fuel pressure JEEP XJ 1995 Service And Owner's Guide

MALFUNCTION INDICATOR (CHECK ENGINE)
LAMP
The Powertrain Control Module (PCM) provides
ground for the malfunction indicator (Check Engine)
lamp on circuit G3. Circuit G3 connects to cavity 32
of the PCM. Circuit G5 connects to the instrument
cluster and supplies battery voltage for the malfunc-
tion indicator lamp. When illuminated, the malfunc-
tion indicator lamp displays the message CHECK
ENGINE.
For information regarding diagnostic trouble code
access using the malfunction indicator lamp, refer to
Group 14, Fuel Systems.
UP-SHIFT LAMP
On vehicles equipped with a manual transmission,
the Powertrain Control Module (PCM) provides
ground for the Up-Shift lamp on circuit K54. Circuit
G5 provides battery voltage for the lamp.
ABS WARNING LAMP
Circuit G5 provides power for the ABS warning
lamp at the instrument cluster. Ground for the ABS
warning lamp is provided by either the ABS control
module or by the ABS power relay when the relay is
not energized. The ABS control module illuminates
the lamp by providing ground on circuit G19.
Circuit G19 splices to connect to circuit B15
through a diode. When the ABS power relay is not
energized, it connects circuit B15 to circuit Z12. The
ground path for the warning lamp is provided
through the diode to circuit B15, through the ABS
power relay to ground on circuit Z12.
The diode between circuit G19 and B15 prevents
voltage from flowing to the ABS control module when
the ABS power relay switches to supply power on cir-
cuit B15.
BRAKE WARNING LAMP
Circuit G5 provides battery voltage for the brake
warning lamp. Circuit G11 can provide ground for
the lamp in 3 ways. The first ground path is through
the ignition switch when the key is in the START po-
sition.
The second ground path for the brake warning
lamp on circuit G11 is through the case grounded
brake warning switch. When the switch closes it pro-
vides a ground.
The third ground path on circuit G11 is through
the case grounded park brake switch. When the
switch closes it provides ground.
HIGH BEAM INDICATOR LAMP
Circuit G34 supplies power for the high-beam indi-
cator lamp when the operator either flashes the opti-
cal horn (high beams) or selects high beam operation.
Circuit Z1 provides the ground path for the lamp.
Circuit L3 from the headlamp switch powers the
high beam circuits of the headlamps. On vehicles not
equipped with Daytime Running Lamps (DRL), cir-
cuit G34 double crimps to circuit L3 at the bulkhead
connector.
On vehicles equipped with DRL, circuit L3 splices
to the DRL module. The DRL module powers circuit
G34.
TURN SIGNAL INDICATOR LAMPS
Circuit L61 supplies battery voltage to the left turn
signal indicator lamp. The right turn signal indicator
lamp receives battery voltage from circuit L60. The
turn signal/hazard flasher switch powers circuits L60
and L61. Circuit Z1 provides ground for the lamps.
HELPFUL INFORMATION
²If the warning lamps, gauges and indicator lamps
don't operate, check fuse 4 in the PDC and fuse 9 in
the fuse block.
²If the illumination lamps don't operate, check fuse
10 in the fuse block.
DIAGRAM INDEX
Component Page
4WD Switch............................8W-40-9
ABS Control Module......................8W-40-5
Brake Warning Switch.....................8W-40-5
Combination Buzzer.....................8W-40-7, 8
Daytime Running Lamp (DRL) Module.........8W-40-4, 6
Engine Coolant Temperature Sensor...........8W-40-7, 8
Engine Oil Pressure Sensor..................8W-40-9
Fuse 3 (PDC).......................8W-40-3, 7, 8
Fuse 4 (PDC).......................8W-40-4, 7, 8
Fuse 7 (PDC)...........................8W-40-6
Fuse 8 (Fuse Block)...................8W-40-3, 7, 8
Fuse 9 (Fuse Block).......................8W-40-8
Fuse 10 (Fuse Block).................8W-40-3, 7, 10
Gauge Package......................8W-40-7, 8, 9
Headlamp Switch...................8W-40-3, 6, 7, 8
Headlamp Dimmer Switch...................8W-40-6
Ignition Switch......................8W-40-4, 5, 8
Instrument Cluster...................8W-40-3 thru 9
Panel Lamp Dimmer Switch..............8W-40-3, 7, 8
Park Brake Switch........................8W-40-5
Powertrain Control Module.................8W-40-4, 5
8W - 40 - 2 8W-40 INSTRUMENT CLUSTERÐYJ VEHICLESJ

minutes). The use of a locating dowel is recom-
mended during assembly to prevent smearing the
material off location.
Mopar Gasket Maker should be applied sparingly
to one gasket surface. The sealant diameter should
be 1.00 mm (0.04 inch) or less. Be certain the mate-
rial surrounds each mounting hole. Excess material
can easily be wiped off. Components should be
torqued in place within 15 minutes. The use of a lo-
cating dowel is recommended during assembly to pre-
vent smearing the material off location.
ENGINE PERFORMANCE
To provide best vehicle performance and lowest ve-
hicle emissions, it is most important that the tune-up
be done accurately. Use the specifications listed on
the Vehicle Emission Control Information label found
on the engine compartment hood.
(1) Test battery specific gravity. Add water, if nec-
essary. Clean and tighten battery connections.
(2) Test cranking amperage draw (refer to Group
8B, Battery/Starter Service for the proper proce-
dures).
(3) Tighten the intake manifold bolts (refer to
Group 11, Exhaust System and Intake Manifold for
the proper specifications).
(4) Perform cylinder compression test:
(a) Check engine oil level and add oil, if neces-
sary.
(b) Drive the vehicle until engine reaches normal
operating temperature.
(c) Select a route free from traffic and other
forms of congestion, observe all traffic laws and
briskly accelerate through the gears several times.
The higher engine speed may help clean out valve
seat deposits which can prevent accurate compres-
sion readings.
CAUTION: DO NOT overspeed the engine.
(d) Remove all spark plugs from engine. As spark
plugs are being removed, check electrodes for ab-
normal firing indicatorsÐfouled, hot, oily, etc.
Record cylinder number of spark plug for future
reference.
(e) Disconnect coil wire from distributor and se-
cure to good ground to prevent a spark from start-
ing a fire.
(f) Be sure throttle blades are fully open during
the compression check.
(g) Insert compression gage adaptor into the
No.1 spark plug hole. Crank engine until maximum
pressure is reached on gauge. Record this pressure
as No.1 cylinder pressure.
(h) Repeat Step 4g for all remaining cylinders.
(i) Compression should not be less than 689 kPa
(100 psi) and not vary more than 172 kPa (25 psi)
from cylinder to cylinder.(j) If cylinder(s) have abnormally low compres-
sion pressures, repeat steps 4a through 4h.
(k) If the same cylinder(s) repeat an abnormally
low reading, it could indicate the existence of a
problem in the cylinder.
The recommended compression pressures are
to be used only as a guide to diagnosing engine
problems. An engine should NOT be disassem-
bled to determine the cause of low compression
unless some malfunction is present.
(5) Clean or replace spark plugs as necessary. Ad-
just gap (refer to Group 8D, Ignition System for gap
adjustment and torque).
(6) Test resistance of spark plug cables (refer to
Group 8D, Ignition System).
(7) Inspect the primary wire. Test coil output volt-
age, primary and secondary resistance. Replace parts
as necessary (refer to Group 8D, Ignition System and
make necessary adjustment).
(8) Perform a combustion analysis.
(9) Test fuel pump for pressure (refer to Group 14,
Fuel System for the proper specifications).
(10) Inspect air filter element (refer to Group 0,
Lubrication and Maintenance for the proper proce-
dure).
(11) Inspect crankcase ventilation system (refer to
Group 0, Lubrication and Maintenance for the proper
procedure).
(12) For emission controls refer to Group 25, Emis-
sion Controls System for service procedures.
(13) Inspect and adjust accessory belt drives (refer
to Group 7, Cooling System for the proper adjust-
ments).
(14) Road test vehicle as a final test.
HONING CYLINDER BORES
Before honing, stuff plenty of clean shop towels un-
der the bores and over the crankshaft to keep abra-
sive materials from entering the crankshaft area.
(1) Used carefully, the Cylinder Bore Sizing Hone
C-823 equipped with 220 grit stones, is the best tool
for this job. In addition to deglazing, it will reduce
taper and out-of-round as well as removing light
scuffing, scoring or scratches. Usually a few strokes
will clean up a bore and maintain the required lim-
its.
CAUTION: DO NOT use rigid type hones to remove
cylinder wall glaze.
(2) Deglazing of the cylinder walls may be done if
the cylinder bore is straight and round. Use a cylin-
der surfacing hone, Honing Tool C-3501, equipped
with 280 grit stones (C-3501-3810). 20-60 strokes, de-
pending on the bore condition, will be sufficient to
provide a satisfactory surface. Using honing oil
C-3501-3880 or a light honing oil available from ma-
jor oil distributors.
9 - 2 ENGINESJ

CONNECTING ROD BEARING CLEARANCE
Engine connecting rod bearing clearances can be
determined by use of Plastigage, or equivalent. The
following is the recommended procedures for the use
of Plastigage:
(1) Remove oil film from surface to be checked.
Plastigage is soluble in oil.
(2) Place a piece of Plastigage across the entire width
of the bearing cap shell (Fig. 2). Position the Plastigage
approximately 6.35 mm (1/4 inch) off center and away
from the oil holes. In addition, suspect areas can be
checked by placing the Plastigage in the suspect area.
(3) The crankshaft must be turned until the connect-
ing rod to be checked starts moving toward the top of
the engine. Only then should the rod cap with Plasti-
gage in place be assembled. Tighten the rod cap nut to
45 Nzm (33 ft. lbs.) torque.DO NOT rotate the crank-
shaft or the Plastigage may be smeared, giving in-
accurate results.
(4) Remove the bearing cap and compare the width
of the flattened Plastigage with the scale provided on
the package (Fig. 3). Plastigage generally comes in 2
scales (one scale is in inches and the other is a met-
ric scale). Locate the band closest to the same width.
This band shows the amount of clearance. Differ-
ences in readings between the ends indicate the
amount of taper present. Record all readings taken
(refer to Engine Specifications).
(5) Plastigage is available in a variety of clearance
ranges. The 0.025-0.076 mm (0.001-0.003 inch) range
is usually the most appropriate for checking engine
bearing clearances.
REPAIR DAMAGED OR WORN THREADS
Damaged or worn threads can be repaired. Essen-
tially, this repair consists of:
²Drilling out worn or damaged threads.
²Tapping the hole with a special Heli-Coil Tap, or
equivalent.
²Installing an insert into the tapped hole.
This brings the hole back to its original thread
size.
CAUTION: Be sure that the tapped holes maintain
the original center line.Heli-Coil tools and inserts are readily available
from automotive parts jobbers.
SERVICE ENGINE ASSEMBLY (SHORT BLOCK)
A service replacement engine assembly (short
block) may be installed whenever the original cylin-
der block is defective or damaged beyond repair. It
consists of the cylinder block, crankshaft, piston and
rod assemblies. If needed, the camshaft must be pro-
cured separately and installed before the engine is
installed in the vehicle.
A short block is identified with the letter ``S'' stamped
on the same machined surface where the build date
code is stamped for complete engine assemblies.
Installation includes the transfer of components
from the defective or damaged original engine. Fol-
low the appropriate procedures for cleaning, inspec-
tion and torque tightening.
HYDROSTATIC LOCK
When an engine is suspected of hydrostatic lock
(regardless of what caused the problem), follow the
steps below.
(1) Perform the Fuel Pressure Release Procedure
(refer to Group 14, Fuel System).
(2) Disconnect the negative cable from the battery.
(3) Inspect air cleaner, induction system and in-
take manifold to ensure system is dry and clear of
foreign material.
(4) Place a shop towel around the spark plugs to
catch any fluid that may possibly be under pressure in
the cylinder head. Remove the plugs from the engine.
CAUTION: DO NOT use the starter motor to rotate
the crankshaft. Severe damage could occur.
(5) With all spark plugs removed, rotate the crank-
shaft using a breaker bar and socket.
(6) Identify the fluid in the cylinders (i.e. coolant,
fuel, oil, etc.).
(7) Make sure all fluid has been removed from the
cylinders.
(8) Repair engine or components as necessary to
prevent this problem from occurring again.
(9) Squirt engine oil into the cylinders to lubricate
the walls. This will prevent damage on restart.
(10) Install new spark plugs. Tighten the spark
plugs to 37 Nzm (27 ft. lbs.) torque.
(11) Drain engine oil. Remove and discard the oil
filter.
(12) Install the drain plug. Tighten the plug to 34
Nzm (25 ft. lbs.) torque.
(13) Install a new oil filter.
(14) Fill engine crankcase with the specified
amount and grade of oil (refer to Group 0, Lubrica-
tion and Maintenance).
(15) Connect the negative cable to the battery.
(16) Start the engine and check for any leaks.
Fig. 3 Clearance Measurement
9 - 4 ENGINESJ

ENGINE DIAGNOSIS
Engine diagnosis is helpful in determining the
causes of malfunctions not detected and remedied by
routine tune-ups.
These malfunctions may be classified as either per-
formance (e.g., engine idles rough and stalls) or me-
chanical (e.g., a strange noise).
Refer to the Service DiagnosisÐPerformance chart
and the Service DiagnosisÐMechanical chart for pos-
sible causes and corrections of malfunctions. Refer to
Group 14, Fuel System for the fuel system diagnosis.
GENERAL INFORMATION
Additional tests and diagnostic procedures may be
necessary for specific engine malfunctions that can
not be isolated with the Service Diagnosis charts. In-
formation concerning additional tests and diagnosis
is provided within the following diagnosis:
²Cylinder Compression Pressure Test.
²Cylinder Combustion Pressure Leakage Test.
²Engine Cylinder Head Gasket Failure Diagnosis.
²Intake Manifold Leakage Diagnosis.
INTAKE MANIFOLD LEAKAGE DIAGNOSIS
An intake manifold air leak is characterized by
lower than normal manifold vacuum. Also, one or
more cylinders may not be functioning.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A DI-
RECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR THE FAN.
DO NOT WEAR LOOSE CLOTHING.
METHOD 1
(1) Start the engine.
(2) Spray a small stream of water at the suspected
leak area.
(3) If a change in RPM'S, the area of the suspected
leak has been found.
(4) Repair as required.
CYLINDER COMPRESSION PRESSURE TEST
The results of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise the indicated compression pressures may
not be valid for diagnosis purposes.
(1) Clean the spark plug recesses with compressed
air.
(2) Remove the spark plugs.
(3) Secure the throttle in the wide-open position.
(4) Disconnect the ignition coil.(5) Insert a compression pressure gauge and rotate
the engine with the engine starter motor for three
revolutions.
(6) Record the compression pressure on the 3rd
revolution. Continue the test for the remaining cylin-
ders.
Refer to Engine Specifications for the correct en-
gine compression pressures.
ENGINE CYLINDER HEAD GASKET FAILURE
DIAGNOSIS
A leaking engine cylinder head gasket usually re-
sults in loss of power, loss of coolant and engine mis-
firing.
An engine cylinder head gasket leak can be located
between adjacent cylinders or between a cylinder and
the adjacent water jacket.
²An engine cylinder head gasket leaking between
adjacent cylinders is indicated by a loss of power
and/or engine misfire.
²An engine cylinder head gasket leaking between a
cylinder and an adjacent water jacket is indicated by
coolant foaming or overheating and loss of coolant.
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders; follow the proce-
dures outlined in Cylinder Compression Pressure
Test. An engine cylinder head gasket leaking between
adjacent cylinders will result in approximately a 50-
70% reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE
TEST
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A DI-
RECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR THE FAN.
DO NOT WEAR LOOSE CLOTHING.
Remove the radiator cap.
Start the engine and allow it to warm up until the
engine thermostat opens.
If a large combustion/compression pressure leak ex-
ists, bubbles will be visible in the coolant.
If bubbles are not visible, install a radiator pres-
sure tester and pressurize the coolant system.
If a cylinder is leaking combustion pressure into
the water jacket, the tester pointer will pulsate with
every combustion stroke of the cylinder.
JENGINES 9 - 5

(2) Install the upper inner retainer and bushing on
the top of the damper.
(3) Position the upper damper bracket over the
damper and install the stud nut and bolts.
(4) Tighten the stud nut to 23 Nzm (17 ft. lbs.)
torque. Tighten the bracket bolts to 61 Nzm (45 ft.
lbs.) torque.
(5) Install the bushing, upper outer retainer and
damper nut.
(6) Install the bushing, lower outer retainer and
damper nut.
(7) Tighten the upper and lower damper nuts.
(8) Connect negative cable to battery.
ENGINE ASSEMBLYÐXJ VEHICLES
REMOVAL
(1) Disconnect the battery cables. Remove the bat-
tery.
(2) Mark the hinge locations on the hood panel for
alignment reference during installation. Remove the
engine compartment lamp. Remove the hood.
WARNING: THE COOLANT IN A RECENTLY OPER-
ATED ENGINE IS HOT AND PRESSURIZED. USE
CARE TO PREVENT SCALDING BY HOT COOLANT.
CAREFULLY RELEASE THE PRESSURE BEFORE
REMOVING THE RADIATOR DRAIN COCK AND CAP.(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 lower radiator hose.
(5) Remove the upper radiator hose and coolant re-
covery hose (Fig. 15).
(6) Remove the fan shroud (Fig. 15).
(7) Disconnect the transmission fluid cooler tubing
(automatic transmission).
(8) Remove the radiator/condenser (if equipped
with air conditioning).
(9) Remove fan assembly and install a 5/16 x 1/2-
inch SAE capscrew through fan pulley into water
pump flange. This will maintain the pulley and wa-
ter pump in alignment when crankshaft is rotated.
(10) Disconnect the heater hoses (Figs. 16 and 17).
(11) Disconnect the throttle linkages (Fig. 16),
speed control cable (if equipped) and throttle valve
rod.
(12) Disconnect the oxygen sensor wire connector.
(13) Disconnect the wires from the starter motor
solenoid.
(14) Disconnect all fuel injection harness connec-
tions.
(15) Disconnect the quick-connect fuel lines at the
fuel rail and return line by squeezing the two retain-
ing tabs against the fuel tube (Fig. 16). Pull the fuel
tube and retainer from the quick-connect fitting (re-
fer to Group 14, Fuel System for the proper proce-
dure).
(16) Remove the fuel line bracket from the intake
manifold.
(17) Remove the air cleaner assembly (Fig. 18).
(18) If equipped with air conditioning, remove the
service valves and cap the compressor ports.
(19) Remove the power brake vacuum check valve
from the booster, if equipped.
(20) If equipped with power steering (Fig. 18):
Fig. 14 Engine Damper
Fig. 15 Upper Radiator Hose, Coolant Recovery
Hose & Fan Shroud
9 - 18 2.5L ENGINEJ

(a) Align the transmission torque converter hous-
ing with the engine.
(b) Loosely install the converter housing lower
bolts and install the next higher bolt and nut on
each side.
(c) Tighten all 4 bolts finger-tight.
(5) Install the engine support cushions (if re-
moved).
(6) Lower the engine and engine support cushions
onto the engine compartment brackets.
(7) Remove the engine lifting device.
(8) Raise the vehicle.
(9) If equipped with an automatic transmission:
(a) Install the converter-to-drive plate bolts. En-
sure the installation reference marks are aligned.
Tighten the bolts to 54 Nzm (40 ft. lbs.) torque.
(b) Install the converter-housing access cover.
(c) Install the exhaust pipe support.
(10) Install the remaining converter or flywheel
housing bolts.
(11) Install the starter motor and connect the ca-
ble. Tighten the bolts to 45 Nzm (33 ft. lbs.) torque.
(12) Tighten the engine support cushing through-
bolt nuts.
(13) Install the remaining flywheel and converter
housing bolts. Tighten the bolts to 38 Nzm (28 ft. lbs.)
torque.
(14) Connect the exhaust pipe to the manifold.
(15) Install the oil filter.
(16) Lower the vehicle.
(17) Connect the coolant hoses and tighten the
clamps.
(18) If equipped with power steering:
(a) Remove the protective caps
(b) Connect the hoses to the fittings at the steer-
ing gear. Tighten the nut to 52 Nzm (38 ft. lbs.)
torque.
(c) Fill the pump reservoir with fluid.
(19) Remove the pulley-to-water pump flange
alignment capscrew and install the fan and spacer or
Tempatrol fan assembly.
(20) Install the fan shroud and radiator and con-
denser (if equipped with air conditioning).
(21) Connect the radiator hoses.
(22) Connect the automatic transmission fluid
cooler pipes, if equipped.
(23) Connect the oxygen sensor wire connector.
(24) Connect the throttle valve rod and retainer.
Connect the throttle cable and install the rod. Install
the throttle valve rod spring.
(25) Connect the speed control cable, if equipped.
(26) Connect the fuel supply and return lines to
the throttle body.
(27) Connect all the vacuum hoses and wire con-
nectors.
(28) Connect the service valves to the A/C compres-
sor ports, if equipped with air conditioning.(29) Fill the power steering reservoir.
(30) Connect the battery cables.
(31) Install the hood.
(32) Install the air cleaner.
(33) Start the engine and inspect for leaks.
(34) Fill the cooling system.
(35) Stop the engine and check the fluid levels.
Add fluid, as required.
ENGINE ASSEMBLYÐYJ VEHICLES
REMOVAL
(1) Place a protective cloth over the windshield
frame. Raise the hood and rest it on the windshield
frame (Fig. 19).
(2) Disconnect the battery cable clamps and re-
move the battery.
WARNING: THE COOLANT IN A RECENTLY OPER-
ATED ENGINE IS HOT AND PRESSURIZED. USE
CARE TO PREVENT SCALDING BY HOT COOLANT.
CAREFULLY RELEASE THE PRESSURE BEFORE
REMOVING THE RADIATOR DRAIN COCK AND CAP.
(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) Disconnect the wire connectors from the gener-
ator.
(5) Disconnect the ignition coil and distributor wire
connectors.
(6) Disconnect the oil pressure sender wire connec-
tor.
Fig. 19 Hood on Windshield Frame
9 - 20 2.5L ENGINEJ

(6) Remove upper radiator support retaining bolts
and remove radiator support.
(7) Remove the fan shroud (Fig. 13) and electric
cooling fan.
(8) Disconnect the transmission fluid cooler tubing
(automatic transmission).
(9) Disconnect radiator fan switch wire connector.
(10)Vehicles with Air Conditioning:
(a) Discharge the A/C condenser.
(b) Remove the service valves and cap the com-
pressor ports.
(11) Remove the radiator or radiator and con-
denser (if equipped with A/C).
(12) Remove the fan assembly from the idler pul-
ley.
(13) Disconnect the heater hoses at the engine
thermostat housing and water pump (Figs. 13 and
14).
(14) Disconnect the throttle linkages (Fig. 15).
(15) Disconnect the speed control cable (if
equipped)Ð(Fig. 15).(16) Disconnect the line pressure cable (if equipped
with automatic transmission).
(17) Disconnect injection system wire harness con-
nector at the dash panel.
(18) Disconnect the distributor electrical connec-
tion and the oil pressure switch connector.
(19) Perform the Fuel System Pressure Release
procedure (refer to Group 14, Fuel System).
(20) Disconnect the quick-connect fuel lines at the
fuel rail and return line by squeezing the two retain-
ing tabs against the fuel tube (Fig. 15). Pull the fuel
tube and retainer from the quick-connect fitting (re-
fer to Group 14, Fuel System for the proper proce-
dure).
(21) Remove the fuel line bracket from the intake
manifold.
(22) Remove the air cleaner assembly (Fig. 16).
(23) Remove the power brake vacuum check valve
from the booster, if equipped.
(24) If equipped with power steering (Fig. 16):
(a) Disconnect the hoses from the fittings at the
steering gear.
(b) Drain the pump reservoir.
(c) Cap the fittings on the hoses and steering
gear to prevent foreign objects from entering the
system.
(25) Identify, tag and disconnect all necessary wire
connectors and vacuum hoses.
(26) Raise and support the vehicle.
(27) Disconnect the wires from the starter motor
solenoid.
(28) Remove the starter motor.
Fig. 13 Upper Radiator Hose, Coolant Recovery
Hose, Fan Shroud & Heater hoses
Fig. 14 Heater Hoses (RH Drive Vehicle)
Fig. 15 Accelerator Cable, Speed Control Cable,
Automatic Transmission Control Cable & Quick-
Connect Fuel Lines
9 - 60 4.0L ENGINEJ

(29) Disconnect the exhaust pipe from the mani-
fold.
(30) Disconnect the engine speed sensor wire con-
nection.
(31) Remove the exhaust pipe support.
(32) Remove the flywheel and converter housing
access cover.
(33)Vehicles with Automatic Transmission:
(a) Mark the converter and drive plate location.
(b) Remove the converter-to-drive plate bolts.
(34) Remove the upper flywheel and converter
housing bolts and loosen the bottom bolts.
(35) Remove the engine mount cushion-to-engine
compartment bracket bolts.
(36) Lower the vehicle.
(37) Attach a lifting device to the engine.
(38) Raise the engine off the front supports.
(39) Place a support or floor jack under the con-
verter (or flywheel) housing.
(40) Remove the remaining converter (or flywheel)
housing bolts.
(41) Lift the engine out of the engine compart-
ment.
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 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 en-
gine mount cushions from the engine mount bracket
as an aide in alignment of the engine to the trans-
mission.
(2)Vehicles with Manual Transmission:
(a) Insert the transmission shaft into the clutch
spline.
(b) Align the flywheel housing with the engine.(c) Install and tighten the flywheel housing lower
bolts finger tight.
(3)Vehicles with Automatic Transmission:
(a) Align the transmission torque converter hous-
ing with the engine.
(b) Loosely install the converter housing lower
bolts and install the next higher bolt and nut on
each side.
(c) Tighten all 4 bolts finger tight.
(4) Install the engine mount cushions (if removed).
(5) Lower the engine and engine mount cushions
onto the engine compartment brackets. Install the
bolts and finger tighten the nuts.
(6) Remove the engine lifting device.
(7) Raise and support the vehicle.
(8) Install the remaining flywheel and converter
housing bolts. Tighten all bolts to 38 Nzm (28 ft. lbs.)
torque.
(9)Vehicles with Automatic Transmission:
(a) Install the converter-to-drive plate bolts.
(b) Ensure the installation reference marks are
aligned.
(10) Install the flywheel and converter housing ac-
cess cover.
(11) Install the exhaust pipe support and tighten
the screw.
(12) Tighten the engine mount-to-bracket bolts.
(13) Connect the engine speed sensor wire connec-
tions and tighten the screws.
(14) Connect the exhaust pipe to the manifold.
(15) Install the starter motor and connect the ca-
ble.
(16) Connect the wires to the starter motor sole-
noid.
(17) Lower the vehicle.
(18) Connect all the vacuum hoses and wire con-
nectors identified during engine removal.
(19) If equipped with power steering:
(a) Remove the protective caps
(b) Connect the hoses to the fittings at the steer-
ing gear. Tighten the nut to 52 Nzm (38 ft. lbs.)
torque.
(c) Fill the pump reservoir with fluid.
(20) Install the power brake vacuum check valve to
the booster, if equipped.
(21) Connect the fuel inlet and return hoses at the
fuel rail. Verify that the quick-connect fitting assem-
bly fits securely over the fuel lines by giving the fuel
lines a firm tug.
(22) Install the fuel line bracket to the intake man-
ifold.
(23) Connect the distributor electrical connector
and oil pressure switch connector.
(24) Connect the injection system wire harness
connector on the dash panel.
(25) Connect the line pressure cable (if equipped
with automatic transmission).
Fig. 16 Air Cleaner Assembly & Power Steering
Pump
J4.0L ENGINE 9 - 61

(26) Connect the speed control cable, if equipped.
(27) Connect the throttle cable linkages.
(28) Connect the heater hoses at the engine ther-
mostat housing and water pump.
(29) Install the fan assembly to the idler pulley.
(30) Install the radiator or radiator and condenser
(if equipped with A/C).
(31) Connect the service valves to the A/C compres-
sor ports, if equipped with A/C.
(32) Charge the air conditioner system.
(33) Connect radiator fan switch wire.
(34) Connect automatic transmission fluid cooler
lines, if equipped.
(35) Install the fan shroud, electric cooling fan and
radiator and condenser (if equipped with A/C).
(36) Install upper radiator support.
(37) Connect the upper radiator hose.
(38) Connect the lower radiator hose.
(39) Fill the cooling system with reusable coolant
and/or new coolant.
(40) Align the hood to the scribe marks. Install the
hood.
(41) Connect the vacuum harness connector.
(a) Firmly push the connectors together ensuring
that the retaining tabs are engaged.
(b) Insert the vacuum connector assembly into
the retaining bracket on the intake manifold.
(42) Install the air cleaner assembly.
(43) Install the battery and connect the battery ca-
ble.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A DI-
RECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR FAN. DO
NOT WEAR LOOSE CLOTHING.
(44) Start the engine, inspect for leaks and correct
the fluid levels, as necessary.
ENGINE ASSEMBLYÐYJ VEHICLES
REMOVAL
(1) Place a protective cloth over the windshield
frame. Raise the hood and rest it on the windshield
frame (Fig. 17).
(2) Disconnect the battery cables. Remove the bat-
tery.
WARNING: THE COOLANT IN A RECENTLY OPERATED
ENGINE IS HOT AND PRESSURIZED. USE CARE TO
PREVENT SCALDING BY HOT COOLANT. CAREFULLY
RELEASE THE PRESSURE BEFORE REMOVING THE
RADIATOR DRAIN COCK AND CAP.
(3) Remove the radiator drain cock and radiator
cap to drain the coolant. DO NOT waste reusablecoolant. If the solution is clean, drain the coolant into
a clean container for reuse.
(4) Disconnect the wire connectors from the gener-
ator.
(5) Disconnect the ignition coil and distributor wire
connectors.
(6) Disconnect the oil pressure sender wire connec-
tor.
(7) Disconnect the wires at the starter motor sole-
noid and injection wire harness connector.
(8) Perform the Fuel System Pressure Release pro-
cedure (refer to Group 14, Fuel System).
(9) Disconnect the quick-connect fuel lines at the
fuel rail and return line by squeezing the retaining
tabs against the fuel tube (Fig. 18). Pull the fuel tube
and retainer from the quick-connect fitting (refer to
Group 14, Fuel System for the proper procedure).
(10) Remove the fuel line bracket from the intake
manifold.
(11) Disconnect the engine ground strap.
(12) Remove the air cleaner (Fig. 18).
(13) Disconnect the vacuum purge hose at the fuel
vapor canister tee.
(14) Disconnect the idle speed actuator wire con-
nector.
(15) Disconnect the throttle cable and remove it
from the bracket (Fig. 18).
(16) Disconnect the throttle rod at the bellcrank.
(17) Disconnect the speed control cable, if equipped
(Fig. 18).
Fig. 17 Hood on Windshield Frame
9 - 62 4.0L ENGINEJ

(9) If equipped, disconnect the power steering
pump bracket. Set the pump and bracket aside. DO
NOT disconnect the hoses.
(10) Perform the Fuel System Pressure Release
procedure (refer to Group 14, Fuel System).
(11) Remove the fuel lines and vacuum advance
hose.
(12) Remove the intake and engine exhaust mani-
folds from the engine cylinder head (refer to Group
11, Exhaust System and Intake Manifold for the
proper procedures).
(13) Disconnect the ignition wires and remove the
spark plugs.
(14) Disconnect the temperature sending unit wire
connector.
(15) Remove the ignition coil and bracket assem-
bly.
(16) Remove the engine cylinder head bolts. Bolt
No.14 cannot be removed until the head is moved for-
ward (Fig. 6). Pull bolt No.14 out as far as it will go
and then suspend the bolt in this position (tape
around the bolt).
(17) Remove the engine cylinder head and gasket
(Fig. 6).
(18) If this was the first time the bolts were re-
moved, put a paint dab on the top of the bolt. If the
bolts have a paint dab on the top of the bolt or it
isn't known if they were used before, discard the
bolts.
(19) Stuff clean lint free shop towels into the cylin-
der bores.
CLEANING
Thoroughly clean the engine cylinder head and cyl-
inder block mating surfaces. Clean the intake and
engine exhaust manifold and engine cylinder head
mating surfaces. Remove all gasket material and car-
bon.
Check to ensure that no coolant or foreign material
has fallen into the tappet bore area.Remove the carbon deposits from the combustion
chambers and top of the pistons.
INSPECTION
Use a straightedge and feeler gauge to check the
flatness of the engine cylinder head and block mating
surfaces.
INSTALLATION
The engine cylinder head gasket is a composition
gasket. The gasket is to be installed DRY.DO NOT
use a gasket sealing compound on the gasket.
If the engine cylinder head is to be replaced and
the original valves used, measure the valve stem di-
ameter. Only standard size valves can be used with a
service replacement engine cylinder head unless the
replacement head valve stem guide bores are reamed
to accommodate oversize valve stems. Remove all
carbon buildup and reface the valves.
(1) Remove the shop towels from the cylinder
bores. Coat the bores with clean engine oil.
(2) Position the engine cylinder head gasket (with
the numbers facing up) onto the cylinder block.
CAUTION: Engine cylinder head bolts should be re-
used only once. Replace the head bolts if they were
used before or if they have a paint dab on the top
of the bolt.
(3) With bolt No.14 held in place (tape around
bolt), install the engine cylinder head. Remove the
tape from bolt No.14.
(4) Coat the threads of stud bolt No.11 with Loctite
592 sealant, or equivalent.
(5) Tighten the engine cylinder head bolts in se-
quence according to the following procedure (Fig. 7):
(a) Tighten all bolts in sequence (1 through 14)
to 30 Nzm (22 ft. lbs.) torque.
(b) Tighten all bolts in sequence (1 through 14)
to 61 Nzm (45 ft. lbs.) torque.
(c) Check all bolts to verify they are set to 61
Nzm (45 ft. lbs.) torque.
(d) Tighten bolts (in sequence):
²Bolts 1 through 10 to 149 Nzm (110 ft. lbs.) torque.
²Bolt 11 to 13 Nzm (100 ft. lbs.) torque.
²Bolts 12 through 14 to 149 Nzm (110 ft. lbs.)
torque.
CAUTION: During the final tightening sequence,
bolt No.11 will be tightened to a lower torque than
the rest of the bolts. DO NOT overtighten bolt
No.11.
(e) Check all bolts in sequence to verify the cor-
rect torque.
(f) If not already done, clean and mark each bolt
with a dab of paint after tightening. Should you en-
Fig. 6 Engine Cylinder Head Assembly
9 - 68 4.0L ENGINEJ