2002 JEEP GRAND CHEROKEE transmission cooling li e

8W-30 FUEL/IGNITION SYSTEM
Component Page
A/C Compressor Clutch Relay . . . 8W-30-23, 35, 39, 41, 42
A/C Pressure Transducer........ 8W-30-21, 42, 45, 31
Accelerator Pedal Position Sensor........ 8W-30-37, 48
Adjustable Pedals Module................ 8W-30-33
Adjustable Pedals Motor/Sensor Assembly.... 8W-30-33
Adjustable Pedals Switch................ 8W-30-33
Auto Shut Down Relay...... 8W-30-8, 9, 12, 24, 25, 26,
27, 28, 29, 30, 35, 39, 41
Battery Temperature Sensor.......... 8W-30-2, 11, 50
Body Control Module................... 8W-30-46
Boost Pressure Sensor.................. 8W-30-45
Brake Lamp Switch.............. 8W-30-4, 5, 32, 51
Camshaft Position Sensor........ 8W-30-18, 19, 20, 49
Capacitor........................... 8W-30-12
Capacitor No. 1....................... 8W-30-16
Capacitor No. 2....................... 8W-30-17
Clockspring...................... 8W-30-4, 5, 38
Coil On Plug No. 1.................... 8W-30-17
Coil On Plug No. 2.................... 8W-30-16
Coil On Plug No. 3.................... 8W-30-17
Coil On Plug No. 4.................... 8W-30-16
Coil On Plug No. 5.................... 8W-30-17
Coil On Plug No. 6.................... 8W-30-16
Coil On Plug No. 7.................... 8W-30-17
Coil On Plug No. 8.................... 8W-30-16
Coil Rail............................ 8W-30-12
Controller Antilock Brake........... 8W-30-2, 36, 51
Crankcase Heater..................... 8W-30-35
Crankshaft Position Sensor....... 8W-30-18, 19, 20, 49
Data Link Connector............... 8W-30-6, 7, 46
Diagnostic Junction Port.......... 8W-30-6, 7, 33, 46
EGR Solenoid........................ 8W-30-50
Electronic Speed Control Servo........... 8W-30-4, 5
Engine Control Module.... 8W-30-34, 35, 36, 37, 38, 39,
40, 41, 42, 43, 44, 45,
46, 47, 48, 49, 50, 51
Engine Coolant Temperature Sensor . . . 8W-30-21, 22, 47
Engine Oil Pressure Sensor......... 8W-30-21, 22, 45
Engine Starter Motor Relay......... 8W-30-18, 19, 39
EVAP/Purge Solenoid.................. 8W-30-4, 5
Fuel Injector No. 1............... 8W-30-13, 15, 44
Fuel Injector No. 2............... 8W-30-13, 14, 44
Fuel Injector No. 3............... 8W-30-13, 15, 44
Fuel Injector No. 4............... 8W-30-13, 14, 44
Fuel Injector No. 5............... 8W-30-13, 15, 44
Fuel Injector No. 6.................. 8W-30-13, 14
Fuel Injector No. 7..................... 8W-30-15
Fuel Injector No. 8..................... 8W-30-14
Fuel Pressure Sensor................... 8W-30-37
Fuel Pressure Solenoid.................. 8W-30-47
Fuel Pump Module.................... 8W-30-10
Fuel Pump Relay.................. 8W-30-8, 9, 10
Fuel Tank Module..................... 8W-30-45
Fuse 6........................... 8W-30-8, 42
Fuse 10............................ 8W-30-33
Fuse 11............................ 8W-30-43
Fuse 12......................... 8W-30-8, 9, 40
Fuse 13............................ 8W-30-41
Fuse 16 . . 8W-30-24, 25, 26, 27, 28, 29, 30, 35, 37, 39, 41
Component Page
Fuse 19............................. 8W-30-9
Fuse 21......................... 8W-30-4, 5, 32
Fuse 22............................ 8W-30-34
Fuse 23............................ 8W-30-39
Fuse 24............................. 8W-30-9
Fuse 26..................... 8W-30-8, 12, 41, 47
Fuse 31............................ 8W-30-39
G103....................... 8W-30-8, 34, 39, 46
G104......................... 8W-30-26, 27, 30
G105........................... 8W-30-35, 39
G108........................... 8W-30-23, 43
G123.............................. 8W-30-50
G300............................ 8W-30-4, 33
G301............................ 8W-30-5, 10
Generator...................... 8W-30-3, 23, 35
Glow Plug No. 1...................... 8W-30-42
Glow Plug No. 2...................... 8W-30-43
Glow Plug No. 3...................... 8W-30-42
Glow Plug No. 4...................... 8W-30-43
Glow Plug No. 5...................... 8W-30-42
Glow Plug Relay No. 1............. 8W-30-35, 42, 43
Glow Plug Relay No. 2............. 8W-30-35, 42, 43
Hydraulic Cooling Module . . . 8W-30-3, 24, 25, 30, 31, 43
Idle Air Control Motor.................. 8W-30-20
Intake Air Temperature Sensor....... 8W-30-21, 22, 38
Intake Port Swirl Actuator............... 8W-30-39
Junction Block......... 8W-30-4, 5, 8, 9, 32, 33, 39, 40
Knock Sensor........................ 8W-30-11
Leak Detection Pump................... 8W-30-23
Manifold Absolute Pressure Sensor.... 8W-30-20, 21, 22
Mass Air Flow Sensor.................. 8W-30-37
Output Speed Sensor.................... 8W-30-2
Oxygen Sensor 1/1 Upstream...... 8W-30-25, 26, 28, 29
Oxygen Sensor 1/2 Downstream.... 8W-30-24, 25, 26, 30
Oxygen Sensor 2/1 Upstream........ 8W-30-27, 28, 29
Oxygen Sensor 2/2 Downstream...... 8W-30-24, 27, 30
Oxygen Sensor Downstream Relay . . 8W-30-24, 26, 27, 30
Park/Neutral Position Switch............. 8W-30-33
Power Distribution Center...... 8W-30-8, 9, 12, 24, 25,
26, 27, 28, 29, 30, 34, 35,
37, 39, 41, 42, 43, 47
Powertrain Control Module . . . 8W-30-2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12, 13, 14, 15, 16, 17,
18, 19, 20, 21, 22, 23, 24, 25,
26, 27, 28, 29, 30, 31, 32
Shifter Assembly............... 8W-30-2, 32, 38, 40
Speed Control Switch No. 1........... 8W-30-4, 5, 38
Speed Control Switch No. 2........... 8W-30-4, 5, 38
Throttle Position Sensor................. 8W-30-20
Transfer Case Position Sensor........... 8W-30-8, 51
Transmission Control
Module............. 8W-30-6, 7, 20, 23, 32, 36, 40
Transmission Control Relay.............. 8W-30-23
Transmission Solenoid................ 8W-30-3, 21
Transmission Solenoid/TRS Assembly....... 8W-30-33
Viscous/Cabin Heater................... 8W-30-39
Viscous/Cabin Heater Relay...... 8W-30-35, 39, 41, 42
Wastegate Solenoid.................... 8W-30-35
Water In Fuel Sensor................... 8W-30-50
WJ8W-30 FUEL/IGNITION SYSTEM 8W - 30 - 1

CONNECTOR NAME/
NUMBERCOLOR LOCATION FIG.
Fuel Pump Module (Gas) BK Near Fuel Tank 33, 35
Fuel Tank Module Diesel) BK Near Fuel Tank 33, 35
Generator (Diesel) LTGY At Generator 8
Generator (Gas) BK At Generator N/S
Glove Box Lamp BK Inside Glove Box 19, 20, 22
Headlamp Leveling Switch
(Built-Up-Export)WT Driver Side of Instrument Panel 20
Hood Ajar Switch BK Left Side of Engine Compartment 3, 4
Horn No.1 BK Right Front Fascia 5
Horn No.2 BK Right Front Fascia 5
Hydraulic Cooling Module BK Right Front of Engine Compartment 5
Idle Air Control Motor BK Left Side of Engine Near Throttle
Body13
Ignition Switch - C1 WT On Steering Column 23
Ignition Switch - C2 BK On Steering Column 23
Input Speed Sensor (4.7L) BK Left Side of Transmission 16
Instrument Cluster WT At Instrument Cluster 19, 20
Intake Air Temperature Sensor
(Gas)GY Left Side of Engine 9, 13
Intake Air Temperature Sensor
(Diesel)BK Near T/O for Crankcase Heater 8
Intake Port Swirl Actuator
(Diesel)BK Right Rear of Engine Compartment N/S
Intrusion Transceiver Module
(Built-up-Export)BK In The Overhead N/S
Junction Block - C1 BK At Junction Block 30, 31, 33
Junction Block - C2 BK At Junction Block 30, 31
Junction Block - C3 BK At Junction Block 21, 22, 30
Junction Block - C4 WT At Junction Block 30, 31
Junction Block - C5 WT At Junction Block 30, 31
Knock Sensor (4.7L High
Output)BK Right Rear Side of Engine, Near
Coil on Plug No.8N/S
Leak Detection Pump (Except
Built-Up-Export)Left Front Wheel Opening 3
Left Courtesy Lamp BK Left Side of Instrument Panel 21 22, 23
Left Curtain Airbag BK Near Left C Pillar 37
Left Door Handle Courtesy
LampBK At Lamp N/S
Left Fog Lamp BK At Lamp 3, 4
Left Front Door Speaker WT In Left Front Door 24, 27
Left Front Impact Sensor BK Left Front Frame Near Windshield
Washer Pump3, 4
Left Front Park Lamp WT At Lamp N/S
8W - 91 - 6 8W-91 CONNECTOR/GROUND/SPLICE LOCATIONWJ
CONNECTOR/GROUND/SPLICE LOCATION (Continued)

CAUTION: DO NOT use engine or transmission oil,
mineral spirits, or kerosene.
(3) Honing should be done by moving the hone up
and down fast enough to get a crosshatch pattern.
The hone marks should INTERSECT at 40É to 60É
for proper seating of rings (Fig. 3).
(4) A controlled hone motor speed between 200 and
300 RPM is necessary to obtain the proper cross-
hatch angle. The number of up and down strokes per
minute can be regulated to get the desired 40É to 60É
angle. Faster up and down strokes increase the cross-
hatch angle.
(5) After honing, it is necessary that the block be
cleaned to remove all traces of abrasive. Use a brush
to wash parts with a solution of hot water and deter-
gent. Dry parts thoroughly. Use a clean, white, lint-
free cloth to check that the bore is clean. Oil the
bores after cleaning to prevent rusting.
STANDARD PROCEDURE - ENGINE CORE AND
OIL GALLERY PLUGS
Using a blunt tool such as a drift and a hammer,
strike the bottom edge of the cup plug. With the cup
plug rotated, grasp firmly with pliers or other suit-
able tool and remove plug (Fig. 4).CAUTION: Do not drive cup plug into the casting as
restricted cooling can result and cause serious
engine problems.
Thoroughly clean inside of cup plug hole in cylin-
der block or head. Be sure to remove old sealer.
Lightly coat inside of cup plug hole with Mopart
Stud and Bearing Mount. Make certain the new plug
is cleaned of all oil or grease. Using proper drive
plug, drive plug into hole so that the sharp edge of
the plug is at least 0.5 mm (0.020 in.) inside the
lead-in chamfer.
It is not necessary to wait for curing of the sealant.
The cooling system can be refilled and the vehicle
placed in service immediately.
REMOVAL
(1) Disconnect the battery negative cable.
(2) Mark the hinge locations on the hood panel for
alignment reference during installation. Remove the
engine compartment lamp. Remove the hood.
(3) Remove the radiator drain cock and radiator
cap to drain the coolant. DO NOT waste usable cool-
ant. If the solution is clean, drain the coolant into a
clean container for reuse.
(4) Remove the upper radiator hose and coolant
recovery hose.
(5) Remove the lower radiator hose.
(6) Remove upper radiator support retaining bolts
and remove radiator support.
Fig. 3 Cylinder Bore Crosshatch Pattern
1 - CROSSHATCH PATTERN
2 - INTERSECT ANGLE
Fig. 4 Core Hole Plug Removal
1 - CYLINDER BLOCK
2 - REMOVE PLUG WITH PLIERS
3 - STRIKE HERE WITH HAMMER
4 - DRIFT PUNCH
5 - CUP PLUG
WJENGINE - 4.0L 9 - 11
ENGINE - 4.0L (Continued)

(7) Remove the fan assembly from the water pump
(Refer to 7 - COOLING/ENGINE/RADIATOR FAN -
REMOVAL).
(8) Remove the fan shroud.
(9) Disconnect the transmission fluid cooler lines
(automatic transmission).
(10) Discharge the A/C system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE).
(11) Remove the service valves and cap the com-
pressor ports.
(12) Remove the radiator or radiator/condenser (if
equipped with A/C).
(13) Disconnect the heater hoses at the engine
thermostat housing and water pump.
(14) Disconnect the accelerator cable, transmission
line pressure cable and speed control cable (if
equipped) from the throttle body.
(15) Remove cables from the bracket and secure
out of the way.
(16) Disconnect the body ground at the engine.
(17) Disconnect the following connectors and
secure their harness out of the way.
²Power steering pressure switch
²Coolant temperature sensor
²Six (6) fuel injector connectors
²Intake air temperature sensor
²Throttle position sensor
²Map sensor
²Crankshaft position sensor
²Oxygen sensor
²Camshaft position sensor
²Generator connector and B+ terminal wire
(18) Disconnect the coil rail electrical connections
and the oil pressure switch connector.
(19) Perform the fuel pressure release procedure
(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY -
STANDARD PROCEDURE).
(20) Disconnect the fuel supply line at the injector
rail (Refer to 14 - FUEL SYSTEM/FUEL DELIVERY/
QUICK CONNECT FITTING - STANDARD PROCE-
DURE).
(21) Remove the fuel line bracket from the intake
manifold.
(22) Remove the air cleaner assembly (Fig. 5).
(23) Disconnect the hoses from the fittings at the
steering gear.
(24) Drain the pump reservoir.
(25) Cap the fittings on the hoses and steering
gear to prevent foreign objects from entering the sys-
tem.
(26) Raise and support the vehicle.
(27) Disconnect the wires from the engine starter
motor solenoid.(28) Remove the engine starter motor (Refer to 8 -
ELECTRICAL/STARTING/STARTER MOTOR -
REMOVAL).
(29) Disconnect the oxygen sensor from the
exhaust pipe.
(30) Disconnect the exhaust pipe from the mani-
fold.
(31) Remove the exhaust pipe support.
(32) Remove the bending brace (Refer to 9 -
ENGINE/ENGINE BLOCK/STRUCT SUPPORT -
REMOVAL).
(33) Remove the engine flywheel/converter housing
access cover.
(34) Mark the converter and drive plate location.
(35) Remove the converter-to-drive plate bolts.
(36) Remove the upper engine flywheel/converter
housing bolts and loosen the bottom bolts.
(37) Remove the engine mount cushion-to-engine
compartment bracket bolts.
(38) Lower the vehicle.
(39) Attach a lifting device to the engine.
(40) Raise the engine off the front supports.
(41) Place a support or floor jack under the con-
verter (or engine flywheel) housing.
(42) Remove the remaining converter (or engine
flywheel) housing bolts.
(43) Lift the engine out of the engine compart-
ment.
Fig. 5 Air Cleaner Assembly
1 - POWER STEERING PUMP
2 - AIR CLEANER ASSEMBLY
9 - 12 ENGINE - 4.0LWJ
ENGINE - 4.0L (Continued)

INSTALLATION
CAUTION: When installing the engine into a vehicle
equipped with an automatic transmission, be care-
ful not to damage the trigger wheel on the engine
flywheel.
(1) Attach a lifting device to the engine and lower
the engine into the engine compartment. For easier
installation, it may be necessary to remove the
engine mount bracket as an aid in alignment of the
engine to the transmission.
(2) Align the transmission torque converter hous-
ing with the engine.
(3) Loosely install the converter housing lower
bolts and install the next higher bolt and nut on each
side.
(4) Tighten all 4 bolts finger tight.
(5) Install the engine mount brackets (if removed).
(6) Lower the engine and engine mount brackets
onto the engine compartment cushions. Install the
bolts and finger tighten the nuts.
(7) Remove the engine lifting device.
(8) Raise and support the vehicle.
(9) Install the remaining engine flywheel/converter
housing bolts. Tighten all bolts to 38 N´m (28 ft. lbs.)
torque.
(10) Install the converter-to-drive plate bolts.
(11) Ensure the installation reference marks are
aligned.
(12) Install the engine flywheel/converter housing
access cover.
(13) Install the exhaust pipe support and tighten
the screw.
(14) Install the engine bending brace (Refer to 9 -
ENGINE/ENGINE BLOCK/STRUCT SUPPORT -
INSTALLATION).
(15) Tighten the engine mount-to-bracket bolts.
(16) Connect the vehicle speed sensor wire connec-
tions and tighten the screws.
(17) Connect the exhaust pipe to the manifold.
(18) Install the engine starter motor (Refer to 8 -
ELECTRICAL/STARTING/STARTER MOTOR -
INSTALLATION).
(19) Connect the wires to the engine starter motor
solenoid.
(20) Lower the vehicle.
(21) Connect all the vacuum hoses and wire con-
nectors identified during engine removal.
(22) Remove protective caps from the power steer-
ing hoses.
(23) Connect the hoses to the fittings at the steer-
ing gear. Tighten the nut to 52 N´m (38 ft. lbs.)
torque.
(24) Fill the pump reservoir with fluid.(25) Inspect the fuel supply line o-ring(s) and
replace if necessary. Connect fuel supply line to injec-
tior rail and verify connection by pulling outward on
the line.
(26) Install the fuel line bracket to the intake
manifold.
(27) Connect the coil rail electrical connectors and
oil pressure switch connector.
(28) Connect the following electrical connectors:
²Power steering pressure switch
²Coolant temperature sensor
²Six (6) fuel injector connectors
²Intake air temperature sensor
²Throttle position sensor
²Map sensor
²Crankshaft position sensor
²Oxygen sensor
²Camshaft position sensor
²Generator connector and B+ terminal wire
(29) Connect all previously removed vacuum hoses.
(30) Connect the body ground strap.
(31) Install the throttle, transmission line pres-
sure, and speed control cables to their mounting
bracket and connect them to the throttle body.
(32) Connect the heater hoses at the engine ther-
mostat housing and water pump.
(33) Install the fan assembly (Refer to 7 - COOL-
ING/ENGINE/RADIATOR FAN - INSTALLATION).
(34) Place the fan shroud in position over the fan.
(35) Install the radiator (Refer to 7 - COOLING/
ENGINE/RADIATOR - INSTALLATION).
(36) Connect the service valves to the A/C com-
pressor ports, if equipped with A/C.
(37) Charge the air conditioner system (Refer to 24
- HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE).
(38) Connect the radiator hoses and automatic
transmission fluid cooler pipes, if equipped.
(39) Install the fan shroud to the radiator or radi-
ator/condenser (if equipped with A/C).
(40) Install upper radiator support.
(41) Connect the upper radiator hose and tighten
the clamp.
(42) Connect the lower radiator hose and tighten
the clamp.
(43) Fill crankcase with engine oil. (Refer to
LUBRICATION & MAINTENANCE/FLUID CAPACI-
TIES - SPECIFICATIONS) for correct capacities.
(44) Fill the cooling system with reusable coolant
or new coolant (Refer to 7 - COOLING - STANDARD
PROCEDURE).
(45) Align the hood to the scribe marks. Install the
hood.
(46) Install the air cleaner assembly.
(47) Install the battery and connect the battery
cable.
WJENGINE - 4.0L 9 - 13
ENGINE - 4.0L (Continued)

(12) Install the push rods, rocker arms, pivots and
bridges in the order they were removed (Refer to 9 -
ENGINE/CYLINDER HEAD/ROCKER ARM /
ADJUSTER ASSY - INSTALLATION).
(13) Install the engine cylinder head cover (Refer
to 9 - ENGINE/CYLINDER HEAD/CYLINDER
HEAD COVER(S) - INSTALLATION).
(14) Attach the air conditioner compressor mount-
ing bracket to the engine cylinder head and block.
Tighten the bolts to 40 N´m (30 ft. lbs.) torque.
(15) Attach the air conditioning compressor to the
bracket. Tighten the bolts to 27 N´m (20 ft. lbs.)
torque.
CAUTION: The serpentine drive belt must be routed
correctly. Incorrect routing can cause the water
pump to turn in the opposite direction causing the
engine to overheat.
(16) Install the serpentine drive belt. (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(17) Install the air cleaner and ducting.
(18) Connect the hoses to the engine thermostat
housing and fill the cooling system to the specified
level (Refer to 7 - COOLING - STANDARD PROCE-
DURE).
(19) The automatic transmission throttle linkage
and cable must be adjusted after completing the
engine cylinder head installation (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC - AW4/
THROTTLE VALVE CABLE - ADJUSTMENTS).
(20) Install the temperature sending unit and con-
nect the wire connector.
(21) If equipped with air conditioning, install A/C
compressor (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING/A/C COMPRESSOR -
INSTALLATION) and charge A/C system (Refer to 24
- HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE).
(22) Connect negative cable to battery.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN DIRECT
LINE WITH THE FAN. DO NOT PUT HANDS NEAR
THE PULLEYS, BELTS OR FAN. DO NOT WEAR
LOOSE CLOTHING.
(23) Operate the engine with the radiator cap off.
Inspect for leaks and continue operating the engine
until the engine thermostat opens. Add coolant, if
required.CYLINDER HEAD COVER(S)
DESCRIPTION
The cylinder head cover (Fig. 11) is made of
stamped steel and incorporates the Crankcase Venti-
lation (CCV) Hoses and the oil fill opening.
REMOVAL
The cylinder head cover is isolated from the cylin-
der head via grommets and a reusable molded rubber
gasket. The grommet and limiter are retained in the
cylinder head cover.
(1) Disconnect negative cable from battery.
(2) Disconnect the Crankcase Ventilation (CCV)
vacuum hose from engine cylinder head cover.
(3) Disconnect the fresh air inlet hose from the
engine cylinder head cover.
(4) Disconnect the accelerator, transmission, and
speed (if equipped) control cables from the throttle
body (Fig. 12).
(5) Remove the three bolts that fasten the control
cable bracket to the intake manifold.
(6) Remove control cables from cylinder head cover
clip.
(7) Position control cables and bracket away from
cylinder head cover secure with tie straps.
(8) Remove the engine cylinder head cover mount-
ing bolts.
(9) Remove the engine cylinder head cover and
gasket.
Fig. 11 Cylinder Head Cover
9 - 22 ENGINE - 4.0LWJ
CYLINDER HEAD (Continued)

(10) Place a piece of wood (2 x 2) between the jack
stand and the engine vibration damper.
(11) Remove the engine mount through bolts.
(12) Using the jack stand, raise the engine until
adequate clearance is obtained to remove the oil pan.
(13) Remove transmission oil cooling lines (if
equipped) and oxygen sensor wiring supports that
are attached to the oil pan studs.
(14) Remove the oil pan bolts and studs. Carefully
slide the oil pan and gasket to the rear. If equipped
with an oil level sensor, take care not to damage the
sensor.
INSTALLATION
(1) Clean the block and pan gasket surfaces.
(2) Fabricate 4 alignment dowels from 1 1/2 x 1/4
inch bolts. Cut the head off the bolts and cut a slot
into the top of the dowel. This will allow easier
installation and removal with a screwdriver (Fig. 78).
(3) Install two dowels in the timing case cover.
Install the other two dowels in the cylinder block
(Fig. 79).
(4) Apply MopartSilicone Rubber Adhesive Seal-
ant on cylinder block to rear main bearing cap cor-
ners and cylinder block to front cover joints (four
places) (Fig. 80).
(5) Slide the one-piece gasket over the dowels and
onto the block and timing case cover.
(6) Position the oil pan over the dowels and onto
the gasket. If equipped with an oil level sensor, take
care not to damage the sensor.
(7) Install the 1/4 inch oil pan bolts. Tighten these
bolts to 9.5 N´m (84 in. lbs.) torque. Install the 5/16
inch oil pan bolts (Fig. 81). Tighten these bolts to 15
N´m (132 in. lbs.) torque.
(8) Remove the dowels. Install the remaining 1/4
inch oil pan bolts. Tighten these bolts to 9.5 N´m (84
in. lbs.) torque.
Fig. 78 Fabrication of Alignment Dowels
1 - 1/488ý 1 1/288BOLT
2 - DOWEL
3 - SLOT
Fig. 79 Position of Dowels in Cylinder Block
1 - DOWEL HOLES
2 - CYLINDER BLOCK
3 - 5/1688HOLES
4 - 5/1688HOLES
Fig. 80 Oil Pan Sealer Location
1 - SEALER LOCATIONS
Fig. 81 Position of 5/16 inch Oil Pan Bolts
1 - OIL PAN
2 - OIL PAN DRAIN PLUG
WJENGINE - 4.0L 9 - 55
OIL PAN (Continued)

(9) Lower the engine until it is properly located on
the engine mounts.
(10) Install the through bolts and tighten the nuts.
(11) Lower the jack stand and remove the piece of
wood.
(12) Install the engine flywheel and transmission
torque converter housing access cover.
(13) Install the engine starter motor. (Refer to 8 -
ELECTRICAL/STARTING/STARTER MOTOR -
INSTALLATION).
(14) Connect the exhaust pipe to the hanger and to
the engine exhaust manifold.
(15) Install transmission oil cooling lines (if
equipped) and oxygen sensor wiring supports that
attach to the oil pan studs.
(16) Install the oil pan drain plug (Fig. 81).
Tighten the plug to 34 N´m (25 ft. lbs.) torque.
(17) Lower the vehicle.
(18) Connect negative cable to battery.
(19) Fill the oil pan with engine oil to the specified
level.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR FAN. DO
NOT WEAR LOOSE CLOTHING.
(20) Start the engine and inspect for leaks.
ENGINE OIL PRESSURE
SENSOR
DESCRIPTION
The 3±wire, solid-state engine oil pressure sensor
(sending unit) is located in an engine oil pressure
gallery.
OPERATION
The oil pressure sensor uses three circuits. They
are:
²A 5±volt power supply from the Powertrain Con-
trol Module (PCM)
²A sensor ground through the PCM's sensor
return
²A signal to the PCM relating to engine oil pres-
sure
The oil pressure sensor has a 3±wire electrical
function very much like the Manifold Absolute Pres-
sure (MAP) sensor. Meaning different pressures
relate to different output voltages.
A 5±volt supply is sent to the sensor from the PCM
to power up the sensor. The sensor returns a voltage
signal back to the PCM relating to engine oil pres-
sure. This signal is then transferred (bussed) to theinstrument panel on either a CCD or PCI bus circuit
(depending on vehicle line) to operate the oil pressure
gauge and the check gauges lamp. Ground for the
sensor is provided by the PCM through a low-noise
sensor return.
OIL PUMP
REMOVAL
A gear-type oil pump is mounted at the underside
of the cylinder block opposite the No.4 main bearing.
(1) Drain the engine oil.
(2) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(3) Remove the pump-to-cylinder block attaching
bolts. Remove the pump assembly with gasket (Fig.
82).
CAUTION: If the oil pump is not to be serviced, DO
NOT disturb position of oil inlet tube and strainer
assembly in pump body. If the tube is moved within
the pump body, a replacement tube and strainer
assembly must be installed to assure an airtight
seal.
Fig. 82 Oil Pump Assembly
1 - OIL FILTER ADAPTOR
2 - BLOCK
3 - GASKET
4 - OIL INLET TUBE
5 - OIL PUMP
6 - STRAINER ASSEMBLY
7 - ATTACHING BOLTS
9 - 56 ENGINE - 4.0LWJ
OIL PAN (Continued)