2002 JEEP LIBERTY torque

A ªtap downº feature is used to decelerate without
disengaging the speed control system. To decelerate
from an existing recorded target speed, momentarily
depress the COAST switch. For each switch activa-
tion, speed will be lowered approximately 1 mph.
OVERSHOOT/UNDERSHOOT
If the vehicle operator repeatedly presses and
releases the SET button with their foot off of the
accelerator (referred to as a ªlift foot setº), the vehicle
may accelerate and exceed the desired set speed by
up to 5 mph (8 km/h). It may also decelerate to less
than the desired set speed, before finally achieving
the desired set speed.
The Speed Control System has an adaptive strat-
egy that compensates for vehicle-to-vehicle variations
in speed control cable lengths. When the speed con-
trol is set with the vehicle operators foot off of the
accelerator pedal, the speed control thinks there is
excessive speed control cable slack and adapts
accordingly. If the ªlift foot setsº are continually used,
a speed control overshoot/undershoot condition will
develop.
To ªunlearnº the overshoot/undershoot condition,
the vehicle operator has to press and release the set
button while maintaining the desired set speed using
the accelerator pedal (not decelerating or accelerat-
ing), and then turning the cruise control switch to
the OFF position (or press the CANCEL button if
equipped) after waiting 10 seconds. This procedure
must be performed approximately 10±15 times to
completely unlearn the overshoot/undershoot condi-
tion.
DIAGNOSIS AND TESTING - ROAD TEST
Perform a vehicle road test to verify reports of
speed control system malfunction. The road testshould include attention to the speedometer. Speed-
ometer operation should be smooth and without flut-
ter at all speeds.
Flutter in the speedometer indicates a problem
which might cause surging in the speed control sys-
tem. The cause of any speedometer problems should
be corrected before proceeding. Refer to Group 8J,
Instrument Cluster for speedometer diagnosis.
If a road test verifies a system problem and the
speedometer operates properly, check for:
²A Diagnostic Trouble Code (DTC). If a DTC
exists, conduct tests per the Powertrain Diagnostic
Procedures service manual.
²A misadjusted brake (stop) lamp switch. This
could also cause an intermittent problem.
²Loose, damaged or corroded electrical connec-
tions at the servo. Corrosion should be removed from
electrical terminals and a light coating of Mopar
MultiPurpose Grease, or equivalent, applied.
²Leaking vacuum reservoir.
²Loose or leaking vacuum hoses or connections.
²Defective one-way vacuum check valve.
²Secure attachment of both ends of the speed con-
trol servo cable.
²Smooth operation of throttle linkage and throttle
body air valve.
²Failed speed control servo. Do the servo vacuum
test.
CAUTION: When test probing for voltage or conti-
nuity at electrical connectors, care must be taken
not to damage connector, terminals or seals. If
these components are damaged, intermittent or
complete system failure may occur.
SPECIFICATIONS
TORQUE - SPEED CONTROL
DESCRIPTION N-m Ft. Lbs. In. Lbs.
Servo Mounting Bracket-to-Servo Nuts 9 - 75
Servo Mounting Bracket-to-Body Bolts 12 - 105
Speed Control Switch Mounting Screws 1.5 - 14
Vacuum Reservoir Mounting Screws 3 - 20
8P - 2 SPEED CONTROLKJ
SPEED CONTROL (Continued)

mounting bracket displayed in (Fig. 6) is a typical
bracket and may/may not be applicable to this model
vehicle.
(9) Remove servo from mounting bracket. While
removing, note orientation of servo to bracket.INSTALLATION
(1) Position servo to mounting bracket.
(2) Align hole in cable connector with hole in servo
pin. Install cable-to-servo retaining clip.
(3) Insert servo mounting studs through holes in
servo mounting bracket.
(4) Install servo-to-mounting bracket nuts and
tighten. Refer to torque specifications.
(5) Install servo mounting bracket-to-body nuts
and tighten. Refer to torque specifications.
(6) Connect vacuum line at servo.
(7) Connect electrical connector at servo.
(8) Connect servo cable to throttle body. Refer to
servo Cable Removal/Installation.
(9) Install coolant bottle.
(10) Connect negative battery cable to battery.
(11) Before starting engine, operate accelerator
pedal to check for any binding.
SWITCH
DESCRIPTION
There are two separate switch pods that operate
the speed control system. The steering-wheel-
mounted switches use multiplexed circuits to provide
inputs to the PCM for ON, OFF, RESUME, ACCEL-
ERATE, SET, DECEL and CANCEL modes. Refer to
the owner's manual for more information on speed
control switch functions and setting procedures.
The individual switches cannot be repaired. If one
switch fails, the entire switch module must be
replaced.
OPERATION
When speed control is selected by depressing the
ON, OFF switch, the PCM allows a set speed to be
stored in its RAM for speed control. To store a set
speed, depress the SET switch while the vehicle is
moving at a speed between approximately 35 and 85
mph. In order for the speed control to engage, the
brakes cannot be applied, nor can the gear selector
be indicating the transmission is in Park or Neutral.
The speed control can be disengaged manually by:
²Stepping on the brake pedal
²Depressing the OFF switch
²Depressing the CANCEL switch.
The speed control can be disengaged also by any of
the following conditions:
²An indication of Park or Neutral
²The VSS signal increases at a rate of 10 mph
per second (indicates that the co-efficient of friction
between the road surface and tires is extremely low)
²Depressing the clutch pedal.
²Excessive engine rpm (indicates that the trans-
mission may be in a low gear)
Fig. 5 SPEED CONTROL SERVO
1-9T9FITTING
2 - VACUUM LINE
3 - SERVO BRACKET MOUNTING NUTS
4 - SERVO MOUNTING BRACKET
5 - SERVO
6 - SERVO ELECTRICAL CONNECTOR
Fig. 6 SERVO CABLE CLIP REMOVE/INSTALL
TYPICAL
1 - SERVO MOUNTING NUTS (2)
2 - SERVO
3 - CABLE RETAINING CLIP
4 - SERVO CABLE AND SLEEVE
KJSPEED CONTROL 8P - 5
SERVO (Continued)

²The VSS signal decreases at a rate of 10 mph
per second (indicates that the vehicle may have
decelerated at an extremely high rate)
²If the actual speed is not within 20 mph of the
set speed
The previous disengagement conditions are pro-
grammed for added safety.
Once the speed control has been disengaged,
depressing the ACCEL switch restores the vehicle to
the target speed that was stored in the PCM's RAM.
NOTE: Depressing the OFF switch will erase the set
speed stored in the PCM's RAM.
If, while the speed control is engaged, the driver
wishes to increase vehicle speed, the PCM is pro-
grammed for an acceleration feature. With the
ACCEL switch held closed, the vehicle accelerates
slowly to the desired speed. The new target speed is
stored in the PCM's RAM when the ACCEL switch is
released. The PCM also has a9tap-up9feature in
which vehicle speed increases at a rate of approxi-
mately 2 mph for each momentary switch activation
of the ACCEL switch.
The PCM also provides a means to decelerate with-
out disengaging speed control. To decelerate from an
existing recorded target speed, depress and hold the
COAST switch until the desired speed is reached.
Then release the switch. The ON, OFF switch oper-
ates two components: the PCM's ON, OFF input, and
the battery voltage to the brake switch, which powers
the speed control servo.
Multiplexing
The PCM sends out 5 volts through a fixed resistor
and monitors the voltage change between the fixed
resistor and the switches. If none of the switches are
depressed, the PCM will measure 5 volts at the sen-
sor point (open circuit). If a switch with no resistor is
closed, the PCM will measure 0 volts (grounded cir-
cuit). Now, if a resistor is added to a switch, then the
PCM will measure some voltage proportional to the
size of the resistor. By adding a different resistor to
each switch, the PCM will see a different voltage
depending on which switch is pushed.
Another resistor has been added to the 'at rest cir-
cuit' causing the PCM to never see 5 volts. This was
done for diagnostic purposes. If the switch circuit
should open (bad connection), then the PCM will see
the 5 volts and know the circuit is bad. The PCM will
then set an open circuit fault.
REMOVAL
WARNING: BEFORE ATTEMPTING TO DIAGNOSE,
REMOVE OR INSTALL ANY AIRBAG SYSTEM OR
RELATED STEERING WHEEL AND STEERING COL-
UMN COMPONENTS YOU MUST FIRST DISCON-
NECT AND ISOLATE THE NEGATIVE (GROUND)
BATTERY CABLE. WAIT 2 MINUTES FOR SYSTEM
CAPACITOR TO DISCHARGE BEFORE FURTHER
SYSTEM SERVICE. FAILURE TO DO SO COULD
RESULT IN ACCIDENTAL DEPLOYMENT AND POS-
SIBLE PERSONAL INJURY.
(1) Disconnect and isolate negative battery cable
from battery.
(2) Remove airbag module. Refer to Restraint Sys-
tems.
(3) Unplug electrical connector (Fig. 7).
(4) Remove speed control switch mounting screw
(Fig. 7) and remove switch from steering wheel.
INSTALLATION
(1) Position switch to steering wheel.
(2) Install switch mounting screw and tighten.
Refer to torque specifications.
(3) Plug electrical connector into switch.
(4) Install airbag module. Refer to Restraint Sys-
tems.
(5) Connect negative battery cable to battery.
Fig. 7 SPEED CONTROL SWITCH
1 - SWITCH
2 - SCREW
3 - ELECTRICAL CONNECTOR
8P - 6 SPEED CONTROLKJ
SWITCH (Continued)

INSTALLATION
The vacuum reservoir is located behind, and at the
outer end of the instrument panel. To gain access for
testing or removal, remove glovebox assembly. Also
remove fuse box access cover panel at end of instru-
ment panel. On vehicles equipped with LHD (Left
Hand Drive), this fuse access panel is located at right
end of instrument panel. On vehicles equipped with
RHD (Right Hand Drive), this access panel is located
at left end of instrument panel.
(1) Position reservoir to instrument panel.
(2) Install 3 mounting screws and tighten. Refer to
torque specifications.
(3) Connect vacuum line to reservoir fitting.
(4) Install glovebox assembly.
(5) Install fuse box access cover panel.
Fig. 9 VACUUM RESERVOIR REMOVE/INSTALL
1 - VACUUM RESERVOIR
2 - HORIZONTAL MOUNTING SCREWS (2)
3 - VERTICAL MOUNTING SCREW (1)
8P - 8 SPEED CONTROLKJ
VACUUM RESERVOIR (Continued)

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

TRANSMISSION CONTROL MODULE (3.7L) - BLACK 60 WAY
CAV CIRCUIT FUNCTION
1 T1 18LG/BK TRS T1 SENSE
2 T4 18PK/OR TRS T2 SENSE
3 T3 18VT TRS T3 SENSE
4- -
5- -
6 K24 18GY/BK CRANKSHAFT POSITION SENSOR SIGNAL
7 D21 18PK SCI TRANSMIT
8 F45 18YL/BR FUSED IGNITION SWITCH OUTPUT (START)
9 T9 18OR/BK OVERDRIVE PRESSURE SWITCH SENSE
10 T10 18YL/DG TORQUE MANAGEMENT REQUEST SENSE
11 F1 18DB FUSED IGNITION SWITCH OUTPUT (RUN-START)
12 K22 18OR/DB THROTTLE POSITION SENSOR SIGNAL
13 T13 18DB/BK SPEED SENSOR GROUND
14 T14 18LG/WT OUTPUT SPEED SENSOR SIGNAL
15 K30 18PK TRANSMISSION CONTROL RELAY CONTROL
16 T16 14RD TRANSMISSION CONTROL RELAY OUTPUT
17 T16 14RD TRANSMISSION CONTROL RELAY OUTPUT
18 T591 18YL/DB PRESSURE CONTROL SOLENOID CONTROL
19 T119 18WT/DB 2C SOLENOID CONTROL
20 T20 18LB LOW/REVERSE SOLENOID CONTROL
21 - -
22 - -
23 - -
24 - -
25 - -
26 - -
27 - -
28 - -
29 T29 18GY UNDERDRIVE PRESSURE SWITCH SENSE
30 T38 18VT/TN LINE PRESSURE SENSOR SIGNAL
31 - -
32 - -
33 - -
34 - -
35 - -
36 T16 14RD TRANSMISSION CONTROL RELAY OUTPUT
37 Z113 14BK/YL GROUND
38 T39 18GY/LB 5 VOLT SUPPLY
39 Z113 14BK/YL GROUND
40 T140 18VT/LG MS SOLENOID CONTROL
41 T411 18WT/PK TRS T41 SENSE
42 T42 18VT/WT TRS T42 SENSE
43 D25 18VT/YL PCI BUS
44 - -
45 - -
46 D20 18LG SCI RECEIVE
47 T147 18LB 2C PRESSURE SWITCH SENSE
48 T48 18DB 4C PRESSURE SWITCH SENSE
49 T6 18OR/WT OVERDRIVE OFF SWITCH SENSE
50 T50 18DG LOW/REVERSE PRESSURE SWITCH SENSE
51 K4 18BK/LB SENSOR GROUND
52 T52 18RD/BK INPUT SPEED SENSOR SIGNAL
53 Z112 14BK GROUND
8Wa - 80 - 98 8W-80 CONNECTOR PIN-OUTSKJ

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

DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - MECHANICAL
CONDITION POSSIBLE CAUSES CORRECTIONS
NOISY VALVES 1. High or low oil level in
crankcase.1. (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
SPECIFICATIONS).
2. Thin or diluted oil. 2. Change oil and filter.
3. Low oil pressure. 3. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
4. Dirt in lash adjusters. 4. Clean or replace as necessary.
5. Worn rocker arms. 5. Replace as necessary.
7. Worn valve guides. 7. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE).
8. Excessive runout of valve seats
on valve faces.8. Service valves and valve seats.
(Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE).
ENGINE VIBRATION 1. Counter Balance Shaft not timed
properly1. Refer to Engine Timing in this
section
CONNECTING ROD NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
SPECIFICATIONS).
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Connecting rod journal
out-of-round.5. Service or replace crankshaft.
6. Misaligned connecting rods. 6. Replace bent connecting rods.
MAIN BEARING NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
SPECIFICATIONS).
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Excessive end play. 5. Check thrust washers for wear.
6. Crankshaft journal out-of round. 6. Service or replace crankshaft.
7. Loose flywheel or torque
converter.7. Tighten to correct torque
9 - 6 ENGINE - 3.7LKJ
ENGINE - 3.7L (Continued)