check engine JEEP GRAND CHEROKEE 2002 WJ / 2.G Workshop Manual

INSTALLATION
INSTALLATION - 4.0L
The IAC motor is located on the throttle body.
(1) Install IAC motor to throttle body.
(2) Install and tighten two mounting bolts (screws)
to 7 N´m (60 in. lbs.) torque.
(3) Install electrical connector.
(4) Install air cleaner duct/air box to throttle body.
INSTALLATION - 4.7L
(1) Install IAC motor to throttle body.
(2) Install and tighten two mounting bolts (screws)
to 7 N´m (60 in. lbs.) torque.
(3) Install electrical connector.
(4) Install air duct/air box to throttle body.
INTAKE AIR TEMPERATURE
SENSOR
DESCRIPTION
The 2±wire Intake Manifold Air Temperature (IAT)
sensor is installed in the intake manifold with the
sensor element extending into the air stream.
The IAT sensor is a two-wire Negative Thermal
Coefficient (NTC) sensor. Meaning, as intake mani-
fold temperature increases, resistance (voltage) in the
sensor decreases. As temperature decreases, resis-
tance (voltage) in the sensor increases.
OPERATION
The IAT sensor provides an input voltage to the
Powertrain Control Module (PCM) indicating the
density of the air entering the intake manifold based
upon intake manifold temperature. At key-on, a
5±volt power circuit is supplied to the sensor from
the PCM. The sensor is grounded at the PCM
through a low-noise, sensor-return circuit.
The PCM uses this input to calculate the following:
²Injector pulse-width
²Adjustment of spark timing (to help prevent
spark knock with high intake manifold air-charge
temperatures)
The resistance values of the IAT sensor is the same
as for the Engine Coolant Temperature (ECT) sensor.
REMOVAL
REMOVAL - 4.0L
The Intake Manifold Air Temperature (IAT) sensor
is installed into the intake manifold plenum near the
front of the throttle body (Fig. 27).
(1) Disconnect electrical connector from sensor.
(2) Remove sensor from intake manifold.
REMOVAL - 4.7L
The Intake Manifold Air Temperature (IAT) sensor
is located on the left side of the intake manifold.
Threaded Type Sensor
(1) Disconnect electrical connector from sensor.
(2) Remove sensor from intake manifold (Fig. 28).
Snap-In Type Sensor
(1) Disconnect electrical connector from IAT sen-
sor.
(2) Clean dirt from intake manifold at sensor base.
(3) Gently lift on small plastic release tab (Fig. 30)
or (Fig. 29) and rotate sensor about 1/4 turn counter-
clockwise for removal.
(4) Check condition of sensor o-ring.
Fig. 27 Intake Manifold Air Sensor LocationÐ4.0L
Engine
1 - MOUNTING BOLTS (4)
2 - THROTTLE BODY
3 - IAC MOTOR
4 - ELEC. CONN.
5 - TPS
6 - MAP SENSOR
7 - ELEC. CONN.
8 - IAT SENSOR
9 - ELEC. CONN.
14 - 46 FUEL INJECTIONWJ
IDLE AIR CONTROL MOTOR (Continued)

(2) Remove two MAP sensor mounting bolts
(screws) (Fig. 31).
(3) While removing MAP sensor, slide the rubber
L-shaped fitting (Fig. 31) from the throttle body.
(4) Remove rubber L-shaped fitting from MAP sen-
sor.
REMOVAL - 4.7L
The MAP sensor is located on the front of the
intake manifold (Fig. 32). An o-ring seals the sensor
to the intake manifold.
(1) Disconnect electrical connector at sensor.
(2) Clean area around MAP sensor.
(3) Remove 2 sensor mounting bolts (Fig. 32).
(4) Remove MAP sensor from intake manifold.
INSTALLATION
INSTALLATION - 4.0L
The MAP sensor is mounted to the side of the
throttle body (Fig. 40). An L-shaped rubber fitting is
used to connect the MAP sensor to throttle body (Fig.
31).
(1) Install rubber L-shaped fitting to MAP sensor.
(2) Position sensor to throttle body while guiding
rubber fitting over throttle body vacuum nipple.
(3) Install MAP sensor mounting bolts (screws).
Tighten screws to 3 N´m (25 in. lbs.) torque.
(4) Install air cleanerduct/air box.
INSTALLATION - 4.7L
The MAP sensor is located on the front of the
intake manifold (Fig. 32). An o-ring seals the sensor
to the intake manifold.
(1) Clean MAP sensor mounting hole at intake
manifold.
(2) Check MAP sensor o-ring seal for cuts or tears.
(3) Position sensor into manifold.
(4) Install MAP sensor mounting bolts (screws).
Tighten screws to 3 N´m (25 in. lbs.) torque.
(5) Connect electrical connector.
O2S HEATER RELAY
DESCRIPTION
The 2 oxygen (O2) sensor heater relays (upstream
and downstream) are located in the Powertrain Dis-
tribution Center (PDC).
OPERATION
Engines equipped with the California (NAE) Emis-
sions Package usefour O2 sensors.
Two of the four sensor heater elements (upstream
sensors 1/1 and 2/1) are controlled by the upstream
heater relay through output signals from the Power-
train Control Module (PCM).
Fig. 31 Rubber L-Shaped FittingÐMAP Sensor-to-
Throttle BodyÐ4.0L Engine
1 - THROTTLE BODY
2 - MAP SENSOR
3 - RUBBER FITTING
4 - MOUNTING SCREWS (2)Fig. 32 MAP and ECT Sensor LocationsÐ4.7L V±8
Engine
1 - ECT SENSOR
2 - MOUNTING BOLTS (2)
3 - MAP SENSOR
4 - INTAKE MANIFOLD
WJFUEL INJECTION 14 - 49
MAP SENSOR (Continued)

The other two heater elements (downstream sen-
sors 1/2 and 2/2) are controlled by the downstream
heater relay through output signals from the PCM.
To avoid a large simultaneous current surge, power
is delayed to the 2 downstream heater elements by
the PCM for approximately 2 seconds.
REMOVAL
(1) Remove PDC cover.
(2) Remove relay from PDC.
(3) Check condition of relay terminals and PDC
connector terminals for damage or corrosion. Repair
if necessary before installing relay.
(4) Check for pin height (pin height should be the
same for all terminals within the PDC connector).
Repair if necessary before installing relay.
INSTALLATION
(1) Install relay to PDC.
(2) Install cover to PDC.
O2S SENSOR
DESCRIPTION
The Oxygen Sensors (O2S) are attached to, and
protrude into the vehicle exhaust system. Depending
on the emission package, the vehicle may use a total
of either 2 or 4 sensors.
Federal Emissions Package:Two sensors are
used: upstream (referred to as 1/1) and downstream
(referred to as 1/2). With this emission package, the
upstream sensor (1/1) is located just before the main
catalytic convertor. The downstream sensor (1/2) is
located just after the main catalytic convertor.
4.7L V-8 With California Emissions Package:
On this emissions package, 4 sensors are used: 2
upstream (referred to as 1/1 and 2/1) and 2 down-
stream (referred to as 1/2 and 2/2). With this emis-
sion package, the right upstream sensor (2/1) is
located in the right exhaust downpipe just before the
mini-catalytic convertor. The left upstream sensor
(1/1) is located in the left exhaust downpipe just
before the mini-catalytic convertor. The right down-
stream sensor (2/2) is located in the right exhaust
downpipe just after the mini-catalytic convertor, and
before the main catalytic convertor. The left down-
stream sensor (1/2) is located in the left exhaust
downpipe just after the mini-catalytic convertor, and
before the main catalytic convertor.
4.0L 6±Cylinder With California Emissions
Package:On this emissions package, 4 sensors are
used: 2 upstream (referred to as 1/1 and 2/1) and 2
downstream (referred to as 1/2 and 2/2). With this
emission package, the rear/upper upstream sensor
(2/1) is located in the exhaust downpipe just beforethe rear mini-catalytic convertor. The front/upper
upstream sensor (1/1) is located in the exhaust down-
pipe just before the front mini-catalytic convertor.
The rear/lower downstream sensor (2/2) is located in
the exhaust downpipe just after the rear mini-cata-
lytic convertor, and before the main catalytic conver-
tor. The front/lower downstream sensor (1/2) is
located in the exhaust downpipe just after the front
mini-catalytic convertor, and before the main cata-
lytic convertor.
OPERATION
An O2 sensor is a galvanic battery that provides
the PCM with a voltage signal (0-1 volt) inversely
proportional to the amount of oxygen in the exhaust.
In other words, if the oxygen content is low, the volt-
age output is high; if the oxygen content is high the
output voltage is low. The PCM uses this information
to adjust injector pulse-width to achieve the
14.7±to±1 air/fuel ratio necessary for proper engine
operation and to control emissions.
The O2 sensor must have a source of oxygen from
outside of the exhaust stream for comparison. Cur-
rent O2 sensors receive their fresh oxygen (outside
air) supply through the O2 sensor case housing.
Four wires (circuits) are used on each O2 sensor: a
12±volt feed circuit for the sensor heating element; a
ground circuit for the heater element; a low-noise
sensor return circuit to the PCM, and an input cir-
cuit from the sensor back to the PCM to detect sen-
sor operation.
Oxygen Sensor Heaters/Heater Relays:
Depending on the emissions package, the heating ele-
ments within the sensors will be supplied voltage
from either the ASD relay, or 2 separate oxygen sen-
sor relays. Refer to Wiring Diagrams to determine
which relays are used.
The O2 sensor uses a Positive Thermal Co-efficient
(PTC) heater element. As temperature increases,
resistance increases. At ambient temperatures
around 70ÉF, the resistance of the heating element is
approximately 4.5 ohms on 4.0L engines. It is
approximately 13.5 ohms on the 4.7L engine. As the
sensor's temperature increases, resistance in the
heater element increases. This allows the heater to
maintain the optimum operating temperature of
approximately 930É-1100ÉF (500É-600É C). Although
the sensors operate the same, there are physical dif-
ferences, due to the environment 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.
14 - 50 FUEL INJECTIONWJ
O2S HEATER RELAY (Continued)

(7) From inside vehicle, install clip holding cable
to dashpanel (Fig. 16).
(8) From inside vehicle, slide throttle cable core
wire into opening in top of pedal arm.
(9) Push cable retainer (clip) into pedal arm open-
ing until it snaps in place.
(10) Before starting engine, operate accelerator
pedal to check for any binding.
INSTALLATION - 4.7L
(1) Slide accelerator cable plastic mount into
bracket. Continue sliding until tab (Fig. 39) is
aligned to hole in mounting bracket.
(2) Route accelerator cable over top of cable cam.
(3) Connect cable end to throttle body bellcrank
pin (snaps on rearward).
(4) Slide rubber grommet away from plastic cable
housing.
(5) Install rubber grommet into dash panel until
seated.
(6) Push cable housing into rubber grommet and
through opening in dash panel.
(7) From inside vehicle, install clip holding cable
to dashpanel (Fig. 16).
(8) From inside vehicle, slide throttle cable core
wire into opening in top of pedal arm.(9) Push cable retainer (clip) into pedal arm open-
ing until it snaps in place.
(10) Snap cable into plenum routing clip.
(11) Install air box to throttle body.
(12) Before starting engine, operate accelerator
pedal to check for any binding.
THROTTLE POSITION SENSOR
DESCRIPTION
The 3±wire Throttle Position Sensor (TPS) is
mounted on the throttle body and is connected to the
throttle blade.
OPERATION
The TPS is a 3±wire variable resistor that provides
the Powertrain Control Module (PCM) with an input
signal (voltage) that represents the throttle blade
position of the throttle body. The sensor is connected
to the throttle blade shaft. As the position of the
throttle blade changes, the resistance (output volt-
age) of the TPS changes.
The PCM supplies approximately 5 volts to the
TPS. The TPS output voltage (input signal to the
PCM) represents the throttle blade position. The
PCM receives an input signal voltage from the TPS.
This will vary in an approximate range of from .26
volts at minimum throttle opening (idle), to 4.49 volts
at wide open throttle. Along with inputs from other
sensors, the PCM uses the TPS input to determine
current engine operating conditions. In response to
engine operating conditions, the PCM will adjust fuel
injector pulse width and ignition timing.
The PCM needs to identify the actions and position
of the throttle blade at all times. This information is
needed to assist in performing the following calcula-
tions:
²Ignition timing advance
²Fuel injection pulse-width
²Idle (learned value or minimum TPS)
²Off-idle (0.06 volt)
²Wide Open Throttle (WOT) open loop (2.608
volts above learned idle voltage)
²Deceleration fuel lean out
²Fuel cutoff during cranking at WOT (2.608 volts
above learned idle voltage)
²A/C WOT cutoff (certain automatic transmis-
sions only)
Fig. 39 Accelerator Cable Release TabÐ4.7L V-8
Engine
1 - ACCELERATOR CABLE
2 - PLASTIC CABLE MOUNT
3 - PRESS TAB FOR REMOVAL
4 - CABLE BRACKET
5 - SLIDE FOR REMOVAL
14 - 56 FUEL INJECTIONWJ
THROTTLE CONTROL CABLE (Continued)

INSTALLATION
INSTALLATION - 4.0L
The TPS is mounted to the throttle body.
The throttle shaft end of throttle body slides into a
socket in the TPS (Fig. 43). The TPS must be
installed so that it can be rotated a few degrees. (If
sensor will not rotate, install sensor with throttle
shaft on other side of socket tangs). The TPS will be
under slight tension when rotated.
(1) Install TPS and retaining screws.
(2) Tighten screws to 7 N´m (60 in. lbs.) torque.
(3) Connect TPS electrical connector to TPS.
(4) Manually operate throttle (by hand) to check
for any TPS binding before starting engine.
INSTALLATION - 4.7L
The throttle shaft end of throttle body slides into a
socket in TPS (Fig. 44). The TPS must be installed so
that it can be rotated a few degrees. If sensor will
not rotate, install sensor with throttle shaft on other
side of socket tangs. The TPS will be under slight
tension when rotated.
(1) Install TPS and two retaining bolts.
(2) Tighten bolts to 7 N´m (60 in. lbs.) torque.
(3) Manually operate throttle control lever by hand
to check for any binding of TPS.
(4) Connect TPS electrical connector to TPS.
(5) Install air duct/air box to throttle body.
Fig. 43 Throttle Position Sensor InstallationÐ4.0L
Engine
1 - TANGS
2 - THROTTLE SHAFT
3 - THROTTLE BODY
4 - TPS
Fig. 44 TPS InstallationÐ4.7L
1 - THROTTLE BODY
2 - LOCATING TANGS
3 - THROTTLE POSITION SENSOR
4 - SOCKET
5 - THROTTLE SHAFT
14 - 58 FUEL INJECTIONWJ
THROTTLE POSITION SENSOR (Continued)

(8) Start engine and let idle long enough to circu-
late power steering fluid through flow/pressure test
gauge.
(9) Shut off the engine and check the fluid level,
add fluid as necessary. Start engine again and let
idle.
(10) The initial pressure reading should be
345-552 kPa (50-80 psi). If pressure is higher inspect
the hoses for restrictions and repair as necessary.
(11) Increase the engine speed to 1500 RPM and
read the flow meter. The reading should be 2.4 - 2.8
GPM, if the reading is below this specification the
pump should be replaced.
CAUTION: This next step involves testing maximum
pump pressure output and flow control valve oper-
ation. Do not leave valve closed for more than three
seconds as the pump could be damaged.
(12) Close valve fully three times for three seconds
and record highest pressure indicated each time.All
three readings must be at pump relief pressure
specifications and within 345 kPa (50 psi) of
each other.
²Pressures above specifications but not within
345 kPa (50 psi) of each other, replace pump.
²Pressures within 345 kPa (50 psi) of each other
but below specifications, replace pump.
CAUTION: Do not force the pump to operate against
the stops for more than 2 to 4 seconds at a time
because, pump damage will result.
(13) Open the test valve and turn the steering
wheel to the extreme left and right positions against
the stops. Record the highest pressure reading at
each position. Compare readings to the pump specifi-
cations chart. If pressures readings are not within 50
psi. of each other, the gear is leaking internally and
must be repaired.
GEAR INLET SPECIFICATIONS 4.0L & 4.7L
ENGINERELIEF
PRESSURE   50FLOW RATE
(GPM)
4.0L 9653 kPa (1400 psi)
1500 RPM 2.4 - 2.8
GPM
4.7L 9653 kPa (1450 psi)
PUMP MOTOR SPECIFICATIONS 4.7L
ENGINERELIEF
PRESSURE   50FLOW RATE
(GPM)
4.7L 9653 kPa (1900 psi)1100 RPM 2.4-2.8
GPM Minium
@ 200 psi
DIAGNOSIS AND TESTING - 4.7L -
HYDRAULIC
The following procedures are used to test the oper-
ation of the power steering and hydraulic fan sys-
tems on the vehicle. This test will provide the gallons
per minute (GPM) or flow rate of the power steering
pump along with any maximum relief pressure. Per-
form test anytime a power steering system problem
is present. This test will determine if the power
steering pump, hydraulic fan, and power steering
gear are not functioning properly. It will also deter-
mine if the flow coming out of the hydraulic fan
motor is sufficient for the power steering gear. The
following pressure and flow test is performed using
the Power Steering Analyzer Tool kit 6815 (Fig. 2)
and Adapter kit 8630 (Fig. 3).
FLOW TEST - FLOW FROM POWER STEERING
PUMP
(1) Check the power steering belt to ensure it is in
good condition and adjusted properly.
(2) Connect the pressure gauge hose from the
Power Steering Analyzer to Tube 8630-2.
(3) Connect Adapter 8630-3 to Power Steering
Analyzer test valve end.
(4) Disconnect the high pressure hose from the
power steering pump.
(5) Connect Tube 8630-2 to the pump hose fitting.
(6) Connect the power steering hose from the fan
motor to Adapter 8630-3.
(7) Open the test valve completely.
(8) Start engine and let idle long enough to circu-
late power steering fluid through the flow/pressure
test gauge.
(9) Shut off the engine and check the fluid level,
add fluid ass necessary. Start engine again and let
idle.
(10) The initial pressure reading should be 483 -
690 kPa (70 - 100 psi). If pressure is higher inspect
the hoses for restrictions and repair as necessary.
Fig. 3 4.7L HYDRAULIC POWER STEERING TEST
ADAPTERS
WJSTEERING 19 - 5
STEERING (Continued)

(11) Increase the engine speed to 1100 rpm and
read the flow meter. The reading should be 2.6 GPM
minimum, if the reading is below this specification,
the pump should be replaced.
FLOW AND PRESSURE TEST - FLOW FROM
HYDRAULIC FAN MOTOR TO STEERING GEAR
(should be done if necessary after the Pump flow
test)
(1) Connect the pressure gauge hose from the
Power Steering Analyzer to Fitting 8630-1.
(2) Connect Adapter 8630-4 to Power Steering
Analyzer test valve end.
(3) Disconnect the high pressure hose from the
power steering gear.
(4) Connect Fitting 8630-1 to the high pressure
hose.
(5) Connect Adapter 8630-4 to the power steering
gear.
(6) Open the test valve completely.
(7) Start engine and let idle long enough to circu-
late power steering fluid through the flow/pressure
test gauge.
(8) Shut off the engine and check the fluid level,
add fluid ass necessary. Start engine again and let
idle.
(9) The initial pressure reading should be 345-552
kPa (50-80 psi). If pressure is higher inspect the
hoses for restrictions and repair as necessary.(10) Increase the engine speed to 1500 RPM and
read the flow meter. The reading should be 2.4 - 2.8
GPM if the reading is below this specification the fan
should be replaced.
CAUTION: This next step involves testing maximum
fan motor steering relief pressure. Do not leave the
valve closed for more than three seconds.
(11) Close the valve fully three times for three sec-
onds and record highest pressures indicated each
time. All three readings must be at fan motor steer-
ing relief pressures.
(12) Open the test valve and turn the steering
wheel to the extreme left and right positions against
the stops. Record the highest pressure readings at
each position. If pressure readings are not within 50
psi from each other, the gear is leaking internally
and must be repaired.
PUMP MOTOR SPECIFICATIONS 4.7L
ENGINERELIEF
PRESSURE   50FLOW RATE
(GPM)
4.7L 9653 kPa (1900 psi)1100 RPM 2.4-2.8
GPM Minium
@ 200 psi
19 - 6 STEERINGWJ
STEERING (Continued)

DIAGNOSIS AND TESTING - PUMP LEAKAGE
(1) Possible areas of pump leakage (Fig. 3).
STANDARD PROCEDURE
STANDARD PROCEDURE - INITIAL OPERATION
- 4.0L
WARNING: THE FLUID LEVEL SHOULD BE
CHECKED WITH ENGINE OFF TO PREVENT INJURY
FROM MOVING COMPONENTS.
CAUTION: Use MOPAR Power Steering Fluid or
equivalent. Do not use automatic transmission fluid
and do not overfill.
Wipe filler cap clean, then check the fluid level.
The dipstick should indicateCOLDwhen the fluid is
at normal ambient temperature.
(1) Fill the pump fluid reservoir to the proper level
and let the fluid settle for at least two minutes.
(2) Start the engine and let run for a few seconds
then turn engine off.
(3) Add fluid if necessary. Repeat the above proce-
dure until the fluid level remains constant after run-
ning the engine.
(4) Raise the front wheels off the ground.
(5) Slowly turn the steering wheel right and left,
lightly contacting the wheel stops at least 20 times.(6) Check the fluid level add if necessary.
(7) Lower the vehicle, start the engine and turn
the steering wheel slowly from lock to lock.
(8) Stop the engine and check the fluid level and
refill as required.
(9) If the fluid is extremely foamy or milky look-
ing, allow the vehicle to stand a few minutes and
repeat the procedure.
CAUTION: Do not run a vehicle with foamy fluid for
an extended period. This may cause pump damage.
STANDARD PROCEDURE - INITIAL OPERATION
- 4.7L
WARNING: THE FLUID LEVEL SHOULD BE
CHECKED WITH ENGINE OFF TO PREVENT INJURY
FROM MOVING COMPONENTS.
NOTE: Remove as much of the old fluid out of the
system as possible with a suction tool or by remov-
ing a hose, When a component has failed. Then
refill it with fresh fluid until it is clean. This may
have to be done more than once.
CAUTION: Use MOPAR Power Steering Fluid or
equivalent. Do not use automatic transmission fluid
and do not overfill.
Wipe filler cap clean, then check the fluid level.
The dipstick should indicateCOLDwhen the fluid is
at normal ambient temperature.
(1) Fill the pump fluid reservoir to the proper level
and let the fluid settle for at least two minutes.
(2) Start the engine and let run for a few seconds
then turn engine off.
(3) Add fluid if necessary. Repeat the above proce-
dure until the fluid level remains constant after run-
ning the engine.
(4) Raise the front wheels off the ground.
(5) Slowly turn the steering wheel right and left,
lightly contacting the wheel stops at least 20 times.
(6) Check the fluid level add if necessary.
(7) Lower the vehicle, start the engine, and use
the DRB III to activate the hydraulic fan on full fan
operation.
(8)
Turn the steering wheel slowly from lock to lock.
(9) Stop the engine, check the fluid level and refill
as required and repeat the process
CAUTION: Do not run a vehicle with foamy fluid for
an extended period. This may cause pump damage.
(10) If the fluid is extremely foamy or milky look-
ing, allow the vehicle to stand a few minutes and
repeat the procedure.
Fig. 3 4.0L Power Steering Pump
WJPUMP 19 - 33
PUMP (Continued)

(11) While the vehicle is in park, use the DRB III
to activate the hydraulic fan to full fan operation and
briefly rev the engine up to 3000 rpm to fully engage
the hydraulic fan.
(12) Check the fluid level add if necessary.
REMOVAL
REMOVAL - 4.0L ENGINE
(1) Remove serpentine drive belt,(Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(2) Remove pressure and return hoses from pump
and drain the pump.
(3)
Loosen the pump bracket bolt at the engine block.
(4) Remove 3 pump mounting bolts (Fig. 4)
through pulley access holes.
(5) Tilt pump downward and remove from engine.
(6) Remove pulley from pump.
REMOVAL - 4.7L ENGINE
(1) Remove the serpentine drive belt,(Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(2) Remove the pressure and return hoses from
pump and drain pump.
(3) Remove 3 pump mounting bolts through pulley
access holes (Fig. 5).
(4) Remove the pump from the vehicle.
INSTALLATION
INSTALLATION - 4.0L ENGINE
(1) Install pulley on pump.
(2) Install pump on the engine mounting bracket.
(3) Install 3 pump mounting bolts and tighten to
27 N´m (20 ft. lbs.).
(4) Tighten pump bracket bolt to 57 N´m (42 ft.
lbs.).
(5) Install the pressure line on the pump and
tighten to 28 N´m (21 ft. lbs.).
(6) Install the return hoses on pump.
(7) Install the drive belt,(Refer to 7 - COOLING/
ACCESSORY DRIVE/DRIVE BELTS - INSTALLA-
TION).
(8) Add power steering fluid,(Refer to 19 - STEER-
ING/PUMP - STANDARD PROCEDURE).
INSTALLATION - 4.7L ENGINE
(1) Position the pump on the left cylinder head
and install bolts through pulley access holes. Tighten
bolts to 28 N´m (21 ft. lbs.).
(2) Install the pressure and return hoses to pump.
(3) Install serpentine drive belt,(Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(4) Add power steering fluid,(Refer to 19 - STEER-
ING/PUMP - STANDARD PROCEDURE).
Fig. 4 PUMP MOUNTING ± 4.0L
1 - PUMP ASSEMBLY
2 - PUMP BRACKET
Fig. 5 Pump Mounting
1 - LEFT CYLINDER HEAD
2 - PUMP
19 - 34 PUMPWJ
PUMP (Continued)

INSTALLATION
(1) Position and install the power steering cooler
to the vehicle.
(2) Install the three mounting bracket bolts (Fig.
6).
(3) Reconnect the upper hose at cooler (Fig. 6).
(4) Reconnect the lower hose at cooler (Fig. 6).
(5) Connect negative battery cable to battery.
(6) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
(7) Start engine and check for leaks.
(8) Install the grille opening reinforcement panel
(9) Install the front fascia grille,(Refer to 13 -
FRAMES & BUMPERS/BUMPERS/FRONT FASCIA
- INSTALLATION).
HOSES - 4.0L
DESCRIPTION
DESCRIPTION - PRESSURE LINE
The hose consists of two metal ends and rubber
center section that contains a tuning cable. The
pump end uses a quick connect fitting. Lubircation
must be used on the quick connect nut and o-ring
when installing.
DESCRIPTION - RETURN LINE
Power steering return line is a hose which is
clamped at the pump and the gear.
OPERATION
OPERATION - PRESSURE LINE
Power steering pressure line, is used to transfer
high pressure power steering fluid, from the power
steering pump to the power steering gear on the
4.0L. The 4.7L power steering pressure line, is used
to transfer high pressure power steering fluid, from
the power steering pump to the engine cooling fan
and the steering gear.
OPERATION - RETURN LINE
Power steering return line, is used to transfer low
pressure power steering fluid, from the power steer-
ing gear to the power steering pump.
REMOVAL
(1) Drain the power steering fluid from the reser-
voir.
(2) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(3) Disconnect the power steering pressure hose
from the power steering pump and then the power
steering gear (Fig. 7).
(4) Disconnect the power steering return hose from
the power steering cooler and the reservoir.
(5) Remove the hoses from the vehicle.
INSTALLATION
(1) Install the hoses to the vehicle.
(2) Reconnect the power steering return hose to
the power steering cooler and the reservoir.
(3) Reconnect the power steering pressure hose to
the power steering pump and then the power steer-
ing gear.
(4) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(5) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
Fig. 7 POWER STEERING HOSES
1 - RETURN HOSE
2 - HIGH PRESSURE HOSE
3 - STEERING GEAR
WJPUMP 19 - 37
FLUID COOLER (Continued)