic System Ð OBD II........399
NLoose Fuel Filler Cap Message............400
mEmissions Inspection And Maintenance
Programs............................400
mReplacement Parts......................402
mDealer Service.........................402
mMaintenance Procedures..................402
NEngine Oil..........................403NEngine Oil Filter......................405
NDrive Belts Ð Check Condition And Tension . . 406
NSpark Plugs.........................406
NEngine Air Cleaner Filter................406
NFuel Filter..........................407
NCatalytic Converter....................407
NCrankcase Emission Control System........409
NMaintenance-Free Battery................409
NAir Conditioner Maintenance.............411
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ONBOARD DIAGNOSTIC SYSTEM Ð OBD II
Your vehicle is equipped with a sophisticated onboard
diagnostic system called OBD II. This system monitors
the performance of the emissions, engine, and automatic
transmission control systems. When these systems are
operating properly, your vehicle will provide excellent
performance and fuel economy, as well as engine emis-
sions well within current government regulations.
If any of these systems require service, the OBD II system
will turn on the ªMalfunction Indicator Light.º It will
also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be drivable and not
need towing, see your dealer for service as soon as
possible.CAUTION!
²Prolonged driving with the ªMalfunction Indica-
tor Lightº on could cause further damage to the
emission control system. It could also affect fuel
economy and driveability. The vehicle must be
serviced before any emissions tests can be per-
formed.
²If the ªMalfunction Indicator Lightº is flashing
while the engine is running, severe catalytic con-
verter damage and power loss will soon occur.
Immediate service is required.
MAINTAINING YOUR VEHICLE 399
7

Loose Fuel Filler Cap Message
If the vehicle diagnostic system determines that the fuel
filler cap in loose, improperly installed, or damaged, a
ªgASCAPº message will display in the instrument clus-
ter. Tighten the gas cap until a ªclickingº sound is heard.
This is an indication that the gas cap is properly tight-
ened. Press the trip odometer reset button to turn off the
message. If the problem persists, the message will appear
the next time the vehicle is started. This might indicate a
damaged cap. If the problem is detected twice in a row,
the system will turn on the Malfunction Indicator Light
(MIL). Resolving the problem will turn the MIL light off.
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of your vehicle's emissions control system.
Failure to pass could prevent vehicle registration.For states, which have an I/M (Inspection and
Maintenance) requirement, this check verifies the
following: the MIL (Malfunction Indicator Light)
is functioning and is not on when the engine is running,
and that the OBD (On Board Diagnostic) system is ready
for testing.
Normally, the OBD system will be ready. The OBD
system maynotbe ready if your vehicle was recently
serviced, if you recently had a dead battery, or a battery
replacement. If the OBD system should be determined
not ready for the I/M test, your vehicle may fail the test.
Your vehicle has a simple ignition key actuated test,
which you can use prior to going to the test station. To
check if your vehicle's OBD system is ready, you must do
the following:
1. Insert your ignition key into the ignition switch.
400 MAINTAINING YOUR VEHICLE

2. Turn the ignition to the ON position, but do not crank
or start the engine.
3. If you crank or start the engine, you will have to start
this test over.
4. As soon as you turn your key to the ON position, you
will see your MIL symbol come on as part of a normal
bulb check.
5. Approximately 15 seconds later, one of two things will
happen:
a. The MIL will flash for about 10 seconds and then
return to being fully illuminated until you turn off the
ignition key or start the engine. This means that your
vehicle's OBD system isnot readyand you shouldnot
proceed to the I/M station.b. The MIL will not flash at all and will remain fully
illuminated until you turn off the ignition key or start
the engine. 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
authorized 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 your
vehicle 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.
MAINTAINING YOUR VEHICLE 401
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