Engine DODGE TOWN AND COUNTRY 2001 Service Manual

Injector opens (start of injection)
The solenoid valve is energized with the pickup
current which serves to ensure that it open quickly.
The force exerted by the triggered solenoid now
exceeds that of the valve spring and the armature
opens the bleed orifice. Almost immediately, the high-level pick-up current is reduced to the lower holding
current required for the electromagnet. This is possi-
ble due to the magnetic circuit's air gap now being
smaller. When the bleed orifice opens, fuel can flow
from the valve control chamber into the cavity situ-
ated above it, and from there via the fuel return to
the tank. The bleed orifice prevents complete pres-
sure balance, and the pressure in the valve control
chamber sinks as a result. This leads to the pressure
in the valve-control chamber being lower than that in
the nozzle's chamber volume which is still at the
same pressure level as the rail. The reduced pressure
in the valve-control chamber causes a reduction in
the force exerted on the control plunger, the nozzle
needle open as a result, and injection starts (Fig. 2).
Injector opens fully
The control plunger reaches its upper stop where it
remains supported by a cushion of fuel which is gen-
erated by the flow of fuel between the bleed and feed
orifices. The injector nozzle has now opened fully,
and the fuel is injected into the combustion chamber
at a pressure almost equal to that in the fuel rail
(Fig. 2).
Injector closes (end of injection)
As soon as the solenoid valve is no longer trig-
gered, the valve spring forces the armature down-
wards and the ball closes the bleed orifice. The
armature is a 2±piece design. Here, although the
armature plate is guided by a driver shoulder in its
downward movement, it can ªoverspringº with the
return spring so that it exerts no downwards-acting
forces on the armature and the ball. The closing of
the bleed orifice lead to pressure build up in the con-
trol chamber via the input from the feed orifice. This
pressure is the same as that in the rail and exerts an
increased force on the control plunger through its
end face. This force, together with that of the spring,
now exceeds the force exerted by the chamber volume
and the nozzle needle closes. Injection ceases as soon
as the nozzle needle comes up against its bottom stop
again (Fig. 2).
REMOVAL
(1) Disconnect negative battery cable.
(2) Remove engine cover (Refer to 9 - ENGINE
COVER - REMOVAL).
(3) Disconnect injector electrical connector.
(4) Remove fuel return line from injector (Fig. 3).
(5) Remove fuel injector high pressure line (Fig. 3).
(6) Remove fuel injector retainer and retaining
bolt (Fig. 3).
(7) Remove fuel injector from cylinder head (Fig.
3).
Fig. 2 INJECTOR COMPONENTS
1 - INJECTOR CLOSED (AT-REST STATUS)
2 - ELECTRICAL CONNECTION
3 - TRIGGERING ELEMENT (SOLENOID VALVE)
4 - FUEL INLET (HIGH PRESSURE) FROM THE RAIL
5 - VALVE BALL
6 - BLEED ORIFICE
7 - FEED ORIFICE
8 - VALVE CONTROL CHAMBER
9 - VALVE CONTROL PLUNGER
10 - FEED PASSAGE TO THE NOZZLE
11 - NOZZLE NEEDLE
RGFUEL INJECTION14a-11
FUEL INJECTOR (Continued)
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INSTALLATION
NOTE: Be sure the copper washer is installed on
end of injector before installing in cylinder head.
(1) Install fuel injector in cylinder head.
(2) Install fuel injector retainer and bolt (Fig. 3).
Torque bolt to 32.4 N´m.
(3) Install fuel injector high pressure line (Fig. 3).(4) Install fuel return line to injector (Fig. 3).
(5) Connect fuel injector electrical connector.
(6) Install engine cover (Refer to 9 - ENGINE
COVER - INSTALLATION).
(7) Connect negative battery cable.
ACCELERATOR PEDAL
POSITION SENSOR
DESCRIPTION
The accelerator pedal position sensor mounts to
the accelerator pedal bracket (Fig. 4).
OPERATION
The accelerator pedal position sensor contains a
potentiometer that is operated by the accelerator
pedal. As the accelerator pedal is depressed and
released, the sensor provides a variable voltage sig-
nal to the engine control module. This voltage signal
is directly proportional to accelerator pedal position.
When the pedal is fully depressed, the voltage signal
is high.
REMOVAL - PEDAL POSITION SENSOR (LHD)
(1) Disconnect negative battery cable.
(2) Disconnect pedal position sensor electrical con-
nector (Fig. 4).
Fig. 3 FUEL SYSTEM COMPONENTS
1 - FUEL RAIL RETAINING BOLT
2 - FUEL RAIL RETAINING STUD
3 - FUEL RAIL RETURN LINE
4 - FUEL RAIL
5 - FUEL RAIL SUPPLY LINE
6 - IDLER PULLEY
7 - CRANKSHAFT PULLEY
8 - CRANKSHAFT PULLEY RETAINING BOLTS
9 - BELT TENSIONER RETAINING BOLT
10 - BELT TENSIONER
11 - FUEL INJECTOR RETAINER
12 - FUEL INJECTOR RETURN LINE
13 - FUEL INJECTOR RETAINING BOLT
14 - FUEL INJECTORS
15 - FUEL INJECTOR HIGH PRESSURE SUPPLY LINESFig. 4 ACCELERATOR PEDAL POSITION SENSOR
LOCATION (TYPICAL)
1 - ACCELERATOR PEDAL POSITION SENSOR ELECTRICAL
CONNECTOR
2 - ACCELERATOR PEDAL POSITION SENSOR
3 - ACCELERATOR PEDAL
4 - ACCELERATOR PEDAL MOUNTING BRACKET
14a - 12 FUEL INJECTIONRG
FUEL INJECTOR (Continued)
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(3) Remove 2 pedal position sensor retaining nuts
(Fig. 4).
(4) Remove pedal position sensor from vehicle.
REMOVAL - PEDAL POSITION SENSOR (RHD)
(1) Disconnect negative battery cable.
(2) Disconnect pedal position sensor electrical con-
nector (Fig. 4).
(3) Remove 2 pedal position sensor retaining nuts
(Fig. 4).
(4) Remove pedal position sensor from vehicle.
INSTALLATION - PEDAL POSITION SENSOR
(LHD)
(1) Position pedal position sensor in vehicle.
(2) Install pedal position sensor retaining nuts
(Fig. 4).
(3) Connect pedal position sensor electrical connec-
tor (Fig. 4).
(4) Connect negative battery cable.
INSTALLATION - PEDAL POSITION SENSOR
(RHD)
(1) Position pedal position sensor in vehicle.
(2) Install 2 pedal position sensor retaining nuts
(Fig. 4).
(3) Connect pedal position sensor electrical connec-
tor (Fig. 4).
(4) Connect negative battery cable.
BOOST PRESSURE SENSOR
DESCRIPTION
The boost pressure sensor is mounted to the top of
the intake manifold. The sensor allows the ECM to
monitor air pressure within the intake manifold. The
boost pressure sensor is also used as an intake air
temperature sensor (Fig. 5).
OPERATION
When the intake manifold pressure is low (high
vacuum) sensor voltage output is 0.25-1.8 volts at the
ECM. When the intake manifold pressure is high due
to turbo boost, sensor voltage output is 2.0-4.7 volts.
The sensor receives a 5-volts reference from the
ECM. Sensor ground is also provides by the ECM.
The ECM uses boost pressure combined with intake
air temerature to determine the volume of air enter-
ing the engine.
DIAGNOSIS AND TESTING - BOOST PRESSURE
SENSOR
If the boost pressure sensor fails, the ECM records
a DTC into memory and continues to operate theengine in one of the three limp-in modes. When the
ECM is operating in this mode, a loss of power will
be present, as if the turbocharger was not operating.
The best method for diagnosing faults with the boost
pressure sensor is with the DRB IIItscan tool. Refer
to the Diesel Powertrain Diagnostic Manual for more
information.
Refer to On-Board Diagnostics in Emissions Con-
trol System for a list of Diagnostic Trouble Codes
(DTC's) for certain fuel system components.
INTAKE AIR TEMPERATURE
SENSOR
DESCRIPTION
The boost pressure sensor/intake air temperature
sensor is located in the top of the intake manifold
(Fig. 6). The intake air temperature sensor is used to
measure the intake air temperature. The intake air
temperture sensor is a dual purpose sensor. It is also
used as a boost pressure sensor.
OPERATION
The intake air temperature sensor is a negative
temperature coefficient (NTC) thermistor (resistance
varies inversly with temperature). This means at
cold air temperature its resistance is high, sothe volt-
age signal will be high. As intake air temperature
increases, sensor resistance decreases and the signal
voltage will be low. This allows the sensor to provide
an analog voltage signal (0.2-4.8 volts) to the ECM.
REMOVAL
(1) Disconnect negative battery cable.
(2) Remove engine cover retaining bolts and cover-
(Refer to 9 - ENGINE COVER - REMOVAL).
Fig. 5 BOOST PRESSURE SENSOR/INTAKE AIR
TEMPERATURE SENSOR
RGFUEL INJECTION14a-13
ACCELERATOR PEDAL POSITION SENSOR (Continued)
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(3) Disconnect intake air temperature electrical
connector.
(4) Remove intake air temperature sensor retain-
ing screws and sensor (Fig. 6).
INSTALLATION
(1) Install intake air temperature sensor and
retaining bolts (Fig. 6). Torque to 5.4 N´m.
(2) Connect intake air temperature sensor.
(3) Install engine cover and retaining bolts (Refer
to 9 - ENGINE COVER - INSTALLATION).
CRANKSHAFT POSITION
SENSOR
DESCRIPTION
The crankshaft position sensor is mounted in the
right rear of the engine block below the turbocharger
(Fig. 7). This sensor is used to detect engine speed.
OPERATION
The crankshaft position sensor is a magnetic
pickup type sensor that generates an ac signal. The
sensor contains a permanent magent and a coil of
wire. The sensor generates an ac signal each time a
notch in the reluctor wheel on the crankshaft passesacross the permanent magnet. The ECM calculates
engine speed based on the frequency of the ac signal.
The ECM supplies the sensor ground.
MASS AIR FLOW (MAF)
SENSOR
DESCRIPTION
The Mass Air Flow (MAF) Sensor is mounted
inline in the air intake between the air filter and the
turbocharger (Fig. 8).
Fig. 6 BOOST PRESSURE SENSOR/INTAKE AIR
TEMPERATURE SENSOR LOCATION
1 - FUEL RAIL
2 - FUEL PRESSURE SENSOR
3 - INTAKE AIR TEMPERATURE/BOOST PRESSURE SENSOR
4 - CYLINDER HEAD COVER/INTAKE MANIFOLD
Fig. 7 CRANKSHAFT POSITION SENSOR
1 - CRANKSHAFT POSITION SENSOR
2 - CRANKSHAFT POSITION SENSOR ELECTRICAL
CONNECTOR
Fig. 8 MASS AIR FLOW (MAF) SENSOR
14a - 14 FUEL INJECTIONRG
INTAKE AIR TEMPERATURE SENSOR (Continued)
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OPERATION
The ECM uses the mass air flow (MAF) sensor to
measure air density. The MAF sensor contains a
ceramic element. A signal voltage is provided to the
element. As engine speed increases, airflow across
the ceramic element increases. Changes in air flow
and air density cause the temperature of the ceramic
element to fluxuate. The ceramic element changes
resistance respectively to changes in temperature.
The change in resistance varies the signal voltage
output to the ECM. The diesel power relay supplies
battery power the to MAF sensor. Ground is provided
by the ECM. The MAF sensor signal is provided by
the ECM.
REMOVAL
(1) Disconnect negative battery cable.
(2) Disconnect MAF sensor electrical connector
(Fig. 9).
(3) Loosen MAF sensor retaining clamps (Fig. 9).
(4) Remove MAF sensor from airduct (Fig. 9).
INSTALLATION
(1) Install MAF sensor in airduct (Fig. 9).
(2) Tighten retaining clamps (Fig. 9).(3) Connect MAF sensor electrical connector (Fig.
9).
(4) Connect negative battery cable.
Fig. 9 MASS AIR FLOW (MAF) SENSOR LOCATION
1 - MAF SENSOR ELECTRICAL CONNECTOR
2 - RETAINING CLAMPS
3 - MASS AIR FLOW (MAF) SENSOR
4 - AIR CLEANER HOUSING
RGFUEL INJECTION14a-15
MASS AIR FLOW (MAF) SENSOR (Continued)
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STEERING
TABLE OF CONTENTS
page page
STEERING
DESCRIPTION............................1
OPERATION.............................1
DIAGNOSIS AND TESTING..................1
POWER STEERING SYSTEM FLOW AND
PRESSURE TEST........................1STEERING SYSTEM DIAGNOSIS CHARTS....3
SPECIFICATIONS.........................9
SPECIAL TOOLS..........................9
COLUMN...............................10
GEAR.................................17
PUMP.................................24
STEERING
DESCRIPTION - POWER STEERING SYSTEM
This vehicle comes with power steering as stan-
dard equipment and it is the only steering system
available. The power steering system consists of
these major components:
²POWER STEERING PUMP
²POWER STEERING GEAR
²POWER STEERING FLUID RESERVOIR
²POWER STEERING FLUID SUPPLY HOSE
²POWER STEERING FLUID PRESSURE HOSE
²POWER STEERING FLUID RETURN HOSE
²POWER STEERING FLUID COOLER
For information on the first two components, refer
to their respective sections within this service man-
ual group. Information on all other components can
be found in POWER STEERING PUMP.
OPERATION - POWER STEERING SYSTEM
Turning of the steering wheel is converted into linear
(side-to-side) travel through the meshing of the helical
pinion teeth with the rack teeth within the steering
gear. The lateral travel pushes and pulls the tie rods to
change the direction of the vehicle's front wheels.
Power assist steering is provided by a belt driven
rotary type pump. It directs fluid through power
steering fluid hoses to the power steering gear where
it is used to assist the driver's turning effort.
Manual steering control of the vehicle can be main-
tained if power steering assist is lost. However, under
this condition, steering effort is significantly increased.
DIAGNOSIS AND TESTING - POWER STEERING
SYSTEM FLOW AND PRESSURE TEST
ALL ENGINES
The following procedure is to be used to test the
operation of the power steering system on this vehi-
cle. This test will provide the flow rate of the power
steering pump along with the maximum relief pres-sure. This test is to be performed any time a power
steering system problem is present to determine if
the power steering pump or power steering gear is
not functioning properly. The following flow and pres-
sure test is performed using the Power Steering Ana-
lyzer Kit, Special Tool 6815 (Fig. 1), hoses, Special
Tools 6905 and 6959, and fittings from adapter kit,
Special Tool 6893.
Assemble hoses on Power Steering Analyzer, Spe-
cial Tool 6815, as shown. Install Pressure Hose, Spe-
cial Tool 6905 (in 6893 kit), in the inlet fitting on
Power Steering Analyzer. Install Pressure Hose, Spe-
cial Tool 6713 (in 6815 kit) on Pressure Hose, Special
Tool 6905. Install Pressure Hose, Special Tool 6959,
in the outlet fitting on Power Steering Analyzer.
Install the following adapters from Adapter Set,
Special Tool 6893 (Fig. 2), on the analyzer hose ends:
Install Adapter Fitting, Special Tool 6844, on Pres-
sure Hose, Special Tool 6713. Install Adapter Fitting,
Special Tool 6826, on Pressure Hose, Special Tool
6959.
Fig. 1 Power Steering Analyzer With Hoses Installed
1 - OUTLET
2 - SPECIAL TOOL 6815
3 - INLET
RSSTEERING19-1
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CAUTION: To prevent personal injury, safety gog-
gles should be worn at all times when performing
any test procedures on the power steering pump or
power steering gear.
The following procedure is to be used to test the
operation of the power steering system on the vehi-
cle.
(1) Check belt tension and adjust as necessary.
(2) Disconnect the power steering fluid pressure
hose from the power steering pump (Fig. 3) (Fig. 4).
(3) Connect Adapter Fitting, Special Tool 6844,
attached to pressure hose from inlet (gauge end) ofPower Steering Analyzer to the pressure fitting on
the power steering pump.
(4) Connect vehicle power steering fluid pressure
hose to Adapter Fitting, Special Tool 6826, which
should be already installed in the outlet hose (valve
end) of Power Steering Analyzer.
(5) Completely open valve on Power Steering Ana-
lyzer.
(6) Start engine and let idle long enough to circu-
late power steering fluid through the analyzer and
hoses, until the air is out of the fluid. Shut off
engine.
(7) Check power steering fluid level and add fluid
as necessary. Start engine again and let idle.
(8) Gauge should read below 862 kPa (125 psi). If
above, inspect the hoses for restrictions and repair as
necessary. The initial pressure should be in the range
of 345-552 kPa (50-80 psi). The flow meter should
read between 1.3 and 1.9 GPM.
CAUTION: The following test procedure involves
testing maximum pump pressure output and flow
control valve operation. Do not leave valve closed
for more than five seconds as the pump could be
damaged.
Fig. 2 Power Steering Analyzer Adapters 6893
Fig. 3 Pressure Hose Connection To Power Steering
Pump - 2.4L
1 - POWER STEERING FLUID RETURN HOSE
2 - POWER STEERING PUMP
3 - POWER STEERING FLUID PRESSURE HOSE
Fig. 4 SUPPLY & PRESSURE HOSES AT PUMP -
3.3L/3.8L
1 - PRESSURE HOSE AND FITTING
2 - SUPPLY HOSE AND CLAMP
3 - POWER STEERING PUMP
19 - 2 STEERINGRS
STEERING (Continued)
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NOTE: * There is some noise in all power steering
systems. One of the most common is a hissing
sound evident when turning the steering wheel
when at a standstill or when parking and the steer-
ing wheel is at the end of its travel. Hiss is a very
high frequency noise similar to that experienced
while slowly closing a water tap. The noise is
present in every valve and results when high veloc-ity fluid passes valve orifice edges. There is no
relationship between this noise and the perfor-
mance of the steering system.
NOTE: ** Power steering pump growl results from
the development of high pressure fluid flow. Nor-
mally this noise level should not be high enough to
be objectionable.
STEERING WHEEL FEEL
CONDITION POSSIBLE CAUSES CORRECTION
STEERING WHEEL/
COLUMN CLICKING,
CLUNKING OR RATTLING.1. Loose steering coupling pinch
bolt.1. Replace pinch bolt and torque to
specifications.
2. Steering column bearings. 2. Replace steering column.
STEERING WHEEL HAS
FORE AND AFT
LOOSENESS.1. Steering wheel retaining nut not
properly tightened and torqued.1. Tighten the steering wheel retaining nut
to its specified torque.
2. Steering column lower bearing
spring retainer slipped on steering
column shaft.2. Replace steering column.
3. Loose steering column to
instrument panel fasteners.3. Tighten fasteners to specified torque.
STEERING WHEEL OR
DASH VIBRATES DURING
LOW SPEED OR
STANDSTILL STEERING
MANEUVERS.1. Air in the fluid of the power
steering system.1. Bleed air from system following the
power steering pump initial operation
service procedure.*
2. Tires not properly inflated. 2. Inflate tires to the specified pressure.
3. Excessive engine vibration. 3. Ensure that the engine is running
properly.
4. Loose tie rod end jam nut. 4. Tighten the inner to outer tie rod jam nut
to the specified torque.
5.Overcharged air conditioning
system.5.Check air conditioning pump head
pressure and correct as necessary.
STEERING CATCHES,
STICKS IN CERTAIN
POSITIONS OR IS
DIFFICULT TO TURN.1. Low power steering fluid level. 1. Fill power steering fluid reservoir to
specified level and check for leaks.
2. Tires not inflated to specified
pressure.2. Inflate tires to the specified pressure.
3. Lack of lubrication in front lower
control arm ball joints.3. Lubricate ball joints if ball joints are not a
lubricated-for-life type ball joint. If ball joint
is a lubricated-for-life ball joint, replace ball
joint.
4. Worn or binding lower control arm
ball joint.4. Replace lower control arm ball joint.
RSSTEERING19-5
STEERING (Continued)
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SPECIFICATIONS
POWER STEERING FASTENER TORQUE
DESCRIPTION TORQUE
Power Steering Pump:
Flow Control Valve
Pressure Fitting75 N´m (55 ft. lbs.)
Mounting Bolts 54 N´m (40 ft. lbs.)
Rear Bracket To Engine
Mounting Bolts54 N´m (40 ft. lbs.)
Steering Gear:
Mounting Bolts 183 N´m (135 ft. lbs.)
Tie Rod Steering Knuckle
Nut75 N´m (55 ft. lbs.)
Tie Rod Jam Nut 75 N´m (55 ft. lbs.)
Coupling Pinch Bolt 28 N´m (250 in. lbs.)
Power Steering Fluid
Hoses:
Hose Tube Nuts 31 N´m (275 in. lbs.)
Routing Bracket Bolts 23 N´m (200 in. lbs.)
SPECIAL TOOLS
POWER STEERING
Power Steering Analyzer 6815
Adapters, Power Steering Analyzer 6893
HOSE, POWER STEERING ANALYZER 6959
RSSTEERING19-9
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ing gear. This travel pushes and pulls the tie rods to
change the direction of the vehicle's front wheels.
Power assist steering provided by the power steer-
ing pump is controlled by an open center, rotary type
control valve which directs oil from the pump to
either side of the integral rack piston upon demand.
Road feel is controlled by the diameter of a torsion
bar which initially steers the vehicle. As required
steering effort increases, as in a turn, the torsion bar
twists, causing relative rotary motion between the
rotary valve body and the valve spool. This move-
ment directs oil behind the integral rack piston
which, in turn, builds up hydraulic pressure and
assists in the turning effort.
Manual steering control of the vehicle can be main-
tained if power steering assist is lost. However,
under this condition, steering effort is significantly
increased.
SERVICE WARNINGS AND CAUTIONS
WARNING: POWER STEERING FLUID, ENGINE
PARTS AND EXHAUST SYSTEM MAY BE
EXTREMELY HOT IF ENGINE HAS BEEN RUNNING.
DO NOT START ENGINE WITH ANY LOOSE OR DIS-
CONNECTED HOSES. DO NOT ALLOW HOSES TO
TOUCH HOT EXHAUST MANIFOLD OR CATALYST.
WARNING: FLUID LEVEL SHOULD BE CHECKED
WITH THE ENGINE OFF TO PREVENT PERSONAL
INJURY FROM MOVING PARTS.
CAUTION: When the system is open, cap all open
ends of the hoses, power steering pump fittings or
power steering gear ports to prevent entry of for-
eign material into the components.
REMOVAL - GEAR
CAUTION: Positioning the steering column in the
locked position will prevent the clockspring from
being accidentally over-extended when the steering
column is disconnected from the intermediate
steering coupler.
(1) Remove cap from power steering fluid reser-
voir.
(2) Using a siphon pump, remove as much fluid as
possible from the power steering fluid reservoir.
(3) With the ignition key in the locked position
turn the steering wheel to the left until the steering
wheel is in the locked position.
(4) With the vehicle on the ground, disconnect the
steering column shaft coupler from the steering gear
intermediate coupler (Fig. 2).(5) Raise vehicle on jack stands or centered on a
frame contact type hoist. See Hoisting in the Lubri-
cation and Maintenance section of this service man-
ual, for the required lifting procedure to be used for
this vehicle.
(6) Remove front wheel and tire assemblies.
(7) Remove hoses at power steering cooler and
allow fluid to drain.
(8) On both sides of vehicle, remove nut attaching
outer tie rod end to steering knuckle (Fig. 3).
Remove nut by holding tie rod end stud with a
socket while loosening and removing nut with
wrench.
(9) Remove both tie rod ends from steering knuck-
les, using Puller, Special Tool C-3894±A (Fig. 4).
(10) Remove the lower control arm rear bushing
retainer bolts located on each side of each lower con-
trol arm rear bushing.
NOTE: The bolts fastening the cradle crossmember
reinforcement are of two different thread sizes. Note
the location of the various sizes.
(11) Remove the bolts attaching the cradle cross-
member reinforcement to the front suspension cradle
crossmember (Fig. 5). Remove the 2 bolts fastening
the reinforcement and rear of cradle crossmember to
the body of the vehicle. Remove the reinforcement.
(12) If the vehicle is equipped with All-Wheel-
Drive, remove the power transfer unit (Refer to 21 -
TRANSMISSION/TRANSAXLE/POWER TRANSFER
UNIT - REMOVAL).
Fig. 2 Steering Column Shaft To Intermediate Shaft
Attachment
1 - STEERING COLUMN SHAFT COUPLER
2 - NUT
3 - SAFETY PIN
4 - INTERMEDIATE SHAFT
5 - PINCH BOLT
19 - 18 GEARRS
GEAR (Continued)
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