2002 JEEP LIBERTY 3.7 v6

INSTALLATION
WARNING: REVIEW THE WARNINGS AND CAU-
TIONS IN THE FRONT OF THIS SECTION BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - WARNING) (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - CAUTION) (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
CAUTION - REFRIGERANT HOSES/LINES/TUBES
PRECAUTIONS)
The compressor may be removed and repositioned
without disconnecting the refrigerant lines or dis-
charging the refrigerant system. Discharging is not
necessary if servicing the compressor clutch or clutch
coil, the engine, the cylinder head, or the generator.
NOTE: If a replacement compressor is being
installed, be certain to check the refrigerant oil
level. (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING/REFRIGERANT OIL - STANDARD PRO-
CEDURE - REFRIGERANT OIL LEVEL) Use only
refrigerant oil of the type recommended for the
compressor in the vehicle. (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING/REFRIGERANT OIL -
DESCRIPTION)(1) Install the compressor to the mounting bracket.
Tighten the three mounting bolts to 27 N´m (20 ft.
lbs.), (2.4L gasoline and 2.5L diesel engines only).
(2) On the 3.7L gasoline engine install and tighten
the bolts in the following sequence (Fig. 5):
²The number one bolt (rear) is hand tightened
first then tightened to 55 N´m (41 ft. lbs.)
²The number three bolt is then hand tightened
and torqued to 40 N´m ( 30 ft. lbs.)
²The number two bolt is also hand tightened and
torqued to 55 N´m ( 41 ft. lbs.)
(3) Remove the tape or plugs from all of the
opened refrigerant line fittings. Install the suction
and discharge line manifold to the compressor.
Tighten the fastener to 28 N´m (250 in. lbs.).(Refer to
24 - HEATING & AIR CONDITIONING/PLUMBING/
SUCTION LINE - INSTALLATION) (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/A/C
DISCHARGE LINE - INSTALLATION)
(4) Install the serpentine drive belt(Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
Fig. 3 A/C COMPRESSOR - 3.7L ENGINE
1 - COMPRESSOR BOLT #1
2 - COMPRESSOR BOLT #2
3 - COMPRESSOR BOLT #3
4 - A/C COMPRESSOR
5 - A/C COMPRESSOR CLUTCH AND PULLEY
6 - COMPRESSOR MOUNT
Fig. 4 A/C COMPRESSOR - 2.5L DIESEL ENGINE
1 - SUCTION LINE MOUNTING NUT
2- SUCTION LINE MOUNTING CLIP
3- SUCTION LINE
4- MOUNTING SCREW FOR SUCTION LINE
5- SUCTION LINE MOUNTING FLANG
6- MOUNTING SCREW FOR DISCHARGE LINE
7- DISCHARGE LINE MOUNTING FLANG
8- A/C PRESSURE SENSOR
9- A/C DISCHARGE LINE
10- A/C COMPRESSOR ASSEMBLY
11- A/C DISCHARGE LINE SERVICE PORT
24 - 44 PLUMBINGKJ
A/C COMPRESSOR (Continued)

(5) Plug in the compressor clutch coil wire harness
connector.
(6) Connect the battery negative cable.
(7) Evacuate the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM EVACUATE)
(8) Charge the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM CHARGE)
A/C CONDENSER
DESCRIPTION
The condenser is located in the air flow in front of
the engine cooling radiator. The condenser is a heat
exchanger that allows the high-pressure refrigerant
gas being discharged by the compressor to give up its
heat to the air passing over the condenser fins.
OPERATION
When the refrigerant gas gives up its heat, it con-
denses. When the refrigerant leaves the condenser, it
has become a high-pressure liquid refrigerant. Thevolume of air flowing over the condenser fins is crit-
ical to the proper cooling performance of the air con-
ditioning system. Therefore, it is important that
there are no objects placed in front of the radiator
grille openings in the front of the vehicle or foreign
material on the condenser fins that might obstruct
proper air flow. Also, any factory-installed air seals or
shrouds must be properly reinstalled following radia-
tor or condenser service.
The condenser cannot be repaired and, if faulty or
damaged, it must be replaced.
REMOVAL
WARNING: REVIEW THE WARNINGS AND CAU-
TIONS IN THE FRONT OF THIS SECTION BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - WARNING) (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - CAUTION)
(1) Disconnect and isolate the battery negative
cable.
(2) Recover the refrigerant from the refrigerant
system. (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - STANDARD PROCEDURE -
REFRIGERANT RECOVERY)
(3) Disconnect the discharge line refrigerant line
fitting at the condenser inlet. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - STAN-
DARD PROCEDURE - A/C LINE COUPLERS)
Install plugs in, or tape over all of the opened refrig-
erant line fittings.
(4) Disconnect the liquid line (Left-Hand Drive) or
liquid line jumper (Right-Hand Drive) refrigerant
line fitting at the condenser outlet. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - A/C LINE COUPLERS)
Install plugs in, or tape over all of the opened refrig-
erant line fittings.
(5) Remove the radiator and the condenser from
the vehicle as a unit. Refer to Cooling for the proce-
dures.
(6) Remove the two nuts that secure the condenser
studs to the upper brackets of the radiator (Fig. 6).
(7) Slide the condenser down from the radiator far
enough for the condenser studs to clear the upper
radiator bracket holes, and for the lower condenser
bracket holes to clear the dowel pins on the bottom of
the radiator.
(8) Remove the condenser from the radiator.
Fig. 5 A/C COMPRESSOR - 3.7L ENGINE
1 - COMPRESSOR BOLT #1
2 - COMPRESSOR BOLT #2
3 - COMPRESSOR BOLT #3
4 - A/C COMPRESSOR
5 - A/C COMPRESSOR CLUTCH AND PULLEY
6 - COMPRESSOR MOUNT
KJPLUMBING 24 - 45
A/C COMPRESSOR (Continued)

(M)Malfunction Indicator Lamp (MIL) illuminated during engine operation if this DTC was recorded
(depending if required by CARB and/or EPA). MIL is displayed as an engine icon on instrument panel.
(G)Generator lamp illuminated
Generic Scan
Tool P-CodeDRB Scan Tool Display Brief Description of DTC
P0712 (M) Trans Temp Sensor Voltage Too Low Voltage less than 1.55 volts (4-speed auto. trans. only).
P0713 Trans Temp Sensor Voltage Too
HighTransmission fluid temperature sensor input above
acceptable voltage. Was MIL code 37.
P0713 (M) Trans Temp Sensor Voltage Too
HighVoltage greater than 3.76 volts (4-speed auto. trans.
only).
P0720 (M) Low Output SPD Sensor RPM,
Above 15 MPHThe relationship between the Output Shaft Speed Sensor
and vehicle speed is not within acceptable limits.
P0720 (M) Low Output Spd Sensor RPM Above
15 mphOutput shaft speed is less than 60 rpm with vehicle speed
above 15 mph (4-speed auto. trans. only).
P0740 (M) Torq Con Clu, No RPM Drop at
LockupRelationship between engine and vehicle speeds
indicated failure of torque convertor clutch lock-up system
(TCC/PTU solenoid)
P0743 (M) Torque Converter Clutch Solenoid/
Trans Relay CircuitsAn open or shorted condition detected in the torque
converter clutch (part throttle unlock) solenoid control
circuit. Shift solenoid C electrical fault - Aisin transmission
P0743 (M) Torque Converter Clutch Solenoid/
Trans Relay CircuitsAn open or shorted condition detected in the torque
converter part throttle unlock solenoid control circuit (3 or
4-speed auto. trans. only).
P0748 (M) Governor Pressur Sol Control/Trans
Relay CircuitsAn open or shorted condition detected in the Governor
Pressure Solenoid circuit or Trans Relay Circuit in JTEC
RE transmissions.
P0748 (M) Governor Pressure Sol Control/Trans
Relay CircuitsAn open or shorted condition detected in the governor
pressure solenoid or relay circuits (4-speed auto. trans.
only).
P0751 (M) O/D Switch Pressed (Lo) More Than
5 MinutesOverdrive override switch input is in a prolonged
depressed state.
P0751 (M) O/D Switch Pressed (LO) More Than
5 MinOverdrive Off switch input too low for more than 5
minutes (4-speed auto. trans. only).
P0753 (M) Trans 3-4 Shift Sol/Trans Relay
CircuitsAn open or shorted condition detected in the overdrive
solenoid control circuit or Trans Relay Circuit in JTEC RE
transmissions. Was MIL code 45.
P0753 (M) Trans 3-4 Shift Sol/Trans Relay
CircuitsAn open or shorted condition detected in the transmission
2-4 shift solenoid circuit (4-speed auto. trans. only).
P0756 AW4 Shift Sol B (2-3) Functional
FailureShift solenoid B (2-3) functional fault - Aisin transmission
P0783 (M) 3-4 Shift Sol, No RPM Drop at
LockupThe overdrive solenoid is unable to engage the gear
change from 3rd gear to the overdrive gear.
P0801 Reverse Gear Lockout Circuit Open
or ShortAn open or shorted condition detected in the transmission
reverse gear lock-out solenoid control circuit.
P0830 Clutch Depressed Switch Circuit Problem detected in clutch switch circuit.
P0833 Clutch Released Switch Circuit Problem detected in clutch switch circuit.
P0836 4WD Mux Switch Circuit
P0837 4WD Mux Switch Performance
25 - 10 EMISSIONS CONTROLKJ
EMISSIONS CONTROL (Continued)

SPECIFICATIONS
TORQUE
DESCRIPTION N-m Ft. Lbs. In. Lbs.
Accelerator Pedal Bracket
Mounting Nuts12 - 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
Sensor11 - 9 6
EVAP Canister-to-Body Bolts 48 35 -
EVAP Canister-to-Canis. Bracket
Bolt/Nut11 - 100
Fuel Filler Hose Clamp at Tank 3 - 30
Fuel Filler Housing-to-Body
Screws2-17
Fuel Filter Mounting Nut at Tank 5.5 - 49
Fuel Pump Module Access Plate
Nuts3-26
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
Hitch88 65 -
IAC Motor Mounting Screws 7 - 60
Leak Detection Pump Mounting
Bracket-to-Fuel Tank Nuts5.5 - 49
Leak Detection Pump-to-Bracket
Nuts1.2 - 11
Map Sensor Mounting Screws 3 - 25
PCM-to-Mounting Bracket
Mounting Screws4-35
Power Steering Pressure Switch 14-22 - 124-195
TPS Mounting Screws 7 - 60
Throttle Body Mounting Bolts 11 - 100
Oxygen Sensors 30 22 -
25 - 26 EVAPORATIVE EMISSIONSKJ
EVAPORATIVE EMISSIONS (Continued)

(4) Carefully install vapor/vacuum lines to LDP,
and install hose to LDP filter.The vapor/vacuum
lines and hoses must be firmly connected.
Check the vapor/vacuum lines at the LDP, LDP
filter and EVAP canister duty cycle purge sole-
noid for damage or leaks. If a leak is present, a
Diagnostic Trouble Code (DTC) may be set.
ORVR
DESCRIPTION
The ORVR (On-Board Refueling Vapor Recovery)
system consists of a unique fuel tank, flow manage-
ment valve, fluid control valve, one-way check valve
and vapor canister (Fig. 1).
OPERATION
The ORVR (On-Board Refueling Vapor Recovery)
system is used to remove excess fuel tank vapors.
This is done while the vehicle is being refueled. Cer-
tain ORVR components can be found in (Fig. 1).
Fuel flowing into the fuel filler tube (approx. 1º
I.D.) creates an aspiration effect drawing air into the
fuel fill tube. During refueling, the fuel tank is
vented to the EVAP canister to capture escaping
vapors. With air flowing into the filler tube, there are
no fuel vapors escaping to the atmosphere. Once the
refueling vapors are captured by the EVAP canister,the vehicle's computer controlled purge system draws
vapor out of the canister for the engine to burn. The
vapor flow is metered by the purge solenoid so that
there is no, or minimal impact on driveability or
tailpipe emissions.
As fuel starts to flow through the fuel fill tube, it
opens the normally closed check valve and enters the
fuel tank. Vapor or air is expelled from the tank
through the control valve and on to the vapor canis-
ter. Vapor is absorbed in the EVAP canister until
vapor flow in the lines stops. This stoppage occurs
following fuel shut-off, or by having the fuel level in
the tank rise high enough to close the control valve.
This control valve contains a float that rises to seal
the large diameter vent path to the EVAP canister.
At this point in the refueling process, fuel tank pres-
sure increases, the check valve closes (preventing liq-
uid fuel from spiting back at the operator), and fuel
then rises up the fuel filler tube to shut off the dis-
pensing nozzle.
PCV VALVE
DESCRIPTION
2.4L
The 2.4L 4-cylinder engine is equipped with a
closed crankcase ventilation system and a Positive
Crankcase Ventilation (PCV) valve.
This system consists of:
²a PCV valve attached to the left/front side of the
valve cover (Fig. 5). It is secured with 1 bolt. An
o-ring is used to seal valve to valve cover (Fig. 6).
²the air cleaner housing
²tubes and hoses to connect the system compo-
nents.
3.7L
The 3.7L V-6 engine is equipped with a closed
crankcase ventilation system and a Positive Crank-
case Ventilation (PCV) valve.
This system consists of:
²a PCV valve mounted to the oil filler housing
(Fig. 7). The PCV valve is sealed to the oil filler
housing with an o-ring.
²the air cleaner housing
²two interconnected breathers threaded into the
rear of each cylinder head (Fig. 8).
²tubes and hoses to connect the system compo-
nents.
Fig. 4 LDP ELECTRICAL CONNECTOR
1 - LEAK DETECTION PUMP (LDP)
2 - ELECTRICAL CONNECTOR
3 - FUEL FILTER
KJEVAPORATIVE EMISSIONS 25 - 29
LEAK DETECTION PUMP (Continued)

Fig. 5 PCV VALVE LOCATION - 2.4L
1 - P C V VA LV E
2 - HOSE
3 - MOUNTING BOLT
4 - VALVE COVER (LEFT SIDE)
Fig. 6 PCV VALVE AND O-RING - 2.4L
1 - P C V VA LV E
2 - O-RING
3 - MOUNTING BOLT
Fig. 7 PCV VALVE - 3.7L
1 - O-RING
2 - LOCATING TABS
3 - CAM LOCK
4 - OIL FILLER TUBE
5 - PCV LINE/HOSE
6 - P C V VA LV E
Fig. 8 CRANKCASE BREATHERS (2) - 3.7L
1 - CRANKCASE BREATHERS (2)
2 - REAR OF ENGINE
25 - 30 EVAPORATIVE EMISSIONSKJ
PCV VALVE (Continued)

OPERATION
The PCV system operates by engine intake mani-
fold vacuum. Filtered air is routed into the crankcase
through the air cleaner hose and crankcase breath-
er(s) (if used). The metered air, along with crankcase
vapors, are drawn through the PCV valve and into a
passage in the intake manifold. The PCV system
manages crankcase pressure and meters blow-by
gases to the intake system, reducing engine sludge
formation.
The PCV valve contains a spring loaded plunger.
This plunger meters the amount of crankcase vapors
routed into the combustion chamber based on intake
manifold vacuum.
TYPICALPCV valves are shown in (Fig. 9), (Fig.
10) and (Fig. 11).
When the engine is not operating, or during an
engine pop-back, the spring forces the plunger back
against the seat (Fig. 9). This will prevent vapors
from flowing through the valve.
During periods of high manifold vacuum, such as
idle or cruising speeds, vacuum is sufficient to com-
pletely compress spring. It will then pull the plunger
to the top of the valve (Fig. 10). In this position there
is minimal vapor flow through the valve.
During periods of moderate manifold vacuum, the
plunger is only pulled part way back from inlet. This
results in maximum vapor flow through the valve
(Fig. 11).
DIAGNOSIS AND TESTING - PCV VALVE
3.7L
(1) Disconnect PCV line/hose (Fig. 7) by discon-
necting rubber connecting hose at PCV valve fitting.
(2) Remove PCV valve at oil filler tube by rotating
PCV valve downward until locating tabs have been
freed at cam lock (Fig. 7). After tabs have cleared,
pull valve straight out from filler tube.To prevent
damage to PCV valve locating tabs, valve must
be pointed downward for removal. Do not force
valve from oil filler tube.
(3) After valve is removed, check condition of valve
o-ring (Fig. 7). Also, PCV valve should rattle when
shaken.
(4) Reconnect PCV valve to its connecting line/
hose.
(5) Start engine and bring to idle speed.
(6) If valve is not plugged, a hissing noise will be
heard as air passes through valve. Also, a strong vac-
uum should be felt with a finger placed at valve
inlet.
(7) If vacuum is not felt at valve inlet, check line/
hose for kinks or for obstruction. If necessary, clean
out intake manifold fitting at rear of manifold. Do
this by turning a 1/4 inch drill (by hand) through the
fitting to dislodge any solid particles. Blow out the
fitting with shop air. If necessary, use a smaller drill
to avoid removing any metal from the fitting.
(8)Do not attempt to clean the old PCV valve.
(9) Return PCV valve back to oil filler tube by
placing valve locating tabs (Fig. 7) into cam lock.
Press PCV valve in and rotate valve upward. A slight
click will be felt when tabs have engaged cam lock.
Valve should be pointed towards rear of vehicle.
(10) Connect PCV line/hose and connecting rubber
hose to PCV valve.
(11) Disconnect rubber hose from fresh air fitting
at air cleaner resonator box. Start engine and bring
to idle speed. Hold a piece of stiff paper (such as a
parts tag) loosely over the opening of the discon-
nected rubber hose.
(12) The paper should be drawn against the hose
opening with noticeable force. This will be after
allowing approximately one minute for crankcase
pressure to reduce.
Fig. 9 Engine Off or Engine Pop-BackÐNo Vapor
Flow
Fig. 10 High Intake Manifold VacuumÐMinimal
Vapor Flow
Fig. 11 Moderate Intake Manifold VacuumÐ
Maximum Vapor Flow
KJEVAPORATIVE EMISSIONS 25 - 31
PCV VALVE (Continued)

(13) If vacuum is not present, disconnect each PCV
system hose at top of each crankcase breather (Fig.
8). Check for obstructions or restrictions.
(14) If vacuum is still not present, remove each
PCV system crankcase breather (Fig. 8) from each
cylinder head. Check for obstructions or restrictions.
If plugged, replace breather. Tighten breather to 12
N´m (106 in. lbs.) torque. Do not attempt to clean
breather
(15) If vacuum is still not present, disconnect each
PCV system hose at each fitting and check for
obstructions or restrictions.
REMOVAL
2.4L
The PCV valve is attached to the left/front side of
the valve cover (Fig. 5). It is secured with 1 bolt. An
o-ring is used to seal valve to valve cover (Fig. 6).
(1) Remove hose from valve (Fig. 5). Check condi-
tion of hose.
(2) Remove 1 bolt.
(3) Remove PCV valve from valve cover.
(4) Check condition of valve o-ring.
3.7L
The PCV valve is located on the oil filler tube (Fig.
12). Two locating tabs are located on the side of the
valve (Fig. 12). These 2 tabs fit into a cam lock in the
oil filler tube. An o-ring seals the valve to the filler
tube.
(1) Disconnect PCV line/hose (Fig. 12) by discon-
necting rubber hose at PCV valve fitting.
(2) Remove PCV valve at oil filler tube by rotating
PCV valve downward (counter-clockwise) until locat-
ing tabs have been freed at cam lock (Fig. 12). After
tabs have cleared, pull valve straight out from filler
tube.To prevent damage to PCV valve locating
tabs, valve must be pointed downward for
removal. Do not force valve from oil filler tube.
(3) After valve is removed, check condition of valve
o-ring (Fig. 12).
INSTALLATION
2.4L
(1) Check condition of PCV valve o-ring.
(2) Install PCV valve into valve cover.
(3) Install PCV valve mounting bolt.
(4) Install hose to valve.3.7L
The PCV valve is located on the oil filler tube. Two
locating tabs are located on the side of the valve.
These 2 tabs fit into a cam lock in the oil filler tube.
An o-ring seals the valve to the filler tube.
(1) Return PCV valve back to oil filler tube by
placing valve locating tabs into cam lock. Press PCV
valve in and rotate valve upward. A slight click will
be felt when tabs have engaged cam lock. Valve
should be pointed towards rear of vehicle.
(2) Connect PCV line/hose and rubber hose to PCV
valve.
Fig. 12 PCV Valve/Oil Filler Tube Location
1 - O-RING
2 - LOCATING TABS
3 - CAM LOCK
4 - OIL FILLER TUBE
5 - PCV LINE/HOSE
6 - P C V VA LV E
25 - 32 EVAPORATIVE EMISSIONSKJ
PCV VALVE (Continued)