2004 JEEP LIBERTY spark plugs replace

MAINTAINING YOUR VEHICLE
CONTENTS
m2.4L Engine...........................285
m3.7L Engine...........................286
mOnboard Diagnostic System Ð OBD II........287
mEmissions Inspection And Maintenance
Programs............................288
mReplacement Parts......................289
mDealer Service.........................289
mMaintenance Procedures..................290
NEngine Oil..........................290NDrive Belts Ð Check Condition And Tension . . 294
NSpark Plugs.........................295
NCatalytic Converter....................295
NEngine Timing Belt Ð 2.4L Engine.........297
NIgnition Wiring System Ð 2.4L Engine......297
NCrankcase Emission Control System........297
NAir Cleaner Filter.....................297
NMaintenance-Free Battery................298
NAir Conditioner Maintenance.............299
7

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

Miles 18,000 21,000 24,000 27,000 30,000
(Kilometers) (29 000) (34 000) (38 000) (43 000) (48 000)
Change the engine oil and engine oil filter. X X X X X
Inspect the engine air filter element, replace if
necessary.X
Replace the spark plugs.X
Inspect and replace the PCV valve, if necessary.LX
Inspect the brake linings. X
Drain and refill the front and rear axle fluid³ X
Inspect the transfer case fluid, add if necessary. X
334 SCHEDULE ªBº
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Miles 48,000 51,000 54,000 57,000 60,000
(Kilometers) (77 000) (82 000) (86 000) (91 000) (96 000)
Change the engine oil and engine oil filter. X X X X X
Inspect the engine air filter element, replace if
necessary.X
Replace the spark plugs.X
Inspect and replace the PCV valve, if necessary.LX
Replace the ignition cables (2.4L Only).X
Inspect the brake linings. X X
Drain and refill the front and rear axle fluid³ X X
Drain and refill the automatic transmission fluid,
and replace main sump filter.X
Inspect the drive belt and replace as needed. Not
required if belt was previouslyX
Drain and refill the transfer case fluid. X
336 SCHEDULE ªBº
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Miles 78,000 81,000 84,000 87,000 90,000
(Kilometers) (125 000) (130 000) (134 000) (139 000) (144 000)
Change the engine oil and engine oil filter. X X X X X
Inspect the engine air filter element, replace if
necessary.X
Replace the spark plugs.X
Inspect and replace the PCV valve, if necessary.LX
Inspect the brake linings. X
Drain and refill the front and rear axle fluid³ X
Inspect the drive belt and replace as needed. Not
required if belt was previously replaced.X
Replace the timing belt (2.4L Only).X
Inspect the transfer case fluid, add if necessary. X
338 SCHEDULE ªBº
8
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Miles 108,000 111,000 114,000 117,000 120,000
(Kilometers) (173 000) (178 000) (182 000) (187 000) (192 000)
Change the engine oil and engine oil filter. X X X X X
Inspect the engine air filter element, replace if
necessary.X
Replace the spark plugs.X
Inspect and replace the PCV valve, if necessary.LX
Replace the ignition cables (2.4L Only).X
Inspect the brake linings. X X
Drain and refill the front and rear axle fluid³ X X
Drain and refill the automatic transmission fluid,
and replace main sump filter.X
Inspect the drive belt and replace as needed. Not
required if belt was previously replaced.X
Drain and refill the transfer case fluid. X
340 SCHEDULE ªBº
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Schedule ªAº
Miles 6,000 12,000 18,000 24,000 30,000
(Kilometers) (10 000) (19 000) (29 000) (38 000) (48 000)
[Months] [6] [12] [18] [24] [30]
Change the engine oil and engine oil filter. X X X X X
Inspect the engine air filter element, and replace
if necessary.X
Replace the spark plugs.X
Inspect the brake linings. X
Inspect the transfer case fluid.X
342 SCHEDULE ªAº
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Miles 60,000 66,000 72,000 78,000
(Kilometers) (96 000) (106 000) (115 000) (125 000)
[Months] [60] [66] [72] [78]
Change the engine oil and engine oil filter. X X X X
Inspect the brake linings. X
Inspect the engine air filter element, and replace if nec-
essary.X
Replace the spark plugs.X
Inspect the ignition cables, and replace if necessary
(2.4L Only).X
Inspect and replace the PCV valve, if necessary.LX
Inspect the drive belt and replace, if needed. X
Inspect the drive belt and replace as needed. Not re-
quired if previously replaced.X
Flush and replace the engine coolant at 60 months, re-
gardless of mileage.X
Inspect the transfer case fluid. X
344 SCHEDULE ªAº
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