2008 JEEP LIBERTY check engine

These items should be inspected if a malfunction is
observed or suspected.
Engine Oil
Checking Oil Level
To assure proper engine lubrication, 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.
Checking the oil while the vehicle is on level ground will
improve the accuracy of the oil level readings. Always
maintain the oil level within the SAFE zone on the
dipstick. Adding one quart of oil when the reading is at
the bottom of the SAFE zone will result in a reading at the
top of the safe zone on these engines.
CAUTION!
Do not overfill the engine. Overfilling the engine
will cause oil aeration, which can lead to loss of oil
pressure and an increase in oil temperature. This
could damage your engine. Also, be sure the oil fill
cap is replaced and tightened after adding oil.
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Drive Belts Ð Check Condition and Tension
Belt tension is controlled by means of an automatic
tensioner. Therefore, no belt tension adjustments are
required. However, belt and belt tensioner condition
should be inspected periodically and replaced if re-
quired. Improper belt tension can cause belt slippage and
failure. Low generator belt tension can cause battery
failure.
Inspect belts for evidence of cuts, cracks, glazing, or
frayed cords and replaced if there is indication of dam-
age, which could result in belt failure. Also, check belt
routing to make sure there is no interference between the
belts and other engine components. See your authorized
dealer for service.
Spark Plugs
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New plugs should be in-
stalled at the specified mileage. The entire set should be
replaced if there is any malfunction due to a faulty spark
plug. Malfunctioning spark plugs can damage the cata-
lytic converter. Refer to ªFluids, Lubricants, and Genuine
Partsº in this section for the proper type of spark plug for
use in your vehicle.
Engine Air Cleaner Filter
Refer to the ªMaintenance Scheduleº in Section 8 of this
manual for engine air cleaner filter maintenance inter-
vals.
NOTE:Be sure to follow the ªdusty or off-road condi-
tionsº maintenance interval if applicable.
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To minimize the possibility of catalytic converter dam-
age:
²Do not shut off the engine or interrupt the ignition
when the transmission is in gear and the vehicle is in
motion.
²Do not try to start the engine by pushing or towing the
vehicle.
²Do not idle the engine with any ignition coil connec-
tors disconnected for prolonged periods.
²Do not idle the engine for prolonged periods during
very rough idle or malfunctioning operating condi-
tions.
²Do not allow vehicle to run out of fuel.
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.
Maintenance-Free Battery
Your vehicle is equipped with a maintenance-free battery.
You will never have to add water, nor is periodic main-
tenance required.
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7

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:Use only manufacturer approved A/C System
Sealers, Stop Leak Products, Seal Conditioners, Compres-
sor Oil, and Refrigerants.
A/C Air Filter Ð If Equipped
Refer to the ªMaintenance Scheduleº in Section 8 of this
manual for A/C Air Filter service intervals.
WARNING!
Do not remove the A/C Air Filter while the blower is
operating or personal injury may result.
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 are
apparent, and/or the system is not functioning as antici-
pated. Coordinate inspection efforts through a certified
DaimlerChrysler Dealership.
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 manufacturer's recommended
power steering fluid.
412 MAINTAINING YOUR VEHICLE

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. Make sure that they are not frozen to the
glass before turning them on to avoid damaging the
blade.
Keep the blade rubber out of contact with petroleum
products such as engine oil, gasoline, etc.
NOTE:Always refer to the wiper blade packaging for
specific installation instructions. Many wiper blade re-
placements fit multiple vehicles.Windshield & Rear Window Washers
The windshield and rear window washers share the same
fluid reservoir. The fluid reservoir is located in the front
of the engine compartment. Be sure to check the fluid
level in the reservoir at regular intervals. Fill the reservoir
with windshield washer solvent (not radiator antifreeze)
and operate the system for a few seconds to flush out the
residual water.
When refilling the washer fluid reservoir, take some
washer fluid and apply it to a cloth or towel and wipe
clean the wiper blades, this will help blade performance.
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.
414 MAINTAINING YOUR VEHICLE

Cooling System
WARNING!
²When working near the radiator cooling fan, dis-
connect the fan motor lead or turn the ignition
switch to the LOCK position. The fan is tempera-
ture controlled and can start at any time the
ignition switch is in the ON position.
²You 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
radiator is hot.
Coolant Checks
Check engine coolant (antifreeze) 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 A/C condenser (if
equipped) or radiator for any accumulation of bugs,
leaves, etc. If dirty, clean by gently spraying water from a
garden hose vertically down the face of the A/C con-
denser (if equipped) or the back of the radiator core.
Check the engine cooling system hoses for brittle rubber,
cracking, tears, cuts, and tightness of the connection at
the coolant recovery bottle and radiator. Inspect the
entire system for leaks.
With the engine at normal operating temperature (but
not running), check the cooling system pressure cap for
proper vacuum sealing by draining a small amount of
coolant from the radiator drain cock. If the cap is sealing
416 MAINTAINING YOUR VEHICLE

The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.
WARNING!
²The warning words ªDO NOT OPEN HOTº on
the cooling system pressure cap are a safety pre-
caution. Never add coolant when the engine is
overheated. Do not loosen or remove the cap to
cool an overheated engine. Heat causes pressure to
build up in the cooling system. To prevent scald-
ing or injury, do not remove the pressure cap while
the system is hot or under pressure.
²Do not use a pressure cap other than the one
specified for your vehicle. Personal injury or en-
gine damage may result.
Disposal of Used Coolant
Used ethylene glycol based engine coolant is a regulated
substance requiring proper disposal. Check with your
local authorities to determine the disposal rules for your
community. To prevent ingestion by animals or children,
do not store ethylene glycol based engine coolant in open
containers or allow it to remain in puddles on the
ground. If ingested by a child, contact a physician
immediately. Clean up any ground spills immediately.
Coolant Level
The coolant bottle provides a quick visual method for
determining that the coolant level is adequate. With the
engine idling, and warm to normal operating tempera-
ture, the level of the coolant in the bottle should be
between the ranges indicated on the bottle.
The radiator normally remains completely full, so there is
no need to remove the radiator cap unless checking for
coolant freeze point or replacing coolant. Advise your
MAINTAINING YOUR VEHICLE 419
7

service attendant of this. As long as the engine operating
temperature is satisfactory, the coolant bottle need only
be checked once a month.
When additional coolant is needed to maintain the
proper level, it should be added to the coolant bottle. Do
not overfill.
Points To Remember
NOTE:When the vehicle is stopped after a few miles
(kilometers) of operation, you may observe vapor coming
from the front of the engine compartment. This is nor-
mally a result of moisture from rain, snow, or high
humidity accumulating on the radiator and being vapor-
ized when the thermostat opens, allowing hot coolant to
enter the radiator.
If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.
²Do not overfill the coolant bottle.
²Check coolant freeze point in the radiator and in the
coolant recovery bottle. If coolant needs to be added,
contents of coolant recovery bottle must also be pro-
tected against freezing.
²If frequent coolant additions are required, or if the
level in the coolant recovery bottle does not drop when
the engine cools, the cooling system should be pres-
sure tested for leaks.
²Maintain coolant concentration at 50% HOAT engine
coolant (minimum) and distilled water for proper
corrosion protection of your engine, which contains
aluminum components.
²Make sure that the radiator and coolant recovery
bottle hoses are not kinked or obstructed.
420 MAINTAINING YOUR VEHICLE