2002 JEEP LIBERTY oil pressure

ENGINE COOLANT TEMPERATURE SENSOR (GAS) - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 K4 18BK/LB SENSOR GROUND
2 K2 18TN/BK ENGINE COOLANT TEMPERATURE SENSOR SIGNAL
ENGINE OIL PRESSURE SENSOR - BLACK 3 WAY
CAV CIRCUIT FUNCTION
1 K6 18VT/WT SENSOR REFERENCE VOLTAGE B
2 G60 20GY/YL (DIESEL) ENGINE OIL PRESSURE SENSOR SIGNAL
2 G60 18GY/YL (GAS) ENGINE OIL PRESSURE SENSOR SIGNAL
3 K4 18BK/LB SENSOR GROUND
EVAP/PURGE SOLENOID - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 K52 18PK/BK EVAP/PURGE SOLENOID CONTROL
2 F1 18DB FUSED IGNITION SWITCH OUTPUT (RUN-START)
FLIP-UP GLASS RELEASE MOTOR - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 Z235 18BK GROUND
2 P100 18OR/BR FLIP-UP GLASS RELEASE MOTOR DRIVER
FLIP-UP GLASS RELEASE SWITCH - WHITE 2 WAY
CAV CIRCUIT FUNCTION
1 G910 20VT/BR TAILGATE SWITCH GROUND
2 P101 20OR/PK FLIP-UP GLASS RELEASE SWITCH SENSE
8Wa - 80 - 58 8W-80 CONNECTOR PIN-OUTSKJ

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

POWERTRAIN CONTROL MODULE-C2 (GAS) - WHITE 32 WAY
CAV CIRCUIT FUNCTION
13 - -
14 - -
15 K12 18TN FUEL INJECTOR NO. 2 DRIVER
16 K14 18LB/BR FUEL INJECTOR NO. 4 DRIVER
17 K173 18LG RADIATOR FAN RELAY CONTROL
18 - -
19 C18 18DB A/C PRESSURE SIGNAL
20 - -
21 - -
22 - -
23 G60 18GY/YL ENGINE OIL PRESSURE SENSOR SIGNAL
24 - -
25 - -
26 - -
27 - -
28 - -
29 - -
30 - -
31 K6 18VT/WT 5 VOLT SUPPLY
32 - -
POWERTRAIN CONTROL MODULE-C3 (GAS) - LT. GRAY 32 WAY
CAV CIRCUIT FUNCTION
1 C13 18DG A/C COMPRESSOR CLUTCH RELAY CONTROL
2- -
3 K51 18DB/YL AUTO SHUT DOWN RELAY CONTROL
4 V36 18TN/RD SPEED CONTROL VACUUM SOLENOID CONTROL
5 V35 18LG/RD SPEED CONTROL VENT SOLENOID CONTROL
6 K90 18TN (M/T) CLUTCH INTERLOCK RELAY CONTROL
7 K42 18DB/LB (3.7L) KNOCK SENSOR NO. 1 SIGNAL
7 K42 18DB/LB (2.4L) NOT USED
8 K99 18BR/OR OXYGEN SENSOR 1/1 HEATER CONTROL
9 K512 18RD/YL OXYGEN SENSOR DOWNSTEAM RELAY CONTROL
10 K106 18WT/DG LEAK DETECTION PUMP SOLENOID CONTROL
11 V32 18YL/RD SPEED CONTROL SUPPLY
12 F142 18OR/DG FUSED AUTO SHUT DOWN RELAY SENSE INPUT
13 T10 18YL/DG TORQUE MANAGEMENT REQUEST SENSE
14 K107 18OR LEAK DETECTION PUMP SWITCH SENSE
15 K118 18PK/YL BATTERY TEMPERATURE SENSOR SIGNAL
16 K299 18BR/WT (2.4L) OXYGEN SENSOR 1/2 HEATER CONTROL
16 K299 18BR/WT (3.7L) OXYGEN SENSOR 2/1 HEATER CONTROL
17 B22 18DG/YL VEHICLE SPEED OUTPUT
18 K142 18GY/BK (2.4L) NOT USED
18 K142 18GY/BK (3.7L) KNOCK SENSOR NO. 2 SIGNAL
19 K31 18BR FUEL PUMP RELAY CONTROL
20 K52 18PK/BK EVAP PURGE/SOLENOID CONTROL
21 - -
22 C21 18DB/OR A/C SWITCH SENSE
23 - -
24 K29 18WT/PK BRAKE LAMP SWITCH SENSE
25 K125 18WT/DB GENERATOR SOURCE
KJ8W-80 CONNECTOR PIN-OUTS8Wa-80-83

CONNECTOR NAME/NUMBER COLOR LOCATION FIG.
Coil On Plug No.5 (3.7L) BK Left Side of Engine Near
Fuel Injector No.51
Coil On Plug No.6 (3.7L) BK Right Side of Engine Near
Fuel Injector No.62
Coil Rail (2.4L) BK Right Side of Engine 11, 12
Combination Flasher WT Under Left Side of
Instrument PanelN/S
Compass Mini-Trip Computer BK At Overhead Console N/S
Controller Antilock Brake BK Left Side of Engine
Compartment30
Crankshaft Position Sensor (2.4L) BK Top of Engine N/S
Crankshaft Position Sensor (3.7L) BK Right Lower Side of Engine 4
Crankshaft Position Sensor (Diesel) BK Right Rear Side of Engine 17
Data Link Connector BK Under Center of Instrument
PanelN/S
Diagnostic Junction Port BK Under Center of Instrument
Panel49
Dome Lamp (Base) BK On Headliner N/S
Driver Airbag Squib 1 GY In Steering Wheel N/S
Driver Airbag Squib 2 BK In Steering Wheel N/S
Driver Seat Belt Switch LG At Drive Seat N/S
Driver Seat Belt Tensioner (LHD) YL Lower Left B-Pillar 35
Driver Seat Belt Tensioner (RHD) YL Lower Right B-Pillar 39
EGR Solenoid Right Rear Side of Engine
Compartment27
Engine Control Module C1 BK Left Rear Side of Engine
Compartment19
Engine Control Module C2 BK Left Rear Side of Engine
Compartment19
Engine Coolant Level Sensor (Diesel) LG Rear Side of Engine
Compartment18
Engine Coolant Temperature Sensor
(Diesel)BK Left Side of Engine 20
Engine Coolant Temperature Sensor
(Gas)BK Front Side of Engine 2
Engine Oil Pressure Sensor (2.4L) BK Top of Engine N/S
Engine Oil Pressure Sensor (3.7L) BK Left Front Side of Engine 3
Engine Oil Pressure Sensor (Diesel) BK Right Rear Side of Engine 17
Engine Starter Motor Right Front Side of Engine 20
Evap/Purge Solenoid BK At Solenoid N/S
Flip-Up Glass Release Motor BK In Tailgate 46
Flip-Up Glass Release Switch WT In Tailgate 46
Front Washer Pump BK Right Front Side of Engine
Compartment28
Front Wiper Motor (LHD) BK Left Side of Cowl 24
8Wa - 91 - 4 8W-91 CONNECTOR/GROUND/SPLICE LOCATIONKJ
CONNECTOR/GROUND/SPLICE LOCATION (Continued)

ENGINE - 3.7L
TABLE OF CONTENTS
page page
ENGINE - 3.7L
DESCRIPTION..........................3
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - INTRODUCTION............4
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - PERFORMANCE............4
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - MECHANICAL..............6
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - LUBRICATION..............7
DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE..............8
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE.......8
STANDARD PROCEDURE
STANDARD PROCEDURE - ENGINE
GASKET SURFACE PREPARATION.........9
STANDARD PROCEDURE - REPAIR
DAMAGED OR WORN THREADS..........9
STANDARD PROCEDURE - ENGINE CORE
AND OIL GALLERY PLUGS..............10
REMOVAL.............................10
INSTALLATION.........................11
SPECIFICATIONS
TORQUE............................12
3.7L ENGINE.........................12
SPECIAL TOOLS
3.7L ENGINE.........................15
AIR CLEANER ELEMENT
REMOVAL - 3.7L........................19
INSTALLATION - 3.7L....................19
CYLINDER HEAD - LEFT
DESCRIPTION - VALVE GUIDES...........19
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - HYDRAULIC
LASH ADJUSTER.....................19
DIAGNOSIS AND TESTING - CYLINDER
HEAD GASKET.......................19
REMOVAL.............................20
CLEANING............................22
INSTALLATION.........................22
CAMSHAFT(S)
DESCRIPTION.........................23
REMOVAL.............................24
INSTALLATION.........................25
CYLINDER HEAD COVER(S)
DESCRIPTION.........................25
REMOVAL.............................25INSTALLATION.........................26
INTAKE/EXHAUST VALVES & SEATS
DESCRIPTION.........................26
STANDARD PROCEDURE - REFACING......26
REMOVAL.............................27
INSTALLATION.........................28
ROCKER ARM
DESCRIPTION.........................29
VALVE GUIDE SEALS
DESCRIPTION.........................29
VALVE SPRINGS
DESCRIPTION.........................29
REMOVAL.............................29
INSTALLATION.........................29
CYLINDER HEAD - RIGHT
DESCRIPTION
DESCRIPTION - CYLINDER HEAD........30
DESCRIPTION - VALVE GUIDES..........30
DESCRIPTION........................30
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - HYDRAULIC
LASH ADJUSTER.....................30
DIAGNOSIS AND TESTING - CYLINDER
HEAD GASKET.......................30
REMOVAL.............................31
CLEANING............................31
INSPECTION..........................32
INSTALLATION.........................32
CAMSHAFT(S)
DESCRIPTION.........................33
REMOVAL.............................33
INSTALLATION.........................33
CYLINDER HEAD COVER(S)
REMOVAL.............................34
INSTALLATION.........................34
INTAKE/EXHAUST VALVES & SEATS
STANDARD PROCEDURE - REFACING......34
REMOVAL.............................35
INSTALLATION.........................36
ROCKER ARM
DESCRIPTION.........................37
REMOVAL.............................37
INSTALLATION.........................37
VALVE GUIDE SEALS
DESCRIPTION.........................38
VALVE SPRINGS
DESCRIPTION.........................38
REMOVAL.............................38
INSTALLATION.........................38
KJENGINE - 3.7L 9 - 1

ENGINE BLOCK
DESCRIPTION.........................39
STANDARD PROCEDURE - CYLINDER BORE
HONING............................39
CLEANING............................39
INSPECTION..........................40
CONNECTING ROD BEARINGS
STANDARD PROCEDURE - CONNECTING
ROD BEARING - FITTING...............40
CRANKSHAFT
DESCRIPTION.........................42
REMOVAL.............................43
INSPECTION..........................43
INSTALLATION.........................43
CRANKSHAFT MAIN BEARINGS
STANDARD PROCEDURE
MAIN BEARING - FITTING...............45
CRANKSHAFT OIL SEAL - FRONT
REMOVAL.............................46
INSTALLATION.........................47
CRANKSHAFT OIL SEAL - REAR
REMOVAL.............................48
INSTALLATION.........................48
FLEX PLATE
REMOVAL.............................49
INSTALLATION.........................49
PISTON & CONNECTING ROD
DESCRIPTION.........................49
STANDARD PROCEDURE
CONNECTING ROD BEARING - FITTING . . . 49
STANDARD PROCEDURE - PISTON
FITTING.............................50
REMOVAL.............................50
CLEANING............................51
INSPECTION..........................51
INSTALLATION.........................51
PISTON RINGS
STANDARD PROCEDURE - PISTON RING
FITTING.............................52
VIBRATION DAMPER
REMOVAL.............................54
INSTALLATION.........................55
STRUCTURAL COVER
DESCRIPTION.........................55
OPERATION...........................55
REMOVAL.............................55
INSTALLATION.........................55
FRONT MOUNT
REMOVAL.............................56
INSTALLATION.........................57
REAR MOUNT
REMOVAL.............................57
INSTALLATION.........................57
LUBRICATION
DESCRIPTION.........................57
OPERATION...........................58DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE OIL
LEAK...............................60
DIAGNOSIS AND TESTING - ENGINE OIL
PRESSURE..........................60
DIAGNOSIS AND TESTING - REAR SEAL
AREA LEAKS.........................61
OIL
STANDARD PROCEDURE - ENGINE OIL.....61
OIL FILTER
REMOVAL.............................63
INSTALLATION.........................63
OIL PAN
DESCRIPTION.........................63
REMOVAL.............................63
CLEANING............................63
INSPECTION..........................63
INSTALLATION.........................64
OIL PRESSURE SENSOR/SWITCH
DESCRIPTION.........................65
OPERATION...........................65
REMOVAL.............................65
INSTALLATION.........................65
OIL PUMP
REMOVAL.............................65
DISASSEMBLY.........................65
INSPECTION..........................66
ASSEMBLY............................67
INSTALLATION.........................67
INTAKE MANIFOLD
DESCRIPTION.........................68
DIAGNOSIS AND TESTING - INTAKE
MANIFOLD LEAKS.....................68
REMOVAL.............................68
INSTALLATION.........................69
EXHAUST MANIFOLD
DESCRIPTION.........................69
REMOVAL.............................69
INSTALLATION.........................70
VALVE TIMING
DESCRIPTION.........................71
OPERATION...........................71
STANDARD PROCEDURE
MEASURING TIMING CHAIN WEAR.......71
SERVICE PROCEDURES...............72
BALANCE SHAFT
REMOVAL.............................74
INSTALLATION.........................74
TIMING BELT / CHAIN COVER(S)
REMOVAL.............................74
INSTALLATION.........................76
IDLER SHAFT
REMOVAL.............................77
INSTALLATION.........................77
TIMING BELT/CHAIN AND SPROCKET(S
REMOVAL.............................77
INSPECTION..........................79
INSTALLATION.........................80
9 - 2 ENGINE - 3.7LKJ

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)