INTAKE MANIFOLDÐ2.5L ENGINE
REMOVAL
(1) Disconnect the battery negative cable.
(2) Remove the air inlet hose from the throttle
body and air cleaner.
(3) Loosen the accessory drive belt tension and re-
move the belt from the power steering pump.
(4) Remove the power steering pump and brackets
from the water pump and intake manifold. Support
power steering pump and bracket with mechanics
wire attached to the radiator upper crossmember.
(5) Remove the fuel tank filler cap to relieve the
fuel tank pressure.
(6) Install the fuel tank filler cap.
(7) Disconnect fuel supply and return tube from
the fuel rail (refer to Group 14, Fuel System - Quick
Connect Fittings).
(8) Disconnect the accelerator cable from the throt-
tle body and the holddown bracket.
CAUTION: When disconnecting the cruise control
connector at the throttle body, DO NOT pry the con-
nector off with pliers or screwdriver. Use finger
pressure only. Prying the connector off could break
it.
(9) Disconnect the electrical connectors. Pull the
harnesses away from the manifold.
²The throttle position sensor.
²The idle speed control motor.
²The coolant temperature sensor at the thermostat.
²The manifold air temperature sensor at the intake
manifold.
²The fuel injectors.
²The oxygen sensor.
(10) Disconnect the crankcase ventilation (CCV)
vacuum hose and manifold absolute pressure (MAP)
sensor vacuum hose connector at the intake mani-
fold.
(11) Disconnect vacuum hose from vacuum port on
the intake manifold.
(12) Disconnect CCV hose at the cylinder head
cover (Fig. 12).
(13) Remove the molded vacuum harness.
(14) Disconnect the vacuum brake booster hose at
the intake manifold.
(15) Remove bolts 2 through 5 securing the intake
manifold to the cylinder head (Fig. 11). Slightly
loosen bolt No.1 and nuts 6 and 7.
(16) Remove the intake manifold and gaskets.
Drain the coolant from the manifold.
CLEANING
Clean the intake manifold and cylinder head mat-
ing surfaces.DO NOT allow foreign material to
enter either the intake manifold or the ports in
the cylinder head.
INSTALLATION
(1) Install the new intake manifold gasket over the
locating dowels.
(2) Position the manifold in place and finger
tighten the mounting bolts.
(3) Tighten the fasteners in sequence and to the
specified torque (Fig. 11).
²Fastener No.1ÐTighten to 41 Nzm (30 ft. lbs.)
torque.
²Fasteners Nos.2 through 7ÐTighten to 31 Nzm (23
ft. lbs.) torque.
(4) Connect the fuel return and supply tube to the
connector next to the fuel rail. Push them into the
fitting until a click is heard. Verify that the connec-
tions are complete.
²First, ensure only the retainer tabs protrude from
the connectors.
²Second, pull out on the fuel tubes to ensure they
are locked in place.
(5) Connect the molded vacuum hoses to the vac-
uum port on the intake manifold and the cylinder
head cover.
(6) Connect the electrical connectors.
²The throttle position sensor.
²The automatic idle speed control motor.
²The coolant temperature sensor at the thermostat
housing.
²The fuel injectors.
²The air manifold temperature sensor.
²The oxygen sensor.
(7) Connect the CCV vacuum hose and MAP sen-
sor vacuum hose connectors to the throttle body.
(8) Install the power steering pump and bracket
assembly to the water pump and intake manifold.
(9) Connect the accelerator cable and cruise control
cable to the holddown bracket and the throttle arm.
Fig. 12 Crankcase Ventilation (CCV) Hose
(2.5L Engine)
11 - 8 EXHAUST SYSTEM AND INTAKE MANIFOLDJ
CAUTION: Ensure that the accessory drive belt is
routed correctly. Failure to do so can cause the wa-
ter pump to turn in the opposite direction resulting
in engine overheating. Refer to Group 7, Cooling
System for the proper procedure.
(10) Tension the accessory drive belt. Refer to
Group 7, Cooling System for the proper procedure.
(11) Connect the air inlet hose to the throttle body
and the air cleaner.
(12) Connect the battery negative cable.
(13) Start the engine and check for leaks.
INTAKE MANIFOLDÐ4.0L ENGINE
The intake and engine exhaust manifolds on the
4.0L engine must be removed and installed together.
The two manifolds use a common gasket at the cyl-
inder head.
REMOVAL
(1) Disconnect the battery negative cable.
(2) Remove air cleaner inlet hose from throttle
plate assembly.
(3) Remove the air cleaner assembly.
(4) Remove the throttle cable, cruise control cable (if
equipped) and the transmission line pressure cable.
(5) Disconnect all electrical connectors on the in-
take manifold.
(6) Disconnect and remove the fuel supply and re-
turn lines from the fuel rail assembly (refer to Group
14, Fuel System).
(7) Loosen the accessory drive belt (refer to Group
7, Cooling System). Loosen the tensioner.
(8) Remove the power steering pump and bracket
from the intake manifold and set aside.
(9) Remove the fuel rail and injectors (refer to
Group 14, Fuel System).
(10) Raise the vehicle.
(11) Disconnect the exhaust pipe from the engine
exhaust manifold. Discard the seal.
(12) Lower the vehicle.
(13) Remove the intake manifold and engine ex-
haust manifold.
CLEANING
Clean the mating surfaces of the cylinder head and
the manifold if the original manifold is to be installed.
If the manifold is being replaced, ensure all the fit-
ting, etc. are transferred to the replacement manifold.
INSTALLATION
(1) Install a new exhaust/intake manifold gasket
over the alignment dowels on the cylinder head.
(2) Position the engine exhaust manifold to the
cylinder head. Install fastener No.3 and finger
tighten at this time (Fig. 13).
(3) Install intake manifold on the cylinder head
dowels.(4) Install washers and fasteners Nos.1, 2, 4, 5, 8,
9, 10 and 11 (Fig. 13).
(5) Install washers and fasteners Nos.6 and 7 (Fig. 13).
(6) Tighten the fasteners in sequence and to the
specified torque (Fig. 13).
²Fasteners Nos.1 through 5ÐTighten to 33 Nzm (24
ft. lbs.) torque.
²Fasteners Nos.6 and 7ÐTighten to 31 Nzm (23 ft.
lbs.) torque.
²Fasteners Nos.8 through 11ÐTighten to 33 Nzm
(24 ft. lbs.) torque.
(7) Install the fuel rail and injectors.
(8) Install the power steering pump and bracket to the
intake manifold. Tighten the belt to specification. Refer
to Group 7, Cooling System for the proper procedures.
(9) Install the fuel supply and return lines to the
fuel rail assembly.Before connecting the fuel
lines to the fuel rail replace the O-rings in the
quick-connect fuel line couplings.Refer to Group
14, Fuel System for the proper procedure.
(10) Connect all electrical connections on the in-
take manifold.
(11) Connect the vacuum connector on the intake
manifold and install it in the bracket.
(12) Install throttle cable, cruise control cable (if
equipped).
(13) Install the transmission line pressure cable (if
equipped). Refer to Group 21, Transmission for the
adjustment procedures.
(14) Install air cleaner assembly.
(15) Connect air inlet hose to the throttle plate as-
sembly.
(16) Raise the vehicle on a side mounted hoist.
(17) Using a new seal, connect the exhaust pipe to
the engine exhaust manifold. Tighten the bolts to 31
Nzm (23 ft. lbs.) torque.
(18) Lower the vehicle.
(19) Connect the battery negative cable.
(20) Start the engine and check for leaks.
Fig. 13 Intake/Engine Exhaust Manifold Installation
(4.0L Engine)
JEXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 9
IDLE AIR CONTROL MOTOR TEST
Idle Air Control (IAC) Motor operation can be
tested using special exerciser tool number 7558 (Fig.
42).
CAUTION: Proper safety precautions must be taken
when testing the idle air control motor:
²Set the parking brake and block the drive wheels
²Route all tester cables away from the cooling fans,
drive belt, pulleys and exhaust components
²Provide proper ventilation while operating the en-
gine
²Always return the engine idle speed to normal be-
fore disconnecting the exerciser tool
(1) With the ignition OFF, disconnect the IAC mo-
tor wire connector at throttle body (Fig. 42).
(2) Plug the exerciser tool number 7558 harness
connector into the IAC motor.
(3) Connect the red clip of exerciser tool 7558 to
battery positive terminal. Connect the black clip tonegative battery terminal. The red light on the exer-
ciser tool will flash when the tool is properly con-
nected.
(4) Start engine.
When the switch on the tool is in the HIGH or
LOW position, the light on the tool will flash. This
indicates that voltage pulses are being sent to the
IAC stepper motor.
(5) Move the switch to the HIGH position. The en-
gine speed should increase. Move the switch to the
LOW position. The engine speed should decrease.
(a) If the engine speed changes while using the
exerciser tool, the IAC motor is functioning prop-
erly. Disconnect the exerciser tool and connect the
IAC motor wire connector to the stepper motor.
(b) If the engine speed does not change, turn the
ignition OFF and proceed to step (6). Do not discon-
nect exerciser tool from the IAC motor.
(6) Remove the IAC motor from the throttle body.
Do not remove IAC motor housing from throttle
body.
CAUTION: When checking IAC motor operation with
the motor removed from the throttle body, do not
extend the pintle (Fig. 43) more than 6.35 mm (.250
in). If the pintle is extended more than this amount,
it may separate from the IAC motor. The IAC motor
must be replaced if the pintle separates from the
motor.
(7) With the ignition OFF, cycle the exerciser tool
switch between the HIGH and LOW positions. Ob-
serve the pintle. The pintle should move in-and-out
of the motor.
(a) If the pintle does not move, replace the idle
air control motor. Start the engine and test the re-
placement motor operation as described in step (5).
(b) If the pintle operates properly, check the idle
air control motor bore in the throttle body bore for
blockage and clean as necessary. Reinstall the idle
air control motor and retest. If blockage is not
Fig. 41 Oxygen SensorÐTypical
Fig. 42 IAC Motor TestingÐTypical
Fig. 43 Idle Air Control (IAC) Motor Pintle
14 - 46 FUEL SYSTEMJ
STEERING
CONTENTS
page page
GENERAL INFORMATION.................. 1
MANUAL STEERING GEAR............... 35
NON-TILT STEERING COLUMN............ 50
POWER STEERING PUMP................. 9
POWER STEERING SYSTEM DIAGNOSIS..... 3
RECIRCULATING BALL POWER STEERING GEAR.19STEERING COLUMN GENERAL SERVICE.... 45
STEERING LINKAGEÐXJ................. 14
STEERING LINKAGEÐYJ................. 17
STEERING RHD........................ 69
TILT STEERING COLUMN................ 59
TORQUE SPECIFICATIONS................ 73
GENERAL INFORMATION
STEERING SYSTEM COMPONENTS
Jeep vehicles can have either a manual or power
steering system (Fig. 1). A recirculating-ball type
steering gear is used for both systems.
Power steering systems use;
²Steering gear
²Pressure and return fluid hoses and fittings
²Belt driven steering pump
²Integral or remote body mounted pump reservoir
POWER STEERING GEAR
The steering gear is mounted on the left frame rail.
The gear is joined to the intermediate shaft by a uni-
versal joint coupling. The coupling helps isolate noise
and road shock from the interior.
The major internal components of the gear are the:
²Rotary valve assembly
²Steering worm shaft
²Rack piston assembly
²Pitman shaft
The movement of these parts, while turning or
parking, is aided by hydraulic pressure and flow sup-plied by the pump. Manual steering is always avail-
able at times when the engine is not running or in
the event of pump or belt failure. Steering effort is
higher under such conditions.
The steering stub shaft, rotary valve, worm shaft,
and rack piston assembly are all in line. The oil pas-
sages are internal within the gear housing except for
pressure and return hoses between the gear and
pump.
The power steering gear has a recirculating ball
system. This acts as a rolling thread between the
worm shaft and rack piston. The worm shaft is sup-
ported by a thrust bearing at the lower end and a
bearing assembly at the upper end. When the worm
shaft is turned right, the rack piston moves up in
gear. Turning the worm shaft left moves the rack
piston down in gear. The rack piston teeth mesh with
the sector, which is part of the pitman shaft. Turning
the worm shaft turns the pitman shaft, which turns
the wheels through the steering linkage.
The control valve in the steering gear directs the
power steering fluid to either side of the rack piston.
The rack piston is assisted by hydraulic pressure. If
the steering system loses hydraulic pressure, the ve-
hicle can be controlled manually, but with higher
steering effort.
An identification code located on the side cover des-
ignates the gear ratio (Fig. 2).
²Code BH designates 14:1 ratio used in XJ vehicles
²Code BF designates 13-16:1 ratio used in YJ vehi-
cles
A recirculating-ball steering gear is used with the
power (assisted) steering system (Fig. 1). The power
steering gear can be adjusted and internally serviced.
POWER STEERING PUMP
Hydraulic pressure is provided for operation of the
power steering gear by a belt driven power steering
Fig. 1 Steering Gears
JSTEERING 19 - 1
pump. The power steering pump is a constant flow
rate and displacement, vane-type pump. The internal
parts in the housing operate submerged in fluid. The
flow control orifice is part of the high pressure line
fitting. The pressure relief valve inside the flow con-
trol valve limits the pump pressure.
Power steering pumps have different pres-
sure rates and are not interchangeable with
other pumps.
The power steering pump is connected to the steer-
ing gear via high pressure and return hose. The
pump shaft has a pressed-on drive pulley that is belt
driven by the crankshaft pulley (Fig. 3).
XJ vehicles with 2.5L engines and all YJ vehicles:
The reservoir is mounted at the front left side of the
engine compartment. XJ vehicles equipped with a
4.0L engine have the reservoir attached to the pump
body with spring clips.
STEERING COLUMNS
Two general types of steering columns are installed
on Jeep vehicles: a fixed, non-tilt column and a tilt
column (Fig. 4).
The ignition key/lock cylinder is located in the
steering column. When the key/lock cylinder is
turned to the LOCK position, the ignition switch and
steering shaft cannot be operated. For vehicles with
an automatic transmission, the lock mechanism also
prevents operation of the gear shift mechanism.The center, slip-type intermediate shaft is attached
to the steering gear and steering column shaft with
universal joints.
Both types of steering columns have anti-theft pro-
visions. They are energy-absorbing.
Fig. 3 TC Series Pump With Integral Reservoir
Fig. 4 Steering Columns
Fig. 2 Ratio Code Location
19 - 2 STEERINGJ
POWER STEERING SYSTEM DIAGNOSIS
PUMP PRESSURE TEST
(1) Check belt tension and adjust as necessary.
(2) Disconnect high pressure hose at gear or pump.
Use a container for dripping fluid.
(3) Connect Gauge 7617 (J21567) to both hoses us-
ing adapter fitting (Fig. 1). Connect spare pressure
hose to gear or pump.
(4) Open the test valve completely.
(5) Start engine and let idle.
(6) Check fluid level, add fluid as necessary.
(7) 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).CAUTION: The following test procedure involves
testing maximum pump pressure output and flow
control valve operation. Do not leave valve closed
for more than 5 seconds as the pump could be
damaged.
(8) Close valve fully three times and record highest
pressure indicated each time.All three readings
must be above 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.
Pump damage will result.
(9) Open the test valve, turn steering wheel ex-
treme left and right positions against the stops.
Record the highest indicated pressure at each posi-
tion. Compare readings to specifications. If highest
output pressures are not the same against either
stop, the gear is leaking internally and must be re-
paired.
Fig. 1 Pressure Test Gauge
PUMP OPERATING SPECIFICATIONS
JSTEERING 19 - 3
(7) After installation, inspect and test for fluid
leaks.
PUMP REPLACEMENT
REMOVAL
CAUTION: The drive belt tension must be released
before removing the pump. If the belt is not loos-
ened, the pump pulley could be damaged.
(1) Remove serpentine drive belt. Refer to Group 7,
Cooling for additional information.
(2) Place a drain pan under pump.
(3) Remove pressure and return hoses from pump.
Refer to Pressure and Return Hose Replacement in
this section.
(4) Remove 2 rear bracket-to-pump bolts (Fig. 4).
(5) Remove lower nut at adjustment bracket.
(6) Remove adjuster bolt.
(7) Remove upper pivot bolt.
(8) Tilt pump forward and remove pump and front
bracket assembly from engine bracket.
(9) Remove adjuster collar at lower stud on pump
bracket.
(10) Remove pulley from pump. Refer to Drive Pul-
ley Replacement in this section (Fig. 5).
(11) Remove 3 front bracket-to-pump bolts.
Fig. 2 Power Steering Hose XJ 4 Cylinder
Fig. 3 Power Steering Hose XJ 6 Cylinder
19 - 10 STEERINGJ
INSTALLATION
(1) Install 3 front bracket-to-pump bolts. Tighten
to 28 Nzm (21 ft. lbs.) torque.
(2) Install pulley on pump. Refer to Drive Pulley
Replacement in this section (Fig. 6).
(3) Install adjuster collar on adjuster bracket stud
(Fig. 4).
(4) Tilt pump forward and install pump onto en-
gine bracket.
(5) Install upper pivot bolt.
(6) Install lower adjuster bolt.
(7) Install lower adjuster stud nut.
(8) Install 2 rear engine bracket to pump bolts.
Tighten to 28 Nzm (21 ft. lbs.) torque.
(9) Install the serpentine drive belt. Refer to Group
7, Cooling for additional information.
(10) Install the pressure and return hoses to
pump. Refer to Pressure and Return Hose Replace-
ment in this section.
(11) Add power steering fluid. Refer to Power
Steering Pump Initial Operation in this section.
DRIVE PULLEY REPLACEMENT
REMOVAL
(1) Remove power steering pump. Refer to Pump
Replacement in this section.(2) Remove the drive pulley with Puller C-4333 (J-
25034-B) (Fig. 5).
Do not hammer on any part of drive pulley,
damage will occur to the pump and pulley.
INSTALLATION
(1) Install the pulley with Installer C-4063 (J-
25033-B) (Fig. 6). Do not use the tool adapters.
Fig. 4 Pump Mounting (4.0L I-6)
Fig. 5 Remove Drive Pulley (Typical)
JSTEERING 19 - 11