2002 JEEP LIBERTY coolant

(8) Install the starter.
(9) Connect the crankshaft position sensor.
(10) Install the engine block heater power cable, if
equipped.
CAUTION: The structural cover requires a specific
torque sequence. Failure to follow this sequence
may cause severe damage to the cover.
(11) Install the structural cover.
(12) Install the exhaust pipe.
(13) Connect the oxygen sensors.
(14) Lower vehicle.
(15) Connect the knock sensors.
(16) Connect the engine to body ground straps.
(17) Install the power brake booster vacuum hose.
(18) Install the breather hoses.
(19) Install the PCV hose.
(20) Install the fuel rail.
(21) Install the coil over plugs.
(22) Reconnect the engine wiring harness at the
following points:
²Intake air temperature (IAT) sensor
²Fuel Injectors
²Throttle Position (TPS) Switch
²Idle Air Control (IAC) Motor
²Engine Oil Pressure Switch
²Engine Coolant Temperature (ECT) Sensor
²Manifold Absolute Pressure MAP) Sensor
²Camshaft Position (CMP) Sensor
²Coil Over Plugs
²Crankshaft Position Sensor
(23) Connect lower radiator hose.
(24) Connect upper radiator hose.
(25) Connect throttle and speed control cables.
(26) Install the heater hose assembly.
(27) Install coolant recovery bottle.
(28) Install the power steering pump.
(29) Install the generator.
(30) Install the A/C compressor.
(31) Install the drive belt.
(32) Install the fan shroud with the electric fan
assembly.
(33) Install the radiator core support bracket.
(34) Install the air cleaner assembly.
(35) Refill the engine cooling system.
(36) Install the hood.
(37) Check and fill engine oil.
(38) Connect the battery negative cable.
(39) Start the engine and check for leaks.SPECIFICATIONS
SPECIFICATIONS - 2.4L ENGINE
DESCRIPTION SPECIFICATION
General Specification
Type In-Line OHV, DOHC
Number of Cylinders 4
Displacement 2.4 Liters
(148 cu. in.)
Bore 87.5 mm
(3.445 in.)
Stroke 101.0 mm
(3.976 in.)
Compression Ratio 9.4:1
Firing Order 1-3-4-2
Compression Pressure 690 kPa (Minimum)
(100 psi Minimum)
Max. Variation Between
Cylinders25%
Cylinder Block
Cylinder Bore Diameter 87.4924±87.5076 mm
(3.4446±3.4452 in.)
Out-of-Round (Max.) 0.051 mm
(0.002 in.)
Taper (Max.) 0.051 mm
(0.002 in.)
Pistons
Piston Diameter 87.463±87.481 mm
(3.4434±3.4441 in.)
Clearance @ 14 mm
(9/16 in.) from bottom of
skirt0.024±0.057 mm
(0.0009±0.0022 in.)
Weight 346±356 grams
(12.20±12.56 oz.)
Land Clearance
(Diametrical)0.614±0.664 mm
(0.024±0.026 in.)
Piston Length 66.25 mm
(2.608 in.)
Piston Ring Groove
Depth No. 14.640±4.784 mm
(0.182±0.188 in.)
Piston Ring Groove
Depth No. 24.575±4.719 mm
(0.180±0.185 in.)
KJENGINE9s-13
ENGINE - 2.4L (Continued)

Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
²Engine overheating
²Loss of coolant
²Excessive steam (white smoke) emitting from
exhaust
²Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test (Refer
to 9 - ENGINE - DIAGNOSIS AND TESTING). An
engine cylinder head gasket leaking between adja-
cent 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 WITH COOLANT PRES-
SURE CAP REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure
cap. Start the engine and allow it to warm up until
thermostat opens.
If a large combustion/compression pressure leak
exists, bubbles will be visible in the coolant.
COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE PRESSURE BUILT UP, BY CONTINUOUS
ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to
pressure cap neck. Start the engine and observe the
tester's pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also
be checked by using Bloc-Chek Kit C-3685-A or
equivalent. Perform test following the procedures
supplied with the tool kit.
REMOVAL - CYLINDER HEAD
(1) Perform fuel system pressure release procedure
before attempting any repairs.(Refer to 14 -FUEL SYSTEM/FUEL DELIVERY - SPECIFICA-
TIONS)
(2) Disconnect battery negative cable.
(3) Drain cooling system. (Refer to 7 - COOLING -
STANDARD PROCEDURE)
(4) Remove air filter housing and inlet tube.
(5) Remove intake manifold.
(6) Remove heater tube support bracket from cyl-
inder head.
(7) Disconnect radiator upper and heater supply
hoses from water outlet connections.
(8) Remove accessory drive belts. (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL)
(9) Raise vehicle and remove exhaust pipe from
manifold.
(10) Remove power steering pump and set aside.
Do not disconnect lines.
(11) Remove accessory drive bracket
(12) Remove ignition coil and wires from engine.
(13) Disconnect cam sensor and fuel injector wir-
ing connectors.
(14) Remove timing belt and camshaft sprockets.
(Refer to 9 - ENGINE/VALVE TIMING/TIMING
BELT/CHAIN AND SPROCKETS - REMOVAL)
(15) Remove timing belt idler pulley and rear tim-
ing belt cover. (Refer to 9 - ENGINE/VALVE TIM-
ING/TIMING BELT / CHAIN COVER(S) -
REMOVAL)
(16) Remove cylinder head cover. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL)
(17) Remove camshafts (Refer to 9 - ENGINE/
CYLINDER HEAD/CAMSHAFT(S) - REMOVAL).
NOTE: Identify rocker arm position to ensure cor-
rect re-installation in original position, if reused.
(18) Remove rocker arms. (Refer to 9 - ENGINE/
CYLINDER HEAD/ROCKER ARMS - REMOVAL).
(19) Remove cylinder head bolts in REVERSE
sequence of tightening.
(20) Remove cylinder head from engine block.
(21) Inspect and clean cylinder head. (Refer to 9 -
ENGINE/CYLINDER HEAD - INSPECTION) (Refer
to 9 - ENGINE/CYLINDER HEAD - CLEANING)
CLEANING
To ensure engine gasket sealing, proper surface
preparation must be performed, especially with the
use of aluminum engine components and multi-layer
steel cylinder head gaskets.
NOTE: Multi-Layer Steel (MLS) head gaskets require
a scratch free sealing surface.
9s - 20 ENGINEKJ
CYLINDER HEAD (Continued)

(2) Spray a small stream of water (Spray Bottle) at
the suspected leak area.
(3) If engine RPM'S change, the area of the sus-
pected leak has been found.
(4) Repair as required.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Disconnect connector from inlet air tempera-
ture sensor.
(3) Disconnect air intake tube at throttle body and
remove upper air cleaner housing.
(4) Disconnect connector from throttle position
sensor (TPS).
(5) Disconnect connector from idle air control (IAC)
motor.
(6) Disconnect connector from MAP sensor.
(7) Remove vacuum lines for purge solenoid and
PCV valve at intake manifold.
(8) Remove vacuum lines for power brake booster,
LDP, EGR transducer, and speed control vacuum res-
ervoir (if equipped) at intake manifold fittings.
(9) Disconnect throttle, speed control (if equipped),
and transaxle control (if equipped) and cables from
throttle lever and bracket. (Refer to 14 - FUEL SYS-
TEM/FUEL INJECTION/THROTTLE CONTROL
CABLE - REMOVAL)
(10) Perform fuel system pressure release proce-
durebefore attempting any repairs.(Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY - STANDARD
PROCEDURE)
(11) Disconnect fuel line. (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/QUICK CONNECT FIT-
TING - STANDARD PROCEDURE)
(12) Disconnect coolant temperature sensor/fuel
injector wire harness connector.
(13) Disconnect fuel injector harness.
(14) Remove intake manifold to cylinder head fas-
teners.
(15) Remove the manifold from engine.
CAUTION: Cover intake manifold openings to pre-
vent foreign material from entering engine.
(16) Inspect the manifold. (Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - INSPECTION)
INSPECTION
(1) Check manifold surfaces for flatness with
straight edge. Surface must be flat within 0.15 mm
per 300 mm (0.006 in. per foot) of manifold length.
(2) Inspect manifold for cracks or distortion.
Replace manifold if necessary.
INSTALLATION
(1) Clean manifold sealing surfaces.
(2) Install new manifold to cylinder head seals.
(3) Install manifold to head.
(4) Install and tighten intake manifold fasteners to
28 N´m (250 in. lbs.) in the sequence shown (Fig. 90).
Repeat procedure until all bolts are at specified
torque.
(5) Install throttle cables in bracket.
(6) Connect throttle, speed control, (if equipped),
cables to throttle lever.
(7) Connect vacuum lines for power brake booster,
LDP, EGR transducer, and speed control vacuum res-
ervoir (if equipped) at upper intake manifold fittings.
(8) Connect vacuum lines for purge solenoid and
PCV valve.
(9) Connect electrical connectors for MAP sensor,
throttle position sensor (TPS), and idle air control
(IAC) motor.
(10) Connect the fuel line. (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY/QUICK CONNECT FIT-
TING - STANDARD PROCEDURE)
(11) Connect coolant temperature sensor/fuel injec-
tor wiring harness electrical connector.
(12) Install the air cleaner housing and air intake
tube to throttle body.
(13) Connect inlet air temperature sensor connec-
tor.
(14) Connect negative cable to battery.
Fig. 90 LOWER INTAKE MANIFOLD TIGHTENING
SEQUENCE
9s - 52 ENGINEKJ
INTAKE MANIFOLD (Continued)

TIMING BELT AND
SPROCKET(S)
REMOVAL
REMOVAL - TIMING BELT
(1) Remove air cleaner upper cover, housing, and
clean air tube.
(2) Raise vehicle on hoist.
(3) Remove accessory drive belts. (Refer to 7 -
COOLING/ACCESSORY DRIVE/BELT TENSION-
ERS - REMOVAL)
(4) Remove crankshaft vibration damper. (Refer to
9 - ENGINE/ENGINE BLOCK/VIBRATION
DAMPER - REMOVAL)
(5) Remove air conditioner/generator belt tensioner
and pulley assembly. (Refer to 7 - COOLING/ACCES-
SORY DRIVE/BELT TENSIONERS - REMOVAL)
(6) Remove timing belt lower front cover bolts and
remove cover. (Refer to 9 - ENGINE/VALVE TIMING/
TIMING BELT / CHAIN COVER(S) - REMOVAL)
(7) Lower vehicle.
(8) Remove bolts attaching timing belt upper front
cover and remove cover. (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT / CHAIN COVER(S)
- REMOVAL)
CAUTION: When aligning crankshaft and camshaft
timing marks always rotate engine from crankshaft.
Camshaft should not be rotated after timing belt is
removed. Damage to valve components may occur.
Always align timing marks before removing timing
belt.
(9) Before the removal of the timing belt, rotate
crankshaft until the TDC mark on oil pump housing
aligns with the TDC mark on crankshaft sprocket
(trailing edge of sprocket tooth) (Fig. 95).
NOTE: The crankshaft sprocket TDC mark is
located on the trailing edge of the sprocket tooth.
Failure to align trailing edge of sprocket tooth to
TDC mark on oil pump housing will cause the cam-
shaft timing marks to be misaligned.
(10) Install 6 mm Allen wrench into belt tensioner.
Before rotating the tensioner, insert the long end of a
1/8º or 3 mm Allen wrench into the pin hole on the
front of the tensioner (Fig. 96). While rotating the
tensioner counterclockwise, push in lightly on the
1/8º or 3 mm Allen wrench, until it slides into the
locking hole.
(11) Remove timing belt.
REMOVAL - CRANKSHAFT SPROCKET
(1) Disconnect negative battery cable.
(2) Remove timing belt (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - REMOVAL).
(3) Remove crankshaft sprocket using Special
Tools 6793 and insert C-4685-C2 (Fig. 97).
CLEANING
Do Not attempt to clean a timing belt. If contami-
nation from oil, grease, or coolants have occurred, the
timing belt should be replaced.
Clean all sprockets using a suitable solvent. Clean
all sprocket grooves of any debris.
Fig. 95 Crankshaft and Camshaft Timing
1 - CAMSHAFT TIMING MARKS
2 - CRANKSHAFT TDC MARKS
3 - TRAILING EDGE OF SPROCKET TOOTH
KJENGINE9s-55

SPECIFICATIONS
FUEL SYSTEM PRESSURE
339 kPa +/- 34 kPa (49.2 psi +/- 2 psi).
TORQUE
DESCRIPTION N-m Ft. Lbs. In. Lbs.
Accelerator Pedal Bracket Mounting Nuts 12 - 105
Crankshaft Position Sensor - 2.4L 28 21 -
Crankshaft Position Sensor - 3.7L 28 21 -
Camshaft Position Sensor - 2.4L 12 - 106
Camshaft Position Sensor - 3.7L 12 - 106
Engine Coolant Temperature Sensor 11 - 96
EVAP Canister-to-Body Bolts 48 35 -
EVAP Canister-to-Canis. Bracket Bolt/Nut 11 - 100
Fuel Filler Hose Clamp at Tank 3 - 30
Fuel Filler Housing-to-Body Screws 2 - 17
Fuel Filter Mounting Nut at Tank 5.5 - 49
Fuel Pump Module Access Plate Nuts 3 - 26
Fuel Rail Mounting Bolts - 3.7L 11 - 100
Fuel Rail Mounting Bolts - 2.4L 28 - 250
Fuel Tank Heat Sheild Nuts 5.5 - 49
Fuel Tank Mounting Strap Bolts 61 45 -
Fuel Tank Skid Plate and Trailer Hitch 88 65 -
IAC Motor Mounting Screws 7 - 60
Leak Detection Pump Mounting Bracket-to-Fuel
Tank Nuts5.5 - 49
Leak Detection Pump-to-Bracket Nuts 1.2 - 11
Map Sensor Mounting Screws 3 - 25
PCM-to-Mounting Bracket Mounting Screws 4 - 35
Power Steering Pressure Switch 14-22 - 124-195
TPS Mounting Screws 7 - 60
Throttle Body Mounting Bolts 11 - 100
Oxygen Sensors 30 22 -
KJFUEL DELIVERY 14 - 5
FUEL DELIVERY (Continued)

of the firing of the fuel injectors. It isnot usedas a
fuel pressure regulator. The fuel pressure regulator is
not mountedto the fuel rail on any engine. It is
located on the fuel tank mounted fuel pump module.
Refer to Fuel Pressure Regulator for additional infor-
mation.
The fuel rail is not repairable.
A quick-connect fitting with a safety latch is used
to attach the fuel line to the fuel rail.
3.7L
High pressure fuel from the fuel pump is routed to
the fuel rail. The fuel rail then supplies the neces-
sary fuel to each individual fuel injector.
A quick-connect fitting with a safety latch is used
to attach the fuel line to the fuel rail.
The fuel rail is not repairable.
REMOVAL
2.4L
WARNING: THE FUEL SYSTEM IS UNDER CON-
STANT PRESSURE EVEN WITH ENGINE OFF.
BEFORE SERVICING FUEL RAIL, FUEL SYSTEM
PRESSURE MUST BE RELEASED.
The fuel rail can be removed without removing the
intake manifold if the following procedures are fol-
lowed.(1) Remove fuel tank filler tube cap.
(2) Perform Fuel System Pressure Release Proce-
dure.
(3) Remove negative battery cable at battery.
(4) Remove air duct at throttle body.
(5) Disconnect fuel line latch clip and fuel line at
fuel rail. A special tool will be necessary for fuel line
disconnection. Refer to Quick-Connect Fittings.
(6) Remove necessary vacuum lines at throttle
body.
(7) Drain engine coolant and remove thermostat
and thermostat housing.
(8) Remove PCV hose and valve at valve cover.
(9) Remove 3 upper intake manifold mounting
bolts (Fig. 35), but only loosen 2 lower bolts about 2
turns.
(10) Disconnect 2 main engine harness connectors
at rear of intake manifold (Fig. 34).
(11) Disconnect 2 injection wiring harness clips at
harness mounting bracket (Fig. 35).
(12) Disconnect electrical connectors at all 4 fuel
injectors. To remove connector refer to (Fig. 37). Push
red colored slider away from injector (1). While push-
ing slider, depress tab (2) and remove connector (3)
from injector. The factory fuel injection wiring har-
ness is numerically tagged (INJ 1, INJ 2, etc.) for
injector position identification. If harness is not
tagged, note wiring location before removal.
(13) Remove 2 injection rail mounting bolts (Fig.
31).
Fig. 34 MAP SENSOR LOCATION-2.4L
1 - REAR OF INTAKE MANIFOLD
2 - MAP SENSOR
3 - ALIGNMENT PIN
4 - MOUNTING BOLT (TORX)
5 - ELECTRICAL CONNECTOR
6 - MAIN ENGINE HARNESS CONNECTORS
Fig. 35 FUEL RAIL MOUNTING-2.4L
1 - FUEL RAIL
2 - INJECTION HARNESS CLIPS
3 - LOWER MOUNTING HOLES
4 - UPPER MOUNTING HOLES
5 - INTAKE MANIFOLD
14 - 22 FUEL DELIVERYKJ
FUEL RAIL (Continued)

(14) If fuel injectors are to be removed, refer to
Fuel Injector Removal/Installation.
INSTALLATION
2.4L Engine
(1) If fuel injectors are to be installed, refer to Fuel
Injector Removal/Installation.
(2) Clean out fuel injector machined bores in
intake manifold.
(3) Apply a small amount of engine oil to each fuel
injector o-ring. This will help in fuel rail installation.
(4) Position fuel rail/fuel injector assembly to
machined injector openings in intake manifold.
(5) Guide each injector into cylinder head. Be care-
ful not to tear injector o-rings.
(6) Push fuel rail down until fuel injectors have
bottomed on shoulders.
(7) Install 2 fuel rail mounting bolts and tighten.
Refer to torque specifications.
(8) Connect electrical connectors at all fuel injec-
tors. To install connector, refer to (Fig. 37). Push con-
nector onto injector (1) and then push and lock red
colored slider (2). Verify connector is locked to injec-
tor by lightly tugging on connector.
(9) Snap 2 injection wiring harness clips (Fig. 35)
into brackets.
(10) Connect 2 main engine harness connectors at
rear of intake manifold (Fig. 34).
(11) Tighten 5 intake manifold mounting bolts.
Refer to Engine Torque Specifications.
(12) Install PCV valve and hose.
(13) Install thermostat and radiator hose. Fill with
coolant. Refer to Cooling.
(14) Connect necessary vacuum lines to throttle
body.
(15) Connect fuel line latch clip and fuel line to
fuel rail. Refer to Quick-Connect Fittings.
(16) Install air duct to throttle body.
(17) Connect battery cable to battery.
(18) Start engine and check for leaks.
3.7L Engine
(1) If fuel injectors are to be installed, refer to Fuel
Injector Removal/Installation.
(2) Clean out fuel injector machined bores in
intake manifold.
(3) Apply a small amount of engine oil to each fuel
injector o-ring. This will help in fuel rail installation.
(4) Position fuel rail/fuel injector assembly to
machined injector openings in cylinder head.
(5) Guide each injector into cylinder head. Be care-
ful not to tear injector o-rings.
(6) Pushrightside of fuel rail down until fuel
injectors have bottomed on cylinder head shoulder.Pushleftfuel rail down until injectors have bot-
tomed on cylinder head shoulder.
(7) Install 4 fuel rail mounting bolts and tighten.
Refer to torque specifications.
(8) Install 6 ignition coils. Refer to Ignition Coil
Removal/Installation.
(9) Connect electrical connectors to throttle body.
(10) Connect electrical connectors at all fuel injec-
tors. To install connector, refer to (Fig. 37). Push con-
nector onto injector (1) and then push and lock red
colored slider (2). Verify connector is locked to injec-
tor by lightly tugging on connector.
(11) Connect necessary vacuum lines to throttle
body.
(12) Connect fuel line latch clip and fuel line to
fuel rail. Refer to Quick-Connect Fittings.
(13) Install air box to throttle body.
(14) Install air duct to air box.
(15) Connect battery cable to battery.
(16) Start engine and check for leaks.
FUEL TANK
DESCRIPTION
The fuel tank is constructed of a plastic material.
Its main functions are for fuel storage and for place-
ment of the fuel pump module, and certain ORVR
components.
OPERATION
All models pass a full 360 degree rollover test
without fuel leakage. To accomplish this, fuel and
vapor flow controls are required for all fuel tank con-
nections.
A check (control) valve is mounted into the top sec-
tion of the 2±piece fuel pump module. Refer to Fuel
Tank Check Valve for additional information.
An evaporation control system is connected to the
fuel tank to reduce emissions of fuel vapors into the
atmosphere. When fuel evaporates from the fuel
tank, vapors pass through vent hoses or tubes to a
charcoal canister where they are temporarily held.
When the engine is running, the vapors are drawn
into the intake manifold. Certain models are also
equipped with a self-diagnosing system using a Leak
Detection Pump (LDP) and/or an ORVR system.
Refer to Emission Control System for additional
information.
14 - 24 FUEL DELIVERYKJ
FUEL RAIL (Continued)

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)