The resistance values of the IAT sensor is the same
as for the Engine Coolant Temperature (ECT) sensor.
REMOVAL
2.4L
The intake manifold air temperature (IAT) sensor
is installed into the intake manifold plenum at the
rear end of the intake manifold (Fig. 14).
(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. 14)
or (Fig. 15) and rotate sensor about 1/4 turn counter-
clockwise for removal.
(4) Check condition of sensor o-ring (Fig. 15).
3.7L
The intake manifold air temperature (IAT) sensor
is installed into the left side of intake manifold ple-
num (Fig. 16).
(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. 16)
or (Fig. 15) and rotate sensor about 1/4 turn counter-
clockwise for removal.
(4) Check condition of sensor o-ring.
Fig. 14 IAT SENSOR LOCATION-2.4L
1 - RELEASE TAB
2 - IAT SENSOR
3 - PRESS HERE FOR REMOVAL
4 - ELECTRICAL CONNECTOR
5 - REAR END OF INTAKE MANIFOLD
Fig. 15 IAT SENSOR TAB / O-RING
1 - IAT SENSOR
2 - SENSOR O-RING
3 - RELEASE TAB
Fig. 16 IAT SENSOR LOCATION- 3.7L
1 - IAT SENSOR
2 - RELEASE TAB
3 - ELECTRICAL CONNECTOR
KJFUEL INJECTION 14 - 37
INTAKE AIR TEMPERATURE SENSOR (Continued)
INSTALLATION
2.4L
The intake manifold air temperature (IAT) sensor
is installed into the intake manifold plenum at the
rear end of the intake manifold.
(1) Check condition of sensor o-ring.
(2) Clean sensor mounting hole in intake manifold.
(3) Position sensor into intake manifold and rotate
clockwise until past release tab.
(4) Install electrical connector.
3.7L
The intake manifold air temperature (IAT) sensor
is installed into the left side of intake manifold ple-
num (Fig. 16).
(1) Check condition of sensor o-ring.
(2) Clean sensor mounting hole in intake manifold.
(3) Position sensor into intake manifold and rotate
clockwise until past release tab (Fig. 16).
(4) Install electrical connector.
MAP SENSOR
DESCRIPTION
2.4L
The Manifold Absolute Pressure (MAP) sensor is
mounted into the rear of the intake manifold with 1
screw.
3.7L
The Manifold Absolute Pressure (MAP) sensor is
mounted into the front of the intake manifold with 2
screws.
OPERATION
The MAP sensor is used as an input to the Power-
train Control Module (PCM). It contains a silicon
based sensing unit to provide data on the manifold
vacuum that draws the air/fuel mixture into the com-
bustion chamber. The PCM requires this information
to determine injector pulse width and spark advance.
When manifold absolute pressure (MAP) equals
Barometric pressure, the pulse width will be at max-
imum.
A 5 volt reference is supplied from the PCM and
returns a voltage signal to the PCM that reflects
manifold pressure. The zero pressure reading is 0.5V
and full scale is 4.5V. For a pressure swing of 0±15
psi, the voltage changes 4.0V. To operate the sensor,
it is supplied a regulated 4.8 to 5.1 volts. Ground is
provided through the low-noise, sensor return circuit
at the PCM.The MAP sensor input is the number one contrib-
utor to fuel injector pulse width. The most important
function of the MAP sensor is to determine baromet-
ric pressure. The PCM needs to know if the vehicle is
at sea level or at a higher altitude, because the air
density changes with altitude. It will also help to cor-
rect for varying barometric pressure. Barometric
pressure and altitude have a direct inverse correla-
tion; as altitude goes up, barometric goes down. At
key-on, the PCM powers up and looks at MAP volt-
age, and based upon the voltage it sees, it knows the
current barometric pressure (relative to altitude).
Once the engine starts, the PCM looks at the voltage
again, continuously every 12 milliseconds, and com-
pares the current voltage to what it was at key-on.
The difference between current voltage and what it
was at key-on, is manifold vacuum.
During key-on (engine not running) the sensor
reads (updates) barometric pressure. A normal range
can be obtained by monitoring a known good sensor.
As the altitude increases, the air becomes thinner
(less oxygen). If a vehicle is started and driven to a
very different altitude than where it was at key-on,
the barometric pressure needs to be updated. Any
time the PCM sees Wide Open Throttle (WOT), based
upon Throttle Position Sensor (TPS) angle and RPM,
it will update barometric pressure in the MAP mem-
ory cell. With periodic updates, the PCM can make
its calculations more effectively.
The PCM uses the MAP sensor input to aid in cal-
culating the following:
²Manifold pressure
²Barometric pressure
²Engine load
²Injector pulse-width
²Spark-advance programs
²Shift-point strategies (certain automatic trans-
missions only)
²Idle speed
²Decel fuel shutoff
The MAP sensor signal is provided from a single
piezoresistive element located in the center of a dia-
phragm. The element and diaphragm are both made
of silicone. As manifold pressure changes, the dia-
phragm moves causing the element to deflect, which
stresses the silicone. When silicone is exposed to
stress, its resistance changes. As manifold vacuum
increases, the MAP sensor input voltage decreases
proportionally. The sensor also contains electronics
that condition the signal and provide temperature
compensation.
The PCM recognizes a decrease in manifold pres-
sure by monitoring a decrease in voltage from the
reading stored in the barometric pressure memory
cell. The MAP sensor is a linear sensor; meaning as
pressure changes, voltage changes proportionately.
14 - 38 FUEL INJECTIONKJ
INTAKE AIR TEMPERATURE SENSOR (Continued)
THROTTLE CONTROL CABLE
REMOVAL
2.4L
CAUTION: Be careful not to damage or kink the
cable core wire (within the cable sheathing) while
servicing accelerator pedal or throttle cable.
(1) From inside vehicle, hold up accelerator pedal.
Remove plastic cable retainer (clip) and throttle cable
core wire from upper end of pedal arm (Fig. 26).
Plastic cable retainer snaps into top of pedal arm.
(2) Remove cable core wire at pedal arm.
(3) From inside vehicle, remove metal clip holding
cable to dashpanel (Fig. 26).
(4) Remove air box at throttle body.
(5) Unsnap cable from dashpanel routing clip.
(6) Remove cable housing from dash panel and
pull into engine compartment.
(7) Hold throttle in wide open position. While held
in this position, slide throttle cable pin (Fig. 27) from
throttle body bellcrank.(8) Using a pick or small screwdriver, press release
tab (Fig. 27) to release plastic cable mount from
bracket.Press on tab only enough to release
cable from bracket. If tab is pressed too much,
it will be broken.To remove throttle cable from
throttle body bracket, slide cable towards front of
vehicle.
(9) Remove throttle cable from vehicle.
3.7L
CAUTION: Be careful not to damage or kink the
cable core wire (within the cable sheathing) while
servicing accelerator pedal or throttle cable.
(1) From inside vehicle, hold up accelerator pedal.
Remove plastic cable retainer (clip) and throttle cable
core wire from upper end of pedal arm (Fig. 28).
Plastic cable retainer snaps into top of pedal arm.
(2) Remove cable core wire at pedal arm.
(3) From inside vehicle, remove metal clip holding
cable to dashpanel (Fig. 28).
(4) Remove air box at throttle body.
(5) Unsnap cable from dashpanel routing clip.
(6) Remove cable housing from dash panel and
pull into engine compartment.
(7) Hold throttle in wide open position. While held
in this position, slide throttle cable pin (Fig. 29) from
throttle body bellcrank.
Fig. 26 ACCELERATOR PEDAL/BRACKET
ASSEMBLY
1 - METAL THROTTLE CABLE CLIP
2 - THROTTLE CABLE
3 - PLASTIC CABLE RETAINER
4 - PEDAL/BRACKET ASSEMBLY
5 - PEDAL MOUNTING NUTS (2)
6 - PEDAL MOUNTING STUDS (2)
Fig. 27 THROTTLE CABLE, PIN, RELEASE TAB-2.4L
1 - MOUNTING BRACKET
2 - SPEED CONTROL CABLE
3 - THROTTLE CABLE
4 - RELEASE TAB
5 - CABLE PINS
6 - BELLCRANK
KJFUEL INJECTION 14 - 45
(8) Using a pick or small screwdriver, press release
tab (Fig. 30) to release plastic cable mount from
bracket.Press on tab only enough to release
cable from bracket. If tab is pressed too much,
it will be broken.Slide plastic mount (Fig. 30)
towards right side of vehicle to remove throttle cable
from throttle body bracket.
(9) Remove throttle cable from vehicle.
INSTALLATION
(1) Slide accelerator cable plastic mount into throt-
tle body mounting bracket. Continue sliding until
release tab (Fig. 30) is aligned to hole in mounting
bracket.
(2) Hold throttle in wide open position. While held
in this position, slide throttle cable pin (Fig. 29) into
throttle body bellcrank.
(3) Push cable housing into rubber grommet and
through opening in dash panel.
(4) From inside vehicle, install metal clip holding
cable to dashpanel (Fig. 28).
(5) From inside vehicle, slide throttle cable core
wire into opening (slot) in top of pedal arm.
(6) Push plastic cable retainer (clip) into pedal arm
opening until it snaps in place.
(7) Install air box to throttle body.
(8) Before starting engine, operate accelerator
pedal to check for any binding.
Fig. 28 ACCELERATOR PEDAL/BRACKET
ASSEMBLY
1 - METAL THROTTLE CABLE CLIP
2 - THROTTLE CABLE
3 - PLASTIC CABLE RETAINER
4 - PEDAL/BRACKET ASSEMBLY
5 - PEDAL MOUNTING NUTS (2)
6 - PEDAL MOUNTING STUDS (2)
Fig. 29 THROTTLE CABLE PIN-3.7L
1 - THROTTLE CABLE PIN
2 - THROTTLE BODY BELLCRANK
3 - PUSH UP HERE
Fig. 30 THROTTLE CABLE RELEASE TAB-3.7L
1 - THROTTLE CABLE
2 - RELEASE TAB
3 - PICK OR SCREWDRIVER
4 - PLASTIC CABLE MOUNT
14 - 46 FUEL INJECTIONKJ
THROTTLE CONTROL CABLE (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
COLUMN
TABLE OF CONTENTS
page page
COLUMN
DESCRIPTION..........................5
OPERATION - SERVICE PRECAUTIONS......5
REMOVAL.............................5
INSTALLATION..........................7
SPECIFICATIONS
TORQUE CHART......................8
SPECIAL TOOLS
STEERING COLUMN....................8
IGNITION SWITCH
DESCRIPTION..........................8
DIAGNOSIS AND TESTING - IGNITION
SWITCH.............................8
REMOVAL
IGNITION SWITCH REMOVAL.............9INSTALLATION
IGNITION SWITCH INSTALLATION.........9
KEY-IN IGNITION SWITCH
DESCRIPTION.........................10
DIAGNOSIS AND TESTING - KEY-IN IGNITION
SWITCH............................10
LOCK CYLINDER
REMOVAL.............................10
INSTALLATION.........................11
INTERMEDIATE SHAFT
REMOVAL.............................11
INSTALLATION.........................11
STEERING WHEEL
REMOVAL.............................12
INSTALLATION.........................12
COLUMN
DESCRIPTION
The standard non-tilt and tilt steering column has
been designed to be serviced as an assembly. The col-
umn is connected to the steering gear with a one
piece shaft. The upper half has a support bearing
mounted to a bracket. The bracket mounts to the
frame rail with two nuts. The shaft is serviceable.
The key cylinder, switches, clock spring, trim shrouds
and steering wheel are serviced separately.
OPERATION - SERVICE PRECAUTIONS
Safety goggles should be worn at all times when
working on steering columns.
To service the steering wheel, switches or airbag,
refer to Electrical - Restraints and follow all WARN-
INGS and CAUTIONS.
WARNING: THE AIRBAG SYSTEM IS A SENSITIVE,
COMPLEX ELECTRO-MECHANICAL UNIT. BEFORE
ATTEMPTING TO DIAGNOSE, REMOVE OR INSTALL
THE AIRBAG SYSTEM COMPONENTS YOU MUST
FIRST DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE. THEN WAIT TWOMINUTES FOR THE SYSTEM CAPACITOR TO DIS-
CHARGE. FAILURE TO DO SO COULD RESULT IN
ACCIDENTAL DEPLOYMENT OF THE AIRBAG AND
POSSIBLE PERSONAL INJURY. THE FASTENERS,
SCREWS, AND BOLTS, ORIGINALLY USED FOR
THE AIRBAG COMPONENTS, HAVE SPECIAL COAT-
INGS AND ARE SPECIFICALLY DESIGNED FOR THE
AIRBAG SYSTEM. THEY MUST NEVER BE
REPLACED WITH ANY SUBSTITUTES. ANYTIME A
NEW FASTENER IS NEEDED, REPLACE WITH THE
CORRECT FASTENERS PROVIDED IN THE SERVICE
PACKAGE OR FASTENERS LISTED IN THE PARTS
BOOKS.REMOVAL
(1) Position front wheelsstraight ahead.
(2) Remove and isolate the negative ground cable
from the battery.
(3) Remove the airbag, (Refer to 8 - ELECTRICAL/
RESTRAINTS/DRIVER AIRBAG - REMOVAL).
NOTE: If equipped with cruise control, disconnect
clock spring harness from the cruise switch har-
ness on the steering wheel.
KJCOLUMN 19 - 5
REMOVAL
IGNITION SWITCH REMOVAL
The ignition key must be in the key cylinder for
cylinder removal. The key cylinder must be removed
first before removing ignition switch.
(1) Remove lower steering column cover screws
and remove cover.
(2) Remove lock cylinder.(Refer to 19 - STEERING/
COLUMN/KEY/LOCK CYLINDER - REMOVAL).
(3) Remove the multi-function switch.
(4) Disconnect the electrical connector at the rear
of the ignition switch.
(5) Remove the ignition switch mounting screw
(Fig. 7). Use tamper proof torx bit to remove the
screw.
(6) Pull the ignition switch straight out to remove
from the locking tabs (Fig. 8)
INSTALLATION
IGNITION SWITCH INSTALLATION
The ignition key must be in the key cylinder for
cylinder installation. The key cylinder must be
aligned with the ignition switch for installation.
(1) Before installing ignition switch, rotate the slot
in the switch to the ON position (Fig. 9).
(2) Connect the electrical connector to rear of igni-
tion switch. Make sure that locking tab is fully
seated into wiring connector.
(3) Position the switch to the column and install
tamper proof screw. Tighten screw to 2 N´m (17 in.
lbs.).(4) Install the lock cylinder (Refer to 19 - STEER-
ING/COLUMN/KEY/LOCK CYLINDER - INSTALLA-
TION).
(5) Test the operation of the lock cylinder for
smooth rotating.
(6) Install the multi-function switch.
(7) Install steering column lower cover.
Fig. 7 IGNITION SWITCH MOUNTING SCREW
1 - Tamper Proof Torx Screw
2 - Ignition Switch
Fig. 8 IGNITION SWITCH TABS
1 - Ignition Switch
2 - Locking Tabs
Fig. 9 IGNITION SWITCH ON POSITION
1 - Ignition Switch
2 - Rotate to On Position
KJCOLUMN 19 - 9
IGNITION SWITCH (Continued)
GEAR
TABLE OF CONTENTS
page page
GEAR
DESCRIPTION.........................13
OPERATION...........................13
REMOVAL
REMOVAL - 4WD......................13
REMOVAL - 2WD......................14
INSTALLATION
INSTALLATION - 4WD..................14INSTALLATION - 2WD..................14
SPECIFICATIONS
TORQUE CHART......................15
SPECIAL TOOLS
OUTER TIE ROD END REMOVAL TOOL....15
GEAR
DESCRIPTION
A rack and pinion steering gear (Fig. 1) is made up
of two main components, the pinon shaft and the
rack. The gear cannot be adjusted or internally ser-
viced. If a malfunction or a fluid leak occurs, the gear
must be replaced as an assembly.
OPERATION
The steering column intermediate shaft is attached
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, which are
connected to the steering knuckles to change the
direction of the front wheels.
REMOVAL
REMOVAL - 4WD
(1) Siphon the power steering fluid from the power
steering reservoir.
(2) Lock the steering wheel to prevent spinning of
the clockspring.
(3) Raise and support the vehicle.
(4) Remove the skid plate from under the front
end to gain access to the gear (Refer to 13 - FRAME
& BUMPERS/FRAME/FRONT SKID PLATE -
REMOVAL).
(5) Remove the front tire and wheel assemblies.
NOTE: Mark the alignment adjusting cams for eas-
ier installation.
(6) Remove the lower control arms. (Refer to 2 -
SUSPENSION/FRONT/LOWER CONTROL ARM -
REMOVAL).
(7) Remove the front axle. (Refer to 3 - DIFFER-
ENTIAL & DRIVELINE/FRONT AXLE - REMOV-
AL).
(8) Remove the tie rod end nuts.
(9) Separate tie rod ends from the knuckles with
Puller C-3894-A.
(10) Remove the intermediate shaft lower coupler
bolt and slide the coupler off the gear (Fig. 2).
(11) Remove power steering pressure hose bracket
(Fig. 3).
(12) Remove the power steering lines from the
gear (Fig. 2).
(13) Remove the mounting bolts from the gear to
the front cradle (Fig. 3).
(14) Remove the steering gear from the vehicle.
Fig. 1 Rack & Pinion Steering Gear
1 - TIE ROD - INNER
2 - TIE ROD - INNER
3 - TIE ROD END - OUTER LH
4 - BOOTS
5 - TIE ROD END - OUTER RH
KJGEAR 19 - 13