warning JEEP LIBERTY 2002 KJ / 1.G Workshop Manual

INSTRUMENT CLUSTER - BLACK 20 WAY
CAV CIRCUIT FUNCTION
16 L62 20BR/RD RIGHT TURN SIGNAL
17 G11 20WT/BK RED BRAKE WARNING INDICATOR DRIVER
18 G29 20BK/TN LOW WASHER FLUID SENSE
19 F87 20TN/BK FUSED IGNITION SWITCH OUTPUT (RUN-START)
20 - -
INTAKE AIR TEMPERATURE SENSOR (GAS) - GRAY 2 WAY
CAV CIRCUIT FUNCTION
1 K4 18BK/LB SENSOR GROUND
2 K21 18BK/RD INTAKE AIR TEMPERATURE SENSOR SIGNAL
INTRUSION SENSOR (BUILT-UP-EXPORT) - BLACK 6 WAY
CAV CIRCUIT FUNCTION
1 Z2 20BK/LG GROUND
2- -
3 X75 20DG SIREN SIGNAL CONTROL
4- -
5 D25 20YL/VT PCI BUS
6 M1 20PK FUSED B(+)
JUNCTION BLOCK BODY CONTROL MODULE-JB - 26 WAY
CAV CIRCUIT FUNCTION
1 X3 (PREMIUM) HORN RELAY CONTROL
2 P334 DOOR UNLOCK RELAY CONTROL
3 L308 PARK LAMP RELAY CONTROL
4 L96 (PREMIUM) REAR FOG LAMP RELAY CONTROL
5 P109 (EXCEPT BASE) DRIVER DOOR UNLOCK RELAY CONTROL
6 C80 REAR WINDOW DEFOGGER RELAY CONTROL
7- -
8 Z300 GROUND
9 F35 FUSED B(+)
10 L309 HIGH BEAM RELAY CONTROL
11 P31 TAILGATE UNLOCK DRIVER
12 P37 DOOR LOCK SWITCH GROUND
13 L94 LOW BEAM RELAY CONTROL
14 F89 FUSED IGNITION SWITCH OUTPUT (RUN-ACC)
15 M1 FUSED B(+)
16 F87 FUSED IGNITION SWITCH OUTPUT (RUN-START)
17 L26 (EXCEPT BASE) FRONT FOG LAMP RELAY CONTROL
18 P333 DOOR LOCK RELAY CONTROL
19 V16 FRONT WIPER HIGH/LOW RELAY CONTROL
20 V55 FRONT WIPER PARK SWITCH SENSE
KJ8W-80 CONNECTOR PIN-OUTS8Wa-80-65

REAR POWER WINDOW SWITCH (MIDLINE/HIGHLINE) - WHITE 10 WAY
CAV CIRCUIT FUNCTION
1 Q28 14DG/WT RIGHT REAR WINDOW DRIVER DOWN
2 Q14 14GY RIGHT REAR WINDOW DRIVER UP
3 Q24 14DG RIGHT REAR WINDOW DRIVER DOWN
4 Q18 14GY/BK RIGHT REAR WINDOW DRIVER UP
5 Q1 16YL POWER WINDOW SWITCH FEED
6 Q1 16YL POWER WINDOW SWITCH FEED
7 Q17 14DB/WT LEFT REAR WINDOW DRIVER UP
8 Q23 14RD/WT LEFT REAR WINDOW DRIVER DOWN
9 Q27 14RD/BK LEFT REAR WINDOW DRIVER DOWN
10 Q13 14DB LEFT REAR WINDOW DRIVER UP
REAR WHEEL SPEED SENSOR - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 B2 18YL REAR WHEEL SPEED SENSOR 12 VOLT SUPPLY
2 B1 18YL/DB REAR WHEEL SPEED SENSOR SIGNAL
REAR WIPER MOTOR - BLACK 6 WAY
CAV CIRCUIT FUNCTION
1 Z235 18BK GROUND
2 V21 20DB/RD REAR WIPER ON DRIVER
3 G80 20YL/WT FLIP-UP GLASS AJAR SWITCH SENSE
4 V22 20BR/YL REAR WIPER INTERMITTENT DRIVER
5 F70 18PK/BK FUSED B(+)
6- -
RED BRAKE WARNING INDICATOR SWITCH - GRAY 2 WAY
CAV CIRCUIT FUNCTION
1 G11 18WT/BK RED BRAKE WARNING INDICATOR DRIVER
2 Z142 18BK/WT GROUND
REMOTE KEYLESS ENTRY MODULE (EXCEPT BASE)-6WAY
CAV CIRCUIT FUNCTION
1 Y60 RKE DATA
2 Y62 RKE SUPPLY
3 Y61 RKE PROGRAM
4 Y63 RKE GROUND
5 Y64 RKE ANTENNA (+)
6 Y65 RKE ANTENNA (-)
8Wa - 80 - 86 8W-80 CONNECTOR PIN-OUTSKJ

CONNECTOR NAME/NUMBER COLOR LOCATION FIG.
Output Speed Sensor BK Left Side of Transmission 5
Overhead Map/Courtesy Lamp BK Overhead Console N/S
Oxygen Sensor 1/1 Upstream (2.4L) BK Right Side of Engine 12
Oxygen Sensor 1/1 Upstream (3.7L) BK Lower Left Side of Engine 3
Oxygen Sensor 1/2 Downstream
(2.4L)NAT Right Side of Transmission 11, 12
Oxygen Sensor 1/2 Downstream
(3.7L)NAT Left Side of Transmission 5, 7
Oxygen Sensor 2/1 Upstream (3.7L) BK Lower Right Side of Engine 4
Oxygen Sensor 2/2 Downstream
(3.7L)NAT Right Side of Transmission 6
Park Brake Switch BK Center Console 36, 40
Passenger Airbag YL Right Side Instrument Panel N/S
Passenger Seat Belt Switch LG At Passenger Seat N/S
Power Mirror Switch WT In Left Front Door 41
Power Outlet RD Center of Instrument Panel N/S
Power Steering Pressure Switch BK Left Front Side of Engine 3, 15
Power Window Master Switch LG Center Console 36, 40
Powertrain Control Module C1 (2.4L) BK At Powertrain Control Module 13, 14
Powertrain Control Module C1 (3.7L) BK At Powertrain Control Module 8, 9, 10
Powertrain Control Module C2 WT At Powertrain Control Module 8, 9, 10, 13, 14
Powertrain Control Module C3 GY At Powertrain Control Module 31
Radiator Fan Motor BK Right Front Side of Engine
Compartment28
Radiator Fan Relay BK Left Front Side of Engine
Compartment29
Radio C1 GY Rear of Radio N/S
Radio C2 Rear of Radio N/S
Radio C3 Rear of Radio N/S
Radio Choke GY Center of Instrument Panel N/S
Rear Map/Reading Lamp BK Overhead Console N/S
Rear Power Outlet RD Right Rear Quarter Panel 44, 45, 48
Rear Power Window Switch WT Center Console 36, 40
Rear Wheel Speed Sensor BK On Rear Axle N/S
Rear Window Defogger BK At Rear Window 46
Rear Wiper Motor BK In Tailgate 46
Red Brake Warning Indicator Switch
(LHD)GY Left Rear Side of Engine
Compartment31
Red Brake Warning Indicator Switch
(RHD)GY Right Rear Side of Engine
Compartment26
Right Curtain Airbag YL Right Mid B-Pillar 34, 39
Right Cylinder Lock Switch (Except
Base)LG In Right Front Door 41
KJ8W-91 CONNECTOR/GROUND/SPLICE LOCATION8Wa-91-7
CONNECTOR/GROUND/SPLICE LOCATION (Continued)

Possible indications of the cylinder head gasket
leaking between adjacent cylinders are:
²Loss of engine power
²Engine misfiring
²Poor fuel economy
Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
²Engine overheating
²Loss of coolant
²Excessive steam (white smoke) emitting from
exhaust
²Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test (Refer
to 9 - ENGINE - DIAGNOSIS AND TESTING). An
engine cylinder head gasket leaking between adja-
cent cylinders will result in approximately a 50±70%
reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING WITH COOLANT PRES-
SURE CAP REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure
cap. Start the engine and allow it to warm up until
thermostat opens.
If a large combustion/compression pressure leak
exists, bubbles will be visible in the coolant.
COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE PRESSURE BUILT UP, BY CONTINUOUS
ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to
pressure cap neck. Start the engine and observe the
tester's pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also
be checked by using Bloc-Chek Kit C-3685-A or
equivalent. Perform test following the procedures
supplied with the tool kit.
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Raise the vehicle on a hoist.
(3) Disconnect the exhaust pipe at the left side
exhaust manifold.
(4) Drain the engine coolant. Refer to COOLING
SYSTEM.
(5) Lower the vehicle.
(6) Remove the intake manifold. Refer to proce-
dure in this section.
(7) Remove the cylinder head cover. Refer to proce-
dure in this section.
(8) Remove the fan shroud and fan blade assembly.
Refer to COOLING SYSTEM.
(9) Remove accessory drive belt. Refer to COOL-
ING SYSTEM.
(10) Remove the power steering pump and set
aside.
(11) Rotate the crankshaft until the damper timing
mark is aligned with TDC indicator mark (Fig. 4).
(12) Verify the V6 mark on the camshaft sprocket
is at the 12 o'clock position (Fig. 5). Rotate the crank-
shaft one turn if necessary.
(13) Remove the crankshaft damper. Refer to Pro-
cedure.
(14) Remove the timing chain cover. Refer to pro-
cedure.
Fig. 4 Engine Top Dead Center
1 - TIMING CHAIN COVER
2 - CRANKSHAFT TIMING MARKS
9 - 20 ENGINE - 3.7LKJ
CYLINDER HEAD - LEFT (Continued)

(9) Using Special Tool 8516 Valve Spring Compres-
sor, install the rocker arms and the hydraulic lash
adjusters.
(10) Install the cylinder head cover. Refer to Cylin-
der Head Cover in this Section.
CYLINDER HEAD - RIGHT
DESCRIPTION
DESCRIPTION - CYLINDER HEAD
The cylinder heads are made of an aluminum alloy.
The cylinder head features two valves per cylinder
with pressed in powdered metal valve guides. The
cylinder heads also provide enclosures for the timing
chain drain, necessitating unique left and right cylin-
der heads.
DESCRIPTION - VALVE GUIDES
The valve guides are made of powered metal and
are pressed into the cylinder head. The guides are
not replaceable or serviceable, and valve guide ream-
ing is not recommended. If the guides are worn
beyond acceptable limits, replace the cylinder heads.
DESCRIPTION
The valves are made of heat resistant steel and
have chrome plated stems to prevent scuffing. Each
valve is actuated by a roller rocker arm which pivots
on a stationary lash adjuster. All valves use three
bead lock keepers to retain the springs and promote
valve rotation.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - HYDRAULIC LASH
ADJUSTER
A tappet-like noise may be produced from several
items. Check the following items.
(1) Engine oil level too high or too low. This may
cause aerated oil to enter the adjusters and cause
them to be spongy.
(2) Insufficient running time after rebuilding cylin-
der head. Low speed running up to 1 hour may be
required.
(3) Turn engine off and let set for a few minutes
before restarting. Repeat this several times after
engine has reached normal operating temperature.
(4) Low oil pressure.
(5) The oil restrictor in cylinder head gasket or the
oil passage to the cylinder head is plugged with
debris.(6) Air ingested into oil due to broken or cracked
oil pump pick up.
(7) Worn valve guides.
(8) Rocker arm ears contacting valve spring
retainer.
(9) Rocker arm loose, adjuster stuck or at maxi-
mum extension and still leaves lash in the system.
(10) Oil leak or excessive cam bore wear in cylin-
der head.
(11) Faulty lash adjuster.
²Check lash adjusters for sponginess while
installed in cylinder head and cam on camshaft at
base circle. Depress part of rocker arm over adjuster.
Normal adjusters should feel very firm. Spongy
adjusters can be bottomed out easily.
²Remove suspected lash adjusters, and replace.
²Before installation, make sure adjusters are at
least partially full of oil. This can be verified by little
or no plunger travel when lash adjuster is depressed.
DIAGNOSIS AND TESTING - CYLINDER HEAD
GASKET
A cylinder head gasket leak can be located between
adjacent cylinders or between a cylinder and the
adjacent water jacket.
Possible indications of the cylinder head gasket
leaking between adjacent cylinders are:
²Loss of engine power
²Engine misfiring
²Poor fuel economy
Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
²Engine overheating
²Loss of coolant
²Excessive steam (white smoke) emitting from
exhaust
²Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test (Refer
to 9 - ENGINE - DIAGNOSIS AND TESTING). An
engine cylinder head gasket leaking between adja-
cent cylinders will result in approximately a 50±70%
reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING WITH COOLANT PRES-
SURE CAP REMOVED.
9 - 30 ENGINE - 3.7LKJ
VALVE SPRINGS (Continued)

VISUAL TEST METHOD
With the engine cool, remove the coolant pressure
cap. Start the engine and allow it to warm up until
thermostat opens.
If a large combustion/compression pressure leak
exists, bubbles will be visible in the coolant.
COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE PRESSURE BUILT UP, BY CONTINUOUS
ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to
pressure cap neck. Start the engine and observe the
tester's pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also
be checked by using Bloc-Chek Kit C-3685-A or
equivalent. Perform test following the procedures
supplied with the tool kit.
REMOVAL
(1) Disconnect battery negative cable.
(2) Raise the vehicle on a hoist.
(3) Disconnect the exhaust pipe at the right side
exhaust manifold.
(4) Drain the engine coolant. Refer to COOLING
SYSTEM.
(5) Lower the vehicle.
(6) Remove the intake manifold. Refer to proce-
dure.
(7) Remove the cylinder head cover. Refer to proce-
dure.
(8) Remove the fan shroud. Refer to COOLING
SYSTEM.
(9) Remove oil fill housing from cylinder head.
(10) Remove accessory drive belt. Refer to COOL-
ING SYSTEM.
(11) Rotate the crankshaft until the damper timing
mark is aligned with TDC indicator mark.
(12) Verify the V6 mark on the camshaft sprocket
is at the 12 o'clock position. Rotate the crankshaft
one turn if necessary.
(13) Remove the crankshaft damper. Refer to pro-
cedure.
(14) Remove the timing chain cover. Refer to pro-
cedure.
(15) Lock the secondary timing chains to the idler
sprocket using Special Tool 8429 Timing Chain Hold-
ing Fixture.NOTE: Mark the secondary timing chain prior to
removal to aid in installation.
(16) Mark the secondary timing chain, one link on
each side of the V6 mark on the camshaft drive gear.
(17) Remove the right side secondary chain ten-
sioner. Refer to Timing Chain and Sprockets in this
section.
(18) Remove the cylinder head access plug.
(19) Remove the right side secondary chain guide.
Refer to Timing Chain and Sprockets in this section.
CAUTION: The nut on the right side camshaft
sprocket should not be removed for any reason, as
the sprocket and camshaft sensor target wheel is
serviced as an assembly. If the nut was removed
retorque nut to 5 N´m (44 in. lbs.).
(20) Remove the retaining bolt and the camshaft
drive gear.
CAUTION: Do not allow the engine to rotate. severe
damage to the valve train can occur.
CAUTION: Do not overlook the four smaller bolts at
the front of the cylinder head. Do not attempt to
remove the cylinder head without removing these
four bolts.
CAUTION: Do not hold or pry on the camshaft tar-
get wheel for any reason. A damaged target wheel
can result in a vehicle no start condition.
NOTE: The cylinder head is attached to the cylinder
block with twelve bolts.
(21) Remove the cylinder head retaining bolts.
(22) Remove the cylinder head and gasket. Discard
the gasket.
CAUTION: Do not lay the cylinder head on its gas-
ket sealing surface, do to the design of the cylinder
head gasket any distortion to the cylinder head
sealing surface may prevent the gasket from prop-
erly sealing resulting in leaks.
CLEANING
To ensure engine gasket sealing, proper surface
preparation must be performed, especially with the
use of aluminum engine components (Fig. 22). (Refer
to 9 - ENGINE - STANDARD PROCEDURE)
KJENGINE - 3.7L 9 - 31
CYLINDER HEAD - RIGHT (Continued)

DIAGNOSIS AND TESTING - REAR SEAL AREA
LEAKS
Since it is sometimes difficult to determine the
source of an oil leak in the rear seal area of the
engine, a more involved inspection is necessary. The
following steps should be followed to help pinpoint
the source of the leak.
If the leakage occurs at the crankshaft rear oil seal
area:
(1) Disconnect the battery.
(2) Raise the vehicle.
(3) Remove torque converter or clutch housing
cover and inspect rear of block for evidence of oil.
Use a black light to check for the oil leak:
(a) Circular spray pattern generally indicates
seal leakage or crankshaft damage.
(b) Where leakage tends to run straight down,
possible causes are a porous block, camshaft bore
cup plugs, oil galley pipe plugs, oil filter runoff,
and main bearing cap to cylinder block mating sur-
faces. See Engine, for proper repair procedures of
these items.
(4) If no leaks are detected, pressurized the crank-
case as outlined in the section, Inspection (Engine oil
Leaks in general)
CAUTION: Do not exceed 20.6 kPa (3 psi).(5) If the leak is not detected, very slowly turn the
crankshaft and watch for leakage. If a leak is
detected between the crankshaft and seal while
slowly turning the crankshaft, it is possible the
crankshaft seal surface is damaged. The seal area on
the crankshaft could have minor nicks or scratches
that can be polished out with emery cloth.
CAUTION: Use extreme caution when crankshaft
polishing is necessary to remove minor nicks or
scratches. The crankshaft seal flange is specially
machined to complement the function of the rear oil
seal.
(6) For bubbles that remain steady with shaft
rotation, no further inspection can be done until dis-
assembled. (Refer to 9 - ENGINE - DIAGNOSIS AND
TESTING), under the Oil Leak row, for components
inspections on possible causes and corrections.
(7) After the oil leak root cause and appropriate
corrective action have been identified, (Refer to 9 -
ENGINE/ENGINE BLOCK/CRANKSHAFT OIL
SEAL - REAR - REMOVAL).
OIL
STANDARD PROCEDURE - ENGINE OIL
WARNING: NEW OR USED ENGINE OIL CAN BE
IRRITATING TO THE SKIN. AVOID PROLONGED OR
REPEATED SKIN CONTACT WITH ENGINE OIL.
CONTAMINANTS IN USED ENGINE OIL, CAUSED BY
INTERNAL COMBUSTION, CAN BE HAZARDOUS TO
YOUR HEALTH. THOROUGHLY WASH EXPOSED
SKIN WITH SOAP AND WATER. DO NOT WASH
SKIN WITH GASOLINE, DIESEL FUEL, THINNER, OR
SOLVENTS, HEALTH PROBLEMS CAN RESULT. DO
NOT POLLUTE, DISPOSE OF USED ENGINE OIL
PROPERLY.
ENGINE OIL SPECIFICATION
CAUTION: Do not use non-detergent or straight
mineral oil when adding or changing crankcase
lubricant. Engine failure can result.
API SERVICE GRADE CERTIFIED
Use an engine oil that is API Service Grade Certi-
fied. MOPARtprovides engine oils that conform to
this service grade.
SAE VISCOSITY
An SAE viscosity grade is used to specify the vis-
cosity of engine oil. Use only engine oils with multi-
Fig. 70 Oil Pressure Sending Unit -Typical
1 - BELT
2 - OIL PRESSURE SENSOR
3 - OIL FILTER
4 - ELEC. CONNECTOR
KJENGINE - 3.7L 9 - 61
LUBRICATION (Continued)

ple viscosities such as 5W-30 or 10W-30 in the 3.7L
engines. These are specified with a dual SAE viscos-
ity grade which indicates the cold-to-hot temperature
viscosity range. Select an engine oil that is best
suited to your particular temperature range and vari-
ation (Fig. 71).
ENERGY CONSERVING OIL
An Energy Conserving type oil is recommended for
gasoline engines. The designation of ENERGY CON-
SERVING is located on the label of an engine oil con-
tainer.
CONTAINER IDENTIFICATION
Standard engine oil identification notations have
been adopted to aid in the proper selection of engine
oil. The identifying notations are located on the label
of engine oil plastic bottles and the top of engine oil
cans (Fig. 72).
OIL LEVEL INDICATOR (DIPSTICK)
The engine oil level indicator is located on the
right side of the the 3.7L engine.
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil,
pressure loss or oil foaming can result.Inspect engine oil level approximately every 800
kilometers (500 miles). Unless the engine has exhib-
ited loss of oil pressure, run the engine for about five
minutes before checking oil level. Checking engine oil
level on a cold engine is not accurate.
To ensure proper lubrication of an engine, the
engine oil must be maintained at an acceptable level.
The acceptable levels are indicated between the ADD
and SAFE marks on the engine oil dipstick.
(1) Position vehicle on level surface.
(2) With engine OFF, allow approximately ten min-
utes for oil to settle to bottom of crankcase, remove
engine oil dipstick.
(3) Wipe dipstick clean.
(4) Install dipstick and verify it is seated in the
tube.
(5) Remove dipstick, with handle held above the
tip, take oil level reading.
(6) Add oil if level is below the SAFE ZONE on
dipstick.
ENGINE OIL CHANGE
Change engine oil at mileage and time intervals
described in Maintenance Schedules.
Run engine until achieving normal operating tem-
perature.
(1) Position the vehicle on a level surface and turn
engine off.
(2) Remove oil fill cap.
(3) Hoist and support vehicle on safety stands.
(4) Place a suitable drain pan under crankcase
drain.
(5) Remove drain plug from crankcase and allow
oil to drain into pan. Inspect drain plug threads for
stretching or other damage. Replace drain plug if
damaged.
(6) Install drain plug in crankcase.
(7) Remove oil filter (Refer to 9 - ENGINE/LUBRI-
CATION/OIL FILTER - REMOVAL).
(8) Install a new oil filter.
(9) Lower vehicle and fill crankcase with 5 quarts
of the specified type of engine oil described in this
section.
(10) Install oil fill cap.
(11) Start engine and inspect for leaks.
(12) Stop engine and inspect oil level.
USED ENGINE OIL DISPOSAL
Care should be exercised when disposing used
engine oil after it has been drained from a vehicle
engine. Refer to the WARNING at beginning of this
section.
Fig. 71 Temperature/Engine Oil Viscosity - 3.7L
Engine
Fig. 72 Engine Oil Container Standard Notations
9 - 62 ENGINE - 3.7LKJ
OIL (Continued)

INTAKE MANIFOLD
DESCRIPTION
The intake manifold (Fig. 86) is made of a compos-
ite material and features 300 mm (11.811 in.) long
runners which maximizes low end torque. The intake
manifold uses single plane sealing which consist of
six individual press in place port gaskets to prevent
leaks. The throttle body attaches directly to the
intake manifold. Eight studs and two bolts are used
to fasten the intake to the head.
DIAGNOSIS AND TESTING - INTAKE
MANIFOLD LEAKS
An intake manifold air leak is characterized by
lower than normal manifold vacuum. Also, one or
more cylinders may not be functioning.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR THE FAN.
DO NOT WEAR LOOSE CLOTHING.
(1) Start the engine.
(2) Spray a small stream of water (Spray Bottle) at
the suspected leak area.
(3) If engine RPM'S change, the area of the sus-
pected leak has been found.
(4) Repair as required.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove resonator assembly and air inlet hose.
(3) Disconnect throttle and speed control cables.
(4) Disconnect electrical connectors for the follow-
ing components: Refer to FUEL SYSTEM for compo-
nent locations.
²Manifold Absolute Pressure (MAP) Sensor
²Intake Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Coolant Temperature (CTS) Sensor
²Idle Air Control (IAC) Motor
(5) Disconnect vapor purge hose, brake booster
hose, speed control servo hose, positive crankcase
ventilation (PCV) hose.
(6) Disconnect generator electrical connections.
(7) Disconnect air conditioning compressor electri-
cal connections.
(8) Disconnect left and right radio suppressor
straps.
(9) Disconnect and remove ignition coil towers.
(10) Remove top oil dipstick tube retaining bolt
and ground strap.
Fig. 85 Oil Pump and Primary Timing Chain
Tensioner Tightening Sequence
Fig. 86 INTAKE MANIFOLD
1 - THROTTLE BODY
2 - INTAKE MANIFOLD
3 - INTAKE PORT GASKETS
9 - 68 ENGINE - 3.7LKJ
OIL PUMP (Continued)

ENGINE - 2.4L
DESCRIPTION
The 2.4 Liter (148 cu. in.) in-line four cylinder
engine is a double over head camshaft with hydraulic
lifters and four valve per cylinder design. The engine
is free-wheeling; meaning it has provisions for piston-
to-valve clearance. However valve-to-valve interference
can occur, if camshafts are rotated independently.
The cylinders are numbered from front of the
engine to the rear. The firing order is 1±3±4±2.
The engine identification number is located on the
rear of the cylinder block (Fig. 1).
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE TEST
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
²Exhaust and intake valve leaks (improper seat-
ing).
²Leaks between adjacent cylinders or into water
jacket.
²Any causes for combustion/compression pressure
loss.WARNING: DO NOT REMOVE THE PRESSURE CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM COOLANT CAN
OCCUR.
Check the coolant level and fill as required. DO
NOT install the pressure cap.
Start and operate the engine until it attains nor-
mal operating temperature, then turn the engine
OFF.
Clean spark plug recesses with compressed air.
Remove the spark plugs.
Remove the oil filler cap.
Remove the air cleaner.
Calibrate the tester according to the manufactur-
er's instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1,379
kPa (200 psi) maximum, with 552 kPa (80 psi) rec-
ommended.
Perform the test procedures on each cylinder
according to the tester manufacturer's instructions.
While testing, listen for pressurized air escaping
through the throttle body, tailpipe and oil filler cap
opening. Check for bubbles in the coolant.
All gauge pressure indications should be equal,
with no more than 25% leakage per cylinder.
FOR EXAMPLE:At 552 kPa (80 psi) input pres-
sure, a minimum of 414 kPa (60 psi) should be main-
tained in the cylinder.
DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE TEST
The results of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise the indicated compression pressures may
not be valid for diagnosis purposes.
(1) Check engine oil level and add oil if necessary.
(2) Drive the vehicle until engine reaches normal
operating temperature. Select a route free from traf-
fic and other forms of congestion, observe all traffic
laws, and accelerate through the gears several times
briskly.
(3) Remove all spark plugs from engine. As spark
plugs are being removed, check electrodes for abnor-
mal firing indicators fouled, hot, oily, etc. Record cyl-
inder number of spark plug for future reference.
(4) Remove the Auto Shutdown (ASD) relay from
the PDC.
(5) Be sure throttle blade is fully open during the
compression check.
(6) Insert compression gage adaptor Special Tool
8116 or the equivalent, into the #1 spark plug hole in
cylinder head. Connect the 0±500 psi (Blue) pressure
transducer with cable adaptors to the DRBIIIt.
Fig. 1 ENGINE IDENTIFICATION
1 - ENGINE IDENTIFICATION
KJENGINE9s-3