engine systems JEEP LIBERTY 2002 KJ / 1.G Owner's Manual

WASHER RESERVOIR
DESCRIPTION
A single washer fluid reservoir is used for both the
front and rear washer systems (Fig. 22). The molded
plastic washer fluid reservoir is mounted on the out-
board side of the right front frame rail in front of the
right front wheel, where it is concealed by the right
front wheel house splash shield. The only visible
component of the washer reservoir is the filler neck
and cap unit, which extends through a hole in the
right front wheel house extension panel into the
engine compartment. A bright yellow plastic filler cap
with an integral bail strap and filler neck mounting
bracket is labeled with an International Control and
Display Symbol icon for ªWindshield Washerº and the
text ªWasher Fluid Onlyº molded into it. The cap
snaps over the open end of the filler neck.
There is a dedicated hole on the outboard side of
the reservoir provided for the mounting of the
washer pump/motor unit, and another dedicated hole
on the rear of the reservoir for the washer fluid level
switch. A snap post receptacle molded into the reser-
voir allows for mounting of the washer pump without
the use of fasteners. The reservoir also features inte-
gral hose routing troughs on its outboard side and
integral routing clips along its top. The washer res-
ervoir is secured to the outboard side of the right
front frame rail by two screws and an integral
molded tab that engages in a slot in the right front
frame rail. Another screw secures the reservoir fillerneck to the upper radiator crossmember in the front
of the engine compartment. The right front fender
wheel house splash shield must be removed to access
the washer reservoir for service.
OPERATION
The washer fluid reservoir provides a secure,
on-vehicle storage location for a large reserve of
washer fluid for operation of the front and rear
washer systems. The washer reservoir filler neck pro-
vides a clearly marked and readily accessible point
from which to add washer fluid to the reservoir. The
washer/pump motor unit is located in a sump area
near the front of the reservoir to be certain that
washer fluid will be available to the pump as the
fluid level in the reservoir becomes depleted. The
washer pump/motor unit is mounted in the lowest
position in the sump. The washer fluid level switch is
mounted just above the sump area of the reservoir so
that there will be adequate warning to the vehicle
operator that the washer fluid level is low, before the
washer system will no longer operate.
REMOVAL
(1) Turn the front wheels full lock to the right.
(2) Unlatch and open the hood.
(3) Disconnect and isolate the battery negative
cable.
(4) Remove the air cleaner housing from the top of
the right front fender wheel house. (Refer to 9 -
ENGINE/AIR INTAKE SYSTEM/AIR CLEANER
ELEMENT - REMOVAL).
(5) Remove the screw that secures the washer res-
ervoir filler neck support to upper radiator cross-
member (Fig. 23).
Fig. 22 Washer Reservoir
1 - CAP
2 - RESERVOIR
3- SNAP POST RECEPTACLE
4 - FRONT HOSE TROUGH
5 - WASHER PUMP HOLE
6 - REAR HOSE TROUGH
7 - HOOK
Fig. 23 Washer Reservoir Cap Remove/Install
1 - SCREW (1)
2 - CAP
3 - UPPER RADIATOR CROSSMEMBER
KJFRONT WIPERS/WASHERS 8R - 21

REAR WIPERS/WASHERS
TABLE OF CONTENTS
page page
REAR WIPERS/WASHERS
DESCRIPTION.........................27
OPERATION...........................29
DIAGNOSIS AND TESTING - REAR WIPER &
WASHER SYSTEM....................30
CLEANING - REAR WIPER & WASHER
SYSTEM............................32
INSPECTION - REAR WIPER & WASHER
SYSTEM............................33
REAR CHECK VALVE
DESCRIPTION.........................34
OPERATION...........................34
REMOVAL.............................34
INSTALLATION.........................35
REAR WASHER HOSES/TUBES
DESCRIPTION.........................35
OPERATION...........................36
REAR WASHER NOZZLE
DESCRIPTION.........................36
OPERATION...........................36
REMOVAL.............................36
INSTALLATION.........................37REAR WIPER ARM
DESCRIPTION.........................37
OPERATION...........................38
REMOVAL.............................38
INSTALLATION.........................38
REAR WIPER BLADE
DESCRIPTION.........................39
OPERATION...........................39
REMOVAL.............................40
INSTALLATION.........................40
REAR WIPER MOTOR
DESCRIPTION.........................41
OPERATION...........................41
REMOVAL.............................42
INSTALLATION.........................42
REAR WIPER/WASHER SWITCH
DESCRIPTION.........................43
OPERATION...........................43
WIPER ARM PARK RAMP
REMOVAL.............................43
INSTALLATION.........................43
REAR WIPERS/WASHERS
DESCRIPTION
An electrically operated fixed interval intermittent
rear wiper and washer system is standard factory-in-
stalled equipment on this model (Fig. 1). The rear
wiper and washer system includes the following
major components, which are described in further
detail elsewhere in this service information:
²Multi-Function Switch- The multi-function
switch is located on the top of the steering column,
just below the steering wheel. The multi-function
switch includes a left (lighting) control stalk and a
right (wiper) control stalk. The right control stalk is
dedicated to providing all of the driver controls for
both the front and rear wiper systems. (Refer to 8 -
ELECTRICAL/LAMPS/LIGHTING - EXTERIOR/
MULTI-FUNCTION SWITCH - DESCRIPTION).
²Rear Check Valve- The rear washer system
check valve is located in the washer plumbing
between the rear roof header and the roof outer
panel near the rear washer nozzle.
²Rear Washer Nozzle- The rear washer nozzle
is secured by a snap fit into a mounting hole in the
roof outer panel above the rear flip-up glass opening.²Rear Washer Plumbing- The plumbing for
the rear washer system consists of rubber hoses and
molded plastic fittings. The plumbing is routed along
the right side of the engine compartment from the
washer reservoir, through the dash into the passen-
ger compartment, up the right cowl side and A-pillar
to the headliner, and above the headliner to the rear
washer nozzle fitting within the rear roof header.
²Rear Wiper Arm- The single rear wiper arm is
secured by a nut directly to the rear wiper motor out-
put shaft, which extends through the center of the
tailgate outer panel near the base of the rear flip-up
glass.
²Rear Wiper Arm Park Ramp- The molded
rubber rear wiper arm park ramp is secured with a
screw to the tailgate outer panel to the right of the
rear wiper motor output shaft bezel. When the rear
wiper system is not in operation, the rear wiper arm
is parked off of the rear flip-up glass on this ramp so
that it will not interfere with or be damaged by the
flip-up glass operation.
²Rear Wiper Blade- The single rear wiper
blade is secured to the rear wiper arm with an inte-
gral latch, and is parked off of the rear flip-up glass
when the rear wiper system is not in operation.
KJREAR WIPERS/WASHERS 8R - 27

²Rear Wiper Module- The rear wiper motor
output shaft is the only visible component of the rear
wiper module. The remainder of the module is con-
cealed within the tailgate below the rear flip-up glass
opening. The rear wiper module includes the module
bracket, the rear wiper motor, and the rear wiper
electronic control circuitry.
²Washer Pump/Motor- The reversible electric
washer pump/motor unit is located in a dedicated
hole on the lower outboard side of the washer reser-
voir, behind the right front wheel house splash
shield. This single reversible washer pump/motor
provides washer fluid to either the front or rear
washer system plumbing, depending upon the direc-
tion of the pump motor rotation. (Refer to 8 - ELEC-
TRICAL/FRONT WIPERS/WASHERS/WASHER
PUMP MOTOR - DESCRIPTION).
²Washer Reservoir- The washer reservoir is
concealed behind the right front wheel house splash
shield ahead of the right front wheel. The washer
reservoir filler neck is the only visible portion of the
reservoir, and it is accessed from the right front cor-
ner of the engine compartment. This single washer
reservoir is shared by both the front and rear washer
systems. (Refer to 8 - ELECTRICAL/FRONT WIP-
ERS/WASHERS/WASHER RESERVOIR - DESCRIP-
TION).
Hard wired circuitry connects the rear wiper and
washer system components to the electrical system of
the vehicle. These hard wired circuits are integral to
several wire harnesses, which are routed throughout
the vehicle and retained by many different methods.
These circuits may be connected to each other, to the
vehicle electrical system and to the rear wiper and
washer system components through the use of a com-
bination of soldered splices, splice block connectors,
and many different types of wire harness terminal
connectors and insulators. Refer to the appropriate
wiring information. The wiring information includes
wiring diagrams, proper wire and connector repair
procedures, further details on wire harness routing
and retention, as well as pin-out and location views
for the various wire harness connectors, splices and
grounds.
OPERATING MODES The components of the rear
wiper and washer system are designed to work in
concert to provide the following operating modes:
²Continuous Wipe Mode- The control ring on
the right (wiper) control stalk of the multi-function
switch has an On position. When selected, this
switch position will cause the rear wiper motor to
operate in a continuous manner at a fixed wipe cycle
speed.
²Intermittent Wipe Mode- The control ring on
the right (wiper) control stalk of the multi-function
switch has a Delay position. When selected, thisswitch position will cause the rear wiper motor to
operate in an intermittent manner at a fixed interval
wipe cycle speed.
²Washer Mode- The control ring on the right
(wiper) control stalk of the multi-function switch has
two momentary Wash positions, one at the end of
each direction of control ring rotation. When the con-
trol ring is rotated to the downward (counterclock-
wise) Wash position, the rear washer system will
dispense washer fluid onto the flip-up glass and the
rear wiper motor will operate in a continuous mode
for as long as the switch is held closed, then provide
several additional wipe cycles after the washer
switch is released (wipe-after-wash mode). When the
control ring is rotated to the upward (clockwise)
Wash position, the rear washer system will dispense
washer fluid onto the flip-up glass and the rear wiper
motor will operate in a continuous mode for as long
as the switch is held closed, then return to fixed wipe
mode operation after the washer switch is released.
²Wipe-After-Wash Mode- The control ring on
the right (wiper) control stalk of the multi-function
switch has two momentary Wash positions, one at
the end of each direction of control ring rotation.
When the control ring is rotated to the downward
(counterclockwise) Wash position, the rear washer
system will dispense washer fluid onto the flip-up
glass and the rear wiper motor will operate in a con-
tinuous mode for as long as the switch is held closed,
then provide several additional wipe cycles after the
washer switch is released.
OPERATION
The rear wiper and washer system is designed to
provide the vehicle operator with a convenient, safe,
and reliable means of maintaining visibility through
the rear flip-up glass. The various components of this
system are designed to convert electrical energy pro-
duced by the vehicle electrical system into the
mechanical action of the wiper blade to wipe the out-
side surface of the glass, as well as into the hydraulic
action of the washer system to apply washer fluid
stored in an on-board reservoir to the area of the
glass to be wiped. When combined, these components
provide the means to effectively maintain clear visi-
bility for the vehicle operator by removing excess
accumulations of rain, snow, bugs, mud, or other
minor debris from the swing gate flip up glass sur-
face that might be encountered while driving the
vehicle under numerous types of inclement operating
conditions.
The vehicle operator initiates all rear wiper and
washer system functions with the right (wiper) con-
trol stalk of the multi-function switch that extends
from the right side of the steering column, just below
the steering wheel. Rotating the control ring on the
KJREAR WIPERS/WASHERS 8R - 29
REAR WIPERS/WASHERS (Continued)

CIRCUIT FUNCTION
U OPEN
V SPEED CONTROL, WIPER/
WASHER
W OPEN
X AUDIO SYSTEMS
Y OPEN
Z GROUNDS
DESCRIPTION - SECTION IDENTIFICATION AND
INFORMATION
The wiring diagrams are grouped into individual
sections. If a component is most likely found in a par-
ticular group, it will be shown complete (all wires,
connectors, and pins) within that group. For exam-
ple, the Auto Shutdown Relay is most likely to be
found in Group 30, so it is shown there complete. It
can, however, be shown partially in another group if
it contains some associated wiring.
Splice diagrams in Section 8W-70 show the entire
splice and provide references to other sections the
splices serves. Section 8W-70 only contains splice dia-
grams that are not shown in their entirety some-
where else in the wiring diagrams.
Section 8W-80 shows each connector and the cir-
cuits involved with that connector. The connectors
are identified using the name/number on the dia-
gram pages.
WIRING SECTION CHART
GROUP TOPIC
8Wa-01 thru
8W-09General information and Diagram
Overview
8Wa-10 thru
8W-19Main Sources of Power and
Vehicle Grounding
8Wa-20 thru
8W-29Starting and Charging
8Wa-30 thru
8W-39Powertrain/Drivetrain Systems
8Wa-40 thru
8W-49Body Electrical items and A/C
8Wa-50 thru
8W-59Exterior Lighting, Wipers and
Trailer Tow
8Wa-60 thru
8W-69Power Accessories
8Wa-70 Splice Information
8Wa-80 Connector Pin Outs
8Wa-91 Connector, Ground and Splice
Locations
DESCRIPTION - CONNECTOR, GROUND AND
SPLICE INFORMATION
CAUTION: Not all connectors are serviced. Some
connectors are serviced only with a harness. A typ-
ical example might be the Supplemental Restraint
System connectors. Always check parts availability
before attempting a repair.
IDENTIFICATION
In-line connectors are identified by a number, as
follows:
²In-line connectors located in the engine compart-
ment are C100 series numbers
²In-line connectors located in the Instrument
Panel area are C200 series numbers.
²In-line connectors located in the body are C300
series numbers.
²Jumper harness connectors are C400 series
numbers.
²Grounds and ground connectors are identified
with a ªGº and follow the same series numbering as
the in-line connectors.
²Splices are identified with an ªSº and follow the
same series numbering as the in-line connectors.
²Component connectors are identified by the com-
ponent name instead of a number. Multiple connec-
tors on a component use a C1, C2, etc. identifier.
LOCATIONS
Section 8W-91 contains connector/ground/splice
location illustrations. The illustrations contain the
connector name (or number)/ground number/splice
number and component identification. Connector/
ground/splice location charts in section 8W-91 refer-
ence the figure numbers of the illustrations.
The abbreviation T/O is used in the component
location section to indicate a point in which the wir-
ing harness branches out to a component. The abbre-
viation N/S means Not Shown in the illustrations
WARNINGS - GENERAL
WARNINGSprovide information to prevent per-
sonal injury and vehicle damage. Below is a list of
general warnings that should be followed any time a
vehicle is being serviced.
WARNING:: ALWAYS WEAR SAFETY GLASSES FOR
EYE PROTECTION.
WARNING: USE SAFETY STANDS ANYTIME A PRO-
CEDURE REQUIRES BEING UNDER A VEHICLE.
8Wa - 01 - 6 8W-01 WIRING DIAGRAM INFORMATIONKJ
WIRING DIAGRAM INFORMATION (Continued)

(1) Position the engine exhaust manifold and gas-
ket on the two studs located on the cylinder head.
Install conical washers and nuts on these studs.
(2) Install remaining conical washers. Starting at
the center arm and working outward, tighten the
bolts and nuts to 25 N´m (18 ft. lbs.) torque.
(3) Install the exhaust heat shields.
(4) Raise and support the vehicle.
CAUTION: Over tightening heat shield fasteners,
may cause shield to distort and/or crack.
(5) Assemble exhaust pipe to manifold and secure
with bolts, nuts and retainers. Tighten the bolts and
nuts to 34 N´m (25 ft. lbs.) torque.
LEFT EXHAUST MANIFOLD
CAUTION: If the studs came out with the nuts when
removing the engine exhaust manifold, install new
studs. Apply sealer on the coarse thread ends.
Water leaks may develop at the studs if this precau-
tion is not taken.
(1) Position the engine exhaust manifold and gas-
ket on the two studs located on the cylinder head.
Install conical washers and nuts on these studs.
(2) Install remaining conical washers. Starting at
the center arm and working outward, tighten the
bolts and nuts to 25 N´m (18 ft. lbs.) torque.
(3) Install the exhaust heat shields.
(4) Raise and support the vehicle.
CAUTION: Over tightening heat shield fasteners,
may cause shield to distort and/or crack.
(5) Assemble exhaust pipe to manifold and secure
with bolts, nuts and retainers. Tighten the bolts and
nuts to 34 N´m (25 ft. lbs.) torque.
VALVE TIMING
DESCRIPTION
The timing drive system has been designed to pro-
vide quiet performance and reliability to support a
non-free wheelingengine. Specifically the intake
valves are non-free wheeling and can be easily dam-
aged with forceful engine rotation if camshaft-to-
crankshaft timing is incorrect. The timing drive
system consists of a primary chain, two secondary
timing chain drives and a counterbalance shaft drive.
OPERATION
The primary timing chain is a single inverted tooth
chain type. The primary chain drives the large 40
tooth idler sprocket directly from a 20 tooth crank-shaft sprocket. Primary chain motion is controlled by
a pivoting leaf spring tensioner arm and a fixed
guide. The arm and the guide both use nylon plastic
wear faces for low friction and long wear. The pri-
mary chain receives oil splash lubrication from the
secondary chain drive and designed oil pump leak-
age. The idler sprocket assembly connects the pri-
mary chain drive, secondary chain drives, and the
counterbalance shaft. The idler sprocket assembly
consists of two integral 26 tooth sprockets a 40 tooth
sprocket and a helical gear that is press-fit to the
assembly. The spline joint for the 40 tooth sprocket is
a non ± serviceable press fit anti rattle type. A spiral
ring is installed on the outboard side of the fifty
tooth sprocket to prevent spline disengagement. The
idler sprocket assembly spins on a stationary idler
shaft. The idler shaft is a light press-fit into the cyl-
inder block. A large washer on the idler shaft bolt
and the rear flange of the idler shaft are used to con-
trol sprocket thrust movement. Pressurized oil is
routed through the center of the idler shaft to pro-
vide lubrication for the two bushings used in the
idler sprocket assembly.
There are two secondary drive chains, both are
roller type, one to drive the camshaft in each SOHC
cylinder head. There are no shaft speed changes in
the secondary chain drive system. Each secondary
chain drives a 26 tooth cam sprocket directly from
the 26 tooth sprocket on the idler sprocket assembly.
A fixed chain guide and a hydraulic oil damped ten-
sioner are used to maintain tension in each second-
ary chain system. The hydraulic tensioners for the
secondary chain systems are fed pressurized oil from
oil reservoir pockets in the block. Each tensioner
incorprates a controled leak path through a device
known as a vent disc located in the nose of the piston
to manage chain loads. Each tensioner also has a
mechanical ratchet system that limits chain slack if
the tensioner piston bleeds down after engine shut
down. The tensioner arms and guides also utilize
nylon wear faces for low friction and long wear. The
secondary timing chains receive lubrication from a
small orifice in the tensioners. This orifice is pro-
tected from clogging by a fine mesh screen which is
located on the back of the hydraulic tensioners.
STANDARD PROCEDURE
MEASURING TIMING CHAIN WEAR
NOTE: This procedure must be performed with the
timing chain cover removed.
(1) Remove the timing chain cover. Refer to Timing
Chain Cover in this section for procedure.
KJENGINE - 3.7L 9 - 71
EXHAUST MANIFOLD (Continued)

CROSS-OVER PIPE
REMOVAL
WARNING: IF TORCHES ARE USED WHEN WORK-
ING ON THE EXHAUST SYSTEM, DO NOT ALLOW
THE FLAME NEAR THE FUEL LINES.
WARNING: THE NORMAL OPERATING TEMPERA-
TURE OF THE EXHAUST SYSTEM IS VERY HIGH.
THEREFORE, NEVER WORK AROUND OR ATTEMPT
TO SERVICE ANY PART OF THE EXHAUST SYSTEM
UNTIL IT IS COOLED. SPECIAL CARE SHOULD BE
TAKEN WHEN WORKING NEAR THE CATALYTIC
CONVERTER. THE TEMPERATURE OF THE CON-
VERTER RISES TO A HIGH LEVEL AFTER A SHORT
PERIOD OF ENGINE OPERATION TIME.
(1) Raise and support the vehicle.
(2) Saturate the bolts and nuts with lubricant.
Allow 5 minutes for penetration.
(3) Remove the retaining fasteners holding cross-
over pipe to exhaust pipe.
(4) Remove the fasteners from the crossover pipe
to the catalytic converter connection.
(5) Remove the crossove pipe from the hanger
insulator (Fig. 3).
INSTALLATION
WARNING: IF TORCHES ARE USED WHEN WORK-
ING ON THE EXHAUST SYSTEM, DO NOT ALLOW
THE FLAME NEAR THE FUEL LINES.
WARNING: THE NORMAL OPERATING TEMPERA-
TURE OF THE EXHAUST SYSTEM IS VERY HIGH.
THEREFORE, NEVER WORK AROUND OR ATTEMPT
TO SERVICE ANY PART OF THE EXHAUST SYSTEM
UNTIL IT IS COOLED. SPECIAL CARE SHOULD BE
TAKEN WHEN WORKING NEAR THE CATALYTIC
CONVERTER. THE TEMPERATURE OF THE CON-
VERTER RISES TO A HIGH LEVEL AFTER A SHORT
PERIOD OF ENGINE OPERATION TIME.
(1) Install the crossove pipe into the hanger insu-
lator.
(2) Install and torque the fasteners in the cross-
over pipe to the left and right catalytic converter con-
nection.
(3) Install and torque the retaining fasteners hold-
ing the crossover pipe to exhaust pipe.
(4) Lower vehicle..
(5) Start engine and check for leaks.
HEAT SHIELDS
DESCRIPTION
Heat shields (Fig. 4) are needed to protect both the
vehicle and the environment from the high tempera-
tures developed by the catalytic converter. The cata-
lytic converter releases additional heat into the
exhaust system. Under severe operating conditions,
the temperature increases in the area of the con-
verter. Such conditions can exist when the engine
misfires or otherwise does not operate at peak effi-
ciency.
MUFFLER
DESCRIPTION
The 2.4L and 3.7L engine uses a galvanized steel
muffler (Fig. 5) to control exhaust noise levels and
exhaust back pressure.
REMOVAL
All original equipment exhaust systems are manu-
factured with the exhaust tailpipe welded to the muf-
fler. Service replacement mufflers and exhaust
tailpipes are either clamped together or welded
together.Fig. 3 Crossover Pipe
1 - Crossover-toCatalytic Converter flange
2 - Crossover Pipe
3 - Crossover Pipe to Tail Pipe Flange
4 - Hanger Bracket
11s - 4 EXHAUST SYSTEMKJ

OPERATION
Fuel is picked up in the fuel tank by the fuel pump
module. This module is located on the bottom of the
fuel tank.
A fuel return system is provided within the fuel
pump module using check valves. A separate fuel
return line from the engine to the tank is not used.
The fuel pressure regulator and the main fuel filter
are not combined. They are separate items.
The fuel tank assembly consists of: the fuel tank,
fuel pump module assembly, fuel pump module lock
ring/gasket, ORVR components. Refer to 25, Emis-
sion Control System for ORVR information.
A fuel filler/vent tube assembly using a pressure/
vacuum, 1/4 turn fuel filler cap is used. The fuel
filler tube contains a flap door located below the fuel
fill cap. A one-way check valve is installed into the
tanks fuel fill fitting.
Also to be considered part of the fuel system is the
evaporation control system and ORVR system. This
is designed to reduce the emission of fuel vapors into
the atmosphere. The description and function of the
Evaporative Control System is found in 25, Emission
Control Systems.
Both fuel filters (mounted to front of fuel tank, and
inside the bottom fuel pump module) are designed for
extended service. They do not require normal sched-
uled maintenance. The bottom section of the fuel
pump module (with included filter) should only be
replaced if a diagnostic procedure indicates to do so.
Also, the fuel filter mounted to the front of the fuel
tank should only be replaced if a diagnostic proce-
dure indicates to do so.
DIAGNOSIS AND TESTING - FUEL PRESSURE
LEAK DOWN TEST
Use this test in conjunction with the Fuel Pump
Pressure Test and Fuel Pump Capacity Test.
Check Valve Operation:The electric fuel pump
outlet contains a one-way check valve to prevent fuel
flow back into the tank and to maintain fuel supply
line pressure (engine warm) when pump is not oper-
ational. It is also used to keep the fuel supply line
full of gasoline when pump is not operational. After
the vehicle has cooled down, fuel pressure may drop
to 0 psi (cold fluid contracts), but liquid gasoline will
remain in fuel supply line between the check valve
and fuel injectors.Fuel pressure that has
dropped to 0 psi on a cooled down vehicle
(engine off) is a normal condition.When the elec-
tric fuel pump is activated, fuel pressure should
immediately(1±2 seconds) rise to specification.
Abnormally long periods of cranking to restart a
hotengine that has been shut down for a short
period of time may be caused by:
²Fuel pressure bleeding past a fuel injector(s).²Fuel pressure bleeding past the check valve in
the fuel pump module.
(1) Disconnect the fuel inlet line at fuel rail. Refer
to Quick Connect Fittings for procedures. On some
engines, air cleaner housing removal may be neces-
sary before fuel line disconnection.
(2) Obtain correct Fuel Line Pressure Test Adapter
Tool Hose. Tool number 6539 is used for 5/16º fuel
lines and tool number 6631 is used for 3/8º fuel lines.
(3) Connect correct Fuel Line Pressure Test
Adapter Tool Hose between disconnected fuel line
and fuel rail (Fig. 2).
(4) Connect the 0-414 kPa (0-60 psi) fuel pressure
test gauge (from Gauge Set 5069) to the test port on
the appropriate Adaptor Tool.The DRBtIII Scan
Tool along with the PEP module, the 500 psi
pressure transducer, and the transducer-to-test
port adapter may also be used in place of the
fuel pressure gauge.
The fittings on both tools must be in good
condition and free from any small leaks before
performing the proceeding test.
(5) Start engine and bring to normal operating
temperature.
(6) Observe test gauge. Normal operating pressure
should be 339 kPa +/±34 kPa (49.2 psi +/±5 psi).
(7) Shut engine off.
Fig. 2 CONNECTING ADAPTER TOOLÐTYPICAL
1 - VEHICLE FUEL LINE
2 - TEST PORT ªTº
3 - SPECIAL TOOL 6923, 6631, 6541 OR 6539
4 - FUEL PRESSURE TEST GAUGE
5 - FUEL LINE CONNECTION AT RAIL
6 - FUEL RAIL
KJFUEL DELIVERY 14 - 3
FUEL DELIVERY (Continued)

ronment that they operate in, that keep them from
being interchangeable.
Maintaining correct sensor temperature at all
times allows the system to enter into closed loop
operation sooner. Also, it allows the system to remain
in closed loop operation during periods of extended
idle.
In Closed Loop operation, the PCM monitors cer-
tain O2 sensor input(s) along with other inputs, and
adjusts the injector pulse width accordingly. During
Open Loop operation, the PCM ignores the O2 sensor
input. The PCM adjusts injector pulse width based
on preprogrammed (fixed) values and inputs from
other sensors.
Upstream Sensor - 2.4L Engine:The upstream
sensor (1/1) provides an input voltage to the PCM.
The input tells the PCM the oxygen content of the
exhaust gas. The PCM uses this information to fine
tune fuel delivery to maintain the correct oxygen con-
tent at the downstream oxygen sensor. The PCM will
change the air/fuel ratio until the upstream sensor
inputs a voltage that the PCM has determined will
make the downstream sensor output (oxygen content)
correct.
The upstream oxygen sensor also provides an input
to determine catalytic convertor efficiency.
Downstream Sensor - 2.4L Engine:The down-
stream oxygen sensor (1/2) is also used to determine
the correct air-fuel ratio. As the oxygen content
changes at the downstream sensor, the PCM calcu-
lates how much air-fuel ratio change is required. The
PCM then looks at the upstream oxygen sensor volt-
age and changes fuel delivery until the upstream
sensor voltage changes enough to correct the down-
stream sensor voltage (oxygen content).
The downstream oxygen sensor also provides an
input to determine catalytic convertor efficiency.
Upstream Sensors - 3.7L Engine:Two upstream
sensors are used (1/1 and 2/1). The 1/1 sensor is the
first sensor to receive exhaust gases from the #1 cyl-
inder. They provide an input voltage to the PCM. The
input tells the PCM the oxygen content of the
exhaust gas. The PCM uses this information to fine
tune fuel delivery to maintain the correct oxygen con-
tent at the downstream oxygen sensors. The PCM
will change the air/fuel ratio until the upstream sen-
sors input a voltage that the PCM has determined
will make the downstream sensors output (oxygen
content) correct.
The upstream oxygen sensors also provide an input
to determine mini-catalyst efficiency. Main catalytic
convertor efficiency is not calculated with this pack-
age.
Downstream Sensors - 3.7L Engine:Two down-
stream sensors are used (1/2 and 2/2). The down-
stream sensors are used to determine the correct air-fuel ratio. As the oxygen content changes at the
downstream sensor, the PCM calculates how much
air-fuel ratio change is required. The PCM then looks
at the upstream oxygen sensor voltage, and changes
fuel delivery until the upstream sensor voltage
changes enough to correct the downstream sensor
voltage (oxygen content).
The downstream oxygen sensors also provide an
input to determine mini-catalyst efficiency. Main cat-
alytic convertor efficiency is not calculated with this
package.
Engines equipped with either a downstream sen-
sor(s), or a post-catalytic sensor, will monitor cata-
lytic convertor efficiency. If efficiency is below
emission standards, the Malfunction Indicator Lamp
(MIL) will be illuminated and a Diagnostic Trouble
Code (DTC) will be set. Refer to Monitored Systems
in Emission Control Systems for additional informa-
tion.
REMOVAL
CAUTION: Never apply any type of grease to the
oxygen sensor electrical connector, or attempt any
soldering of the sensor wiring harness.
Refer to (Fig. 20), (Fig. 21) or (Fig. 22) for O2S
(oxygen sensor) location.
Fig. 20 OXYGEN SENSORS - 2.4L
1 - ELECTRICAL CONNECTORS
2 - UPSTREAM SENSOR (1/1)
3 - ELECTRICAL CONNECTORS
4 - DOWNSTREAM SENSOR (1/2)
KJFUEL INJECTION 14 - 41
OXYGEN SENSOR (Continued)

STEERING
TABLE OF CONTENTS
page page
STEERING
DESCRIPTION..........................1
OPERATION............................1
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - POWER
STEERING SYSTEM....................1DIAGNOSIS AND TESTING - POWER
STEERING FLOW AND PRESSURE........3
COLUMN...............................5
GEAR.................................13
LINKAGE..............................16
PUMP.................................17
STEERING
DESCRIPTION
Power steering systems consist of:
²Steering column & Intermediate Shaft
²Rack and pinion steering gear
²Belt driven hydraulic steering pump
²Pump pressure, supply and return hoses
²Oil Cooler
OPERATION
The steering column intermediate shaft attaches
the steering column to the gear pinion. The rotation
of the pinion moves the gear rack from side-to-side.
This lateral action of the rack pushes and pulls the
tie rods to change the direction of the front wheels.
Power assist is provided by an engine mounted
hydraulic pump. The pump supplies hydraulic fluid
to the steering gear. All vehicles are equipped with
an oil cooler.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - POWER STEERING SYSTEM
STEERING NOISE
There is some noise in all power steering systems. One of the most common is a hissing sound evident at a
standstill/parking, or when the steering is at the end of it's travel. Hiss is a high frequency noise similar to that
of a water tap being closed slowly. The noise is present in all valves that have a high velocity fluid passing through
an orifice. There is no relationship between this noise and steering performance.
CONDITION POSSIBLE CAUSES CORRECTION
OBJECTIONAL HISS OR
WHISTLE1. Steering intermediate shaft to dash panel
seal.1. Check and repair seal at dash
panel.
2. Noisy valve in power steering gear. 2. Replace steering gear.
1. Gear mounting bolts loose. 1. Tighten bolts to specification.
2. Loose or damaged suspension
components.2. Inspect and repair suspension.
3. Internal gear noise. 3. Replace steering gear.
4. Loose or damaged intermediate shaft or
column.4. Inspect and repair or replace.
MOAN Pressure hose in contact with other
components.Reposition hose.
CHIRP OR SQUEAL 1. Loose belt. 1. Adjust or replace.
KJSTEERING 19 - 1

HEATING & AIR CONDITIONING
TABLE OF CONTENTS
page page
HEATING & AIR CONDITIONING
DESCRIPTION
DESCRIPTION - HEATER AND AIR
CONDITIONER........................1
DESCRIPTION - COOLING SYSTEM
REQUIREMENTS.......................1
DESCRIPTION - REFRIGERANT SYSTEM
SERVICE PORT........................2
OPERATION
OPERATION - HEATER AND AIR
CONDITIONER........................2
OPERATION - REFRIGERANT SYSTEM
SERVICE PORT........................2
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - A/C
PERFORMANCE.......................2DIAGNOSIS AND TESTING - HEATER
PERFORMANCE.......................6
DIAGNOSIS AND TESTING - VACUUM
SYSTEM.............................6
STANDARD PROCEDURE - DIODE
REPLACEMENT.......................9
SPECIFICATIONS
A/C APPLICATION TABLE................9
SPECIFICATIONS.....................10
CONTROLS.............................11
DISTRIBUTION..........................29
PLUMBING.............................38
HEATING & AIR
CONDITIONING
DESCRIPTION
DESCRIPTION - HEATER AND AIR
CONDITIONER
All vehicles are equipped with a common HVAC
housing assembly (Fig. 1). The system combines air
conditioning, heating, and ventilating capabilities in
a single unit housing mounted under the instrument
panel. On heater-only systems, the evaporator coil is
omitted from the housing.
DESCRIPTION - COOLING SYSTEM
REQUIREMENTS
To maintain the performance level of the HVAC
system, the engine cooling system must be properly
maintained. The use of a bug screen is not recom-
mended. Any obstructions in front of the radiator or
condenser will reduce the performance of the air con-
ditioning and engine cooling systems.
The engine cooling system includes the heater core
and the heater hoses. Refer to Engine Cooling for
more information before the opening of, or attempt-
ing any service to the engine cooling system.
Fig. 1 Blend Door
1 - DEFROSTER DOOR
2- HEATER CORE
3- BLEND DOORS
4- BLOWER MOTOR HOUSING
5- EVAPORATOR (A/C ONLY)
6- LOWER HVAC CASE ASSEMBLY
KJHEATING & AIR CONDITIONING 24 - 1