2002 JEEP LIBERTY Ignition coil

COIL ON PLUG NO. 5 (3.7L) - BLACK 3 WAY
CAV CIRCUIT FUNCTION
1 K95 14TN/DG COIL ON PLUG DRIVER NO. 5
2 A142 14DG/OR AUTO SHUT DOWN RELAY OUTPUT
3- -
COIL ON PLUG NO. 6 (3.7L) - BLACK 3 WAY
CAV CIRCUIT FUNCTION
1 K96 14TN/LB COIL ON PLUG DRIVER NO. 6
2 A142 14DG/OR AUTO SHUT DOWN RELAY OUTPUT
3- -
COIL RAIL (2.4L) - BLACK 3 WAY
CAV CIRCUIT FUNCTION
1 K17 18DB/TN IGNITION COIL DRIVER NO. 2
2 A142 14DG/OR AUTO SHUT DOWN RELAY OUTPUT
3 K19 18BK/GY IGNITION COIL DRIVER NO. 1
COMPASS MINI-TRIP COMPUTER (PREMIUM) - BLACK 6 WAY
CAV CIRCUIT FUNCTION
1- -
2 D25 20YL/VT PCI BUS
3 M1 20PK FUSED B(+)
4 Z2 20BK/LG CLEAN GROUND
5 F87 20WT/BK FUSED IGNITION SWITCH OUTPUT (RUN-START)
6- -
KJ8W-80 CONNECTOR PIN-OUTS8Wa-80-51

POWER WINDOW MASTER SWITCH (MIDLINE/HIGHLINE) - LT. GRAY 14 WAY
CAV CIRCUIT FUNCTION
1- -
2 Q1 16YL POWER WINDOW SWITCH FEED
2 Q1 16YL POWER WINDOW SWITCH FEED
3- -
4 Q27 14RD/BK LEFT REAR WINDOW DRIVER DOWN
5 Q17 14DB/WT LEFT REAR WINDOW DRIVER UP
6 Q28 14DG/WT RIGHT REAR WINDOW DRIVER DOWN
7 Q18 14GY/BK RIGHT REAR WINDOW DRIVER UP
8- -
9 Q21 14WT LEFT FRONT WINDOW DRIVER DOWN
10 F81 12TN FUSED B(+)
11 Q11 14LB LEFT FRONT WINDOW DRIVER UP
12 Q12 14BR RIGHT FRONT WINDOW DRIVER UP
13 Q22 14VT/WT RIGHT FRONT WINDOW DRIVER DOWN
14 Z238 12BK/WT GROUND
POWERTRAIN CONTROL MODULE-C1 (2.4L) - BLACK 32 WAY
CAV CIRCUIT FUNCTION
1- -
2 F1 18DB FUSED IGNITION SWITCH OUTPUT (RUN-START)
3- -
4 K4 18BK/LB SENSOR GROUND
5- -
6- -
7 K19 18BK/GY IGNITION COIL NO. 1 DRIVER
8 K24 18GY/BK CRANKSHAFT POSITION SENSOR SIGNAL
9- -
10 K60 18YL/BK IDLE AIR CONTROL NO. 2 DRIVER
11 K40 18BR/WT IDLE AIR CONTROL NO. 1 DRIVER
12 K10 18DB/OR POWER STEERING PRESSURE SWITCH SENSE
13 - -
14 K77 18BR/WT TRANSFER CASE POSITION SENSOR INPUT
15 K21 18BK/RD INTAKE AIR TEMPERATURE SENSOR SIGNAL
16 K2 18TN/BK ENGINE COOLANT TEMPERATURE SENSOR SIGNAL
17 K7 18OR 5 VOLT SUPPLY
18 K44 18TN/YL CAMSHAFT POSITION SENSOR SIGNAL
19 K39 18GY/RD IDLE AIR CONTROL NO. 3 DRIVER
20 K59 18VT/BK IDLE AIR CONTROL NO. 4 DRIVER
21 - -
22 A14 16RD/WT FUSED B(+)
23 K22 18OR/DB THROTTLE POSITION SENSOR SIGNAL
24 K41 18BK/DG OXYGEN SENSOR 1/1 SIGNAL
25 K141 18TN/WT OXYGEN SENSOR 1/2 SIGNAL
26 - -
27 K1 18DG/RD MANIFOLD ABOLUTE PRESSURE SENSOR SIGNAL
28 - -
29 - -
30 - -
31 Z107 14BK/DB GROUND
32 Z107 14BK/DB GROUND
KJ8W-80 CONNECTOR PIN-OUTS8Wa-80-81

POWERTRAIN CONTROL MODULE-C1 (3.7L) - BLACK 32 WAY
CAV CIRCUIT FUNCTION
1 K93 14TN/OR COIL ON PLUG DRIVER NO. 3
2 F1 18DB FUSED IGNITION SWITCH OUTPUT (RUN-START)
3 K94 14TN/LG COIL ON PLUG DRIVER NO. 4
4 K4 18BK/LB SENSOR GROUND
5 K96 14TN/LB COIL ON PLUG DRIVER NO. 6
6 T41 18BK/WT (A/T) PARK/NEUTRAL POSITION SWITCH SENSE
7 K91 14TN/RD COIL ON PLUG DRIVER NO.1
8 K24 18GY/BK CRANKSHAFT POSITION SENSOR SIGNAL
9- -
10 K60 18YL/BK IDLE AIR CONTROL NO. 2 DRIVER
11 K40 18BR/WT IDLE AIR CONTROL NO. 1 DRIVER
12 K10 18DB/OR POWER STEERING PRESSURE SWITCH SENSE
13 T141 18 YL/RD (M/T) FUSED IGNITION SWITCH OUTPUT (START)
13 F45 18YL/BR (A/T) FUSED IGNITION SWITCH OUTPUT (START)
14 K77 18BR/WT TRANSFER CASE POSITION SENSOR INPUT
15 K21 18BK/RD INTAKE AIR TEMPERATURE SENSOR SIGNAL
16 K2 18TN/BK ENGINE COOLANT TEMPERATURE SENSOR SIGNAL
17 K7 18OR 5 VOLT SUPPLY
18 K44 18TN/YL CAMSHAFT POSITION SENSOR SIGNAL
19 K39 18GY/RD IDLE AIR CONTROL NO. 3 DRIVER
20 K59 18VT/BK IDLE AIR CONTROL NO. 4 DRIVER
21 K95 14TN/DG COIL ON PLUG DRIVER NO. 5
22 A14 16RD/WT FUSED B(+)
23 K22 18OR/DB THROTTLE POSITION SENSOR SIGNAL
24 K41 18BK/DG OXYGEN SENSOR 1/1 SIGNAL
25 K141 18TN/WT OXYGEN SENSOR 1/2 SIGNAL
26 K241 18LG/RD OXYGEN SENSOR 2/1 SIGNAL
27 K1 18DG/RD MANIFOLD ABOLUTE PRESSURE SENSOR SIGNAL
28 - -
29 K341 18TN/WT OXYGEN SENSOR 2/2 SIGNAL
30 - -
31 Z107 14BK/DB GROUND
32 Z107 14BK/DB GROUND
POWERTRAIN CONTROL MODULE-C2 (GAS) - WHITE 32 WAY
CAV CIRCUIT FUNCTION
1- -
2- -
3- -
4 K11 18WT/DB FUEL INJECTOR NO. 1 DRIVER
5 K13 18YL/WT FUEL INJECTOR NO. 3 DRIVER
6 K38 18GY (3.7L) FUEL INJECTOR NO. 5 DRIVER
7- -
8- -
9 K92 14TN/PK (3.7L) COIL ON PLUG DRIVER NO. 2
9 K17 18DB/TN (2.4L) IGNITION COIL NO. 2 DRIVER
10 K20 18DG GENERATOR FIELD
11 - -
12 K58 18BR/DB (3.7L) FUEL INJECTOR NO. 6 DRIVER
8Wa - 80 - 82 8W-80 CONNECTOR PIN-OUTSKJ

DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - INTRODUCTION
Engine diagnosis is helpful in determining the
causes of malfunctions not detected and remedied by
routine maintenance.
These malfunctions may be classified as either per-
formance (e.g., engine idles rough and stalls) or
mechanical (e.g., a strange noise).
(Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING)ÐPERFORMANCE and (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)ÐMECHANICAL for
possible causes and corrections of malfunctions.
(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY -
DIAGNOSIS AND TESTING) and (Refer to 14 -
FUEL SYSTEM/FUEL INJECTION - DIAGNOSIS
AND TESTING) for the fuel system diagnosis.Additional tests and diagnostic procedures may be
necessary for specific engine malfunctions that can
not be isolated with the Service Diagnosis charts.
Information concerning additional tests and diagno-
sis is provided within the following diagnosis:
²Cylinder Compression Pressure Test (Refer to 9 -
ENGINE - DIAGNOSIS AND TESTING).
²Cylinder Combustion Pressure Leakage Test
(Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING).
²Engine Cylinder Head Gasket Failure Diagnosis
(Refer to 9 - ENGINE/CYLINDER HEAD - DIAGNO-
SIS AND TESTING).
²Intake Manifold Leakage Diagnosis (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
DIAGNOSIS AND TESTING).
DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - PERFORMANCE
CONDITION POSSIBLE CAUSE CORRECTION
ENGINE WILL NOT START 1. Weak battery 1. Charge or replace as necessary.
2. Corroded or loose battery
connections.2. Clean and tighten battery
connections. Apply a coat of light
mineral grease to the terminals.
3. Faulty starter. 3. (Refer to 8 - ELECTRICAL/
STARTING - DIAGNOSIS AND
TESTING).
4. Faulty coil or control unit. 4. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL).
5. Incorrect spark plug gap. 5. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG
- CLEANING).
6. Incorrect right bank cam timing. 6. Refer to engine timing in this
section.
7. Dirt or water in fuel system. 7. Clean system and replace fuel
filter.
8.Faulty fuel pump, relay or wiring. 8.Repair or replace as necessary.
9. Faulty cam or crank sensor 9. Refer to Ignition system.
ENGINE STALLS OR ROUGH IDLE 1. Vacuum leak. 1. Inspect intake manifold and
vacuum hoses, repair or replace as
necessary.
2. Faulty crank position sensor 2. Replace crank position sensor.
4. Faulty coil. 4. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL).
9 - 4 ENGINE - 3.7LKJ
ENGINE - 3.7L (Continued)

CONDITION POSSIBLE CAUSE CORRECTION
5. Incorrect cam timing. 5. (Refer to 9 - ENGINE/VALVE
TIMING - STANDARD
PROCEDURE).
1. ENGINE LOSS OF POWER 1. Dirty or incorrectly gapped spark
plugs.1. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG
- CLEANING).
2. Dirt or water in fuel system. 2. Clean system and replace fuel
filter.
3. Faulty fuel pump. 3. (Refer to 14 - FUEL SYSTEM/
FUEL DELIVERY/FUEL PUMP -
DIAGNOSIS AND TESTING).
4. Blown cylinder head gasket. 4. Replace cylinder head gasket.
5. Low compression. 5. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING), repair
as necessary.
6. Burned, warped or pitted valves. 6. Replace as necessary.
7. Plugged or restricted exhaust
system.7. Inspect and replace as
necessary.
8. Faulty coil. 8. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL).
9. Incorrect cam timing. 9. Refer to Engine TIming in this
section.
1. ENGINE MISSES ON
ACCELERATION1. Spark plugs dirty or incorrectly
gapped.1. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG
- CLEANING).
2. Dirt in fuel system. 2. Clean fuel system.
3. Burned, warped or pitted valves. 3. Replcae as necessary.
4. Faulty coil. 4. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL).
1. ENGINE MISSES AT HIGH
SPEED1. Spark plugs dirty or incorrectly
gapped.1. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG
- CLEANING).
2. Faulty coil. 2. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL).
3. Dirt or water in fuel system. 3. Clean system and replace fuel
filter.
KJENGINE - 3.7L 9 - 5
ENGINE - 3.7L (Continued)

(6) Position the camshaft drive gear into the tim-
ing chain aligning the V6 mark between the two
marked chain links (Two links marked during remov-
al).
(7) Using Special Tool 8428 Camshaft Wrench,
rotate the camshaft until the camshaft sprocket
dowel is aligned with the slot in the camshaft
sprocket. Install the sprocket onto the camshaft.
CAUTION: Remove excess oil from camshaft
sprocket bolt. Failure to do so can cause bolt over-
torque resulting in bolt failure.
(8) Remove excess oil from camshaft sprocket bolt,
then install the camshaft sprocket retaining bolt and
hand tighten.
(9) Remove timing chain wedge special tool 8379.
(10) Using Special Tool 6958 spanner wrench with
adapter pins 8346, torque the camshaft sprocket
retaining bolt to 122 N´m (90 ft. lbs.).
(11) Install the camshaft position sensor.
(12) Install the cylinder head cover.
CYLINDER HEAD COVER(S)
REMOVAL
(1) Disconnect battery negative cable.
(2) Remove air cleaner assembly, resonator assem-
bly and air inlet hose.
(3) Drain cooling system, below the level of the
heater hoses. Refer to COOLING SYSTEM.(4) Remove accessory drive belt.
(5) Remove air conditioning compressor retaining
bolts and move compressor to the left.
(6) Remove heater hoses.
(7) Disconnect injector and ignition coil connectors.
(8) Disconnect and remove positive crankcase ven-
tilation (PCV) hose.
(9) Remove oil fill tube.
(10) Un-clip injector and ignition coil harness and
move away from cylinder head cover.
(11) Remove right rear breather tube and filter
assembly.
(12) Remove cylinder head cover retaining bolts.
(13) Remove cylinder head cover.
INSTALLATION
CAUTION: Do not use harsh cleaners to clean the
cylinder head covers. Severe damage to covers
may occur.
NOTE: The gasket may be used again, provided no
cuts, tears, or deformation has occurred.
(1) Clean cylinder head cover and both sealing sur-
faces. Inspect and replace gasket as necessary.
(2) Tighten cylinder head cover bolts and double
ended studs to 12 N´m (105 in. lbs).
(3) Install right rear breather tube and filter
assembly.
(4) Connect injector, ignition coil electrical connec-
tors and harness retaining clips.
(5) Install the oil fill tube.
(6) Install PCV hose.
(7) Install heater hoses.
(8) Install air conditioning compressor retaining
bolts.
(9) Install accessory drive belt
(10) Fill Cooling system
(11) Install air cleaner assembly, resonator assem-
bly and air inlet hose.
(12) Connect battery negative cable.
INTAKE/EXHAUST VALVES &
SEATS
STANDARD PROCEDURE - REFACING
NOTE: Valve seats that are worn or burned can be
reworked, provided that correct angle and seat
width are maintained. Otherwise the cylinder head
must be replaced.
Fig. 23 Camshaft Bearing Caps Tightening
Sequence
9 - 34 ENGINE - 3.7LKJ
CAMSHAFT(S) (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)

(11) Bleed fuel system. Refer to FUEL SYSTEM.
(12) Remove fuel rail.
(13) Remove throttle body assembly and mounting
bracket.
(14) Drain cooling system below coolant tempera-
ture level. Refer to COOLING SYSTEM.
(15) Remove the heater hoses from the engine
front cover and the heater core.
(16) Unclip and remove heater hoses and tubes
from intake manifold.
(17) Remove coolant temperature sensor. Refer to
FUEL SYSTEM.
(18) Remove intake manifold retaining fasteners in
reverse order of tightening sequence.
(19) Remove intake manifold.
INSTALLATION
(1) Install intake manifold gaskets.
(2) Install intake manifold.
(3) Install intake manifold retaining bolts and
tighten in sequence shown in to 12 N´m (105 in. lbs.).
(4) Install left and right radio suppressor straps.
(5) Install throttle body assembly.
(6) Install throttle cable bracket.
(7) Connect throttle cable and speed control cable
to throttle body.
(8) Install fuel rail.
(9) Install ignition coil towers.
(10) Position and install heater hoses and tubes
onto intake manifold.
(11) Install the heater hoses to the heater core and
engine front cover.
(12) Connect electrical connectors for the following
components:
²Manifold Absolute Pressure (MAP) Sensor
²Intake Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Coolant Temperature (CTS) Sensor
²Idle Air Control (IAC) Motor
²Ignition coil towers
²Fuel injectors
(13) Install top oil dipstick tube retaining bolt and
ground strap.
(14) Connect generator electrical connections.
(15) Connect Vapor purge hose, Brake booster
hose, Speed control servo hose, Positive crankcase
ventilation (PCV) hose.
(16) Fill cooling system.
(17) Install resonator assembly and air inlet hose.
(18) Connect negative cable to battery.
EXHAUST MANIFOLD
DESCRIPTION
The exhaust manifolds (Fig. 87) are log style with
a patented flow enhancing design to maximize perfor-
mance. The exhaust manifolds are made of high sili-
con molybdenum cast iron. A perforated core graphite
exhaust manifold gasket is used to improve sealing
to the cylinder head. The exhaust manifolds are cov-
ered by a three layer laminated heat shield for ther-
mal protection and noise reduction. The heat shields
(Fig. 88) are fastened with a torque prevailing nut
that is backed off slightly to allow for the thermal
expansion of the exhaust manifold.
REMOVAL
RIGHT EXHAUST MANIFOLD
(1) Disconnect the negative cable from the battery.
(2) Raise and support the vehicle.
(3) Remove the bolts and nuts attaching the
exhaust pipe to the engine exhaust manifold.
(4) Lower the vehicle.
(5) Remove the exhaust heat shield (Fig. 89).
(6) Remove bolts, nuts and washers attaching
manifold to cylinder head.
(7) Remove manifold and gasket from the cylinder
head.
Fig. 87 EXHAUST MANIFOLDS
1 - LEFT SIDE EXHAUST MANIFOLD
2 - RIGHT SIDE EXHAUST MANIFOLD
KJENGINE - 3.7L 9 - 69
INTAKE MANIFOLD (Continued)