2004 JEEP WRANGLER spark plugs replace

MAINTAINING YOUR VEHICLE
CONTENTS
m2.4L Engine..........................223
m4.0L Engine..........................224
mOnboard Diagnostic System Ð OBD II......225
mEmissions Inspection And
Maintenance Programs
..................226
mReplacement Parts.....................227
mDealer Service........................227
mMaintenance Procedures.................228
NEngine Oil..........................228
NDrive Belts Ð Check Condition And Tension . . 231
NSpark Plugs.........................232
NCatalytic Converter....................232NEngine Timing Belt Ð 2.4L Engine.........233
NIgnition Wiring System Ð 2.4L Engine......233
NCrankcase Emission Control System........234
NFuel Filter..........................234
NEngine Air Cleaner Filter................234
NMaintenance-Free Battery................234
NAir Conditioner Maintenance.............235
NPower Steering Fluid Check..............236
NDriveline And Steering Component
Lubrication..........................237
NBody Lubrication.....................237
NWindshield Wiper Blades................237
7

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.
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.
232 MAINTAINING YOUR VEHICLE

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
Inspect the PCV Valve, and replace if necessary.LX
Replace the spark plugs.X
Lubricate the steering linkage tie rod ends. X X X X X
Lubricate the steering and suspension ball joints. X X X
Inspect the brake linings. X
Drain and refill the front and rear axle fluid³ X
Inspect the transfer case fluid, add if necessary. X
266 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
Inspect the PCV Valve, and replace if necessary.LX
Inspect the ignition cables, and replace if neces-
sary (2.4L Only).X
Replace the spark plugs.X
Lubricate the steering linkage tie rod ends. X X X X X
Lubricate the steering and suspension ball joints. X X 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 change filter.X
Inspect the drive belt and replace as needed. Not
required if belt was previously.X
Drain and refill the transfer case fluid. X
268 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
Inspect the PCV Valve, and replace if necessary.LX
Replace the spark plugs.X
Lubricate the steering linkage tie rod ends. X X X X X
Lubricate the steering and suspension ball joints. X X X
Replace the timing belt (2.4L Only).X
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
Inspect the transfer case fluid, add if necessary. X
270 SCHEDULE ªBº
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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
Inspect the PCV Valve, and replace if necessary.LX
Replace the spark plugs.X
Inspect the ignition cables, and replace if neces-
sary (2.4L Only).X
Lubricate the steering linkage tie rod ends. X X X X X
Lubricate the steering and suspension ball joints. X X 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
Inspection and service should also be performed anytime
a malfunction is observed or suspected. Retain all re-
ceipts.LThis maintenance is recommended by the manufac-
turer to the owner, but is not required to maintain
emissions warranty.
272 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
Lubricate the steering linkage joints and outer tie
rod ends.X X XXX
Lubricate the steering and suspension ball joints. X X
Inspect the brake linings. X
Inspect the transfer case fluid.X
274 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 engine air filter element, and replace if nec-
essary.X
Inspect the PCV Valve, and replace if necessary.LX
Replace the ignition cables (2.4L Only).X
Replace the spark plugs.X
Lubricate the steering linkage joints and outer tie rod
ends.XXXX
Lubricate the steering and suspension ball joints. X X
Inspect the brake linings. X
Inspect the drive belt, and replace as needed. X
Inspect the drive belt, and replace as needed. Not re-
quired if belt was previously replaced.X
Flush and replace the engine coolant at 60 months, re-
gardless of mileage.X
Inspect transfer case fluid. X
276 SCHEDULE ªAº
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