2003 CHRYSLER CARAVAN low oil pressure

CAUTION: The special screws used for attaching
the EGR tube and power steering reservoir to the
manifold must be installed slowly using hand tools
only. This requirement is to prevent the melting of
material that causes stripped threads. If threads
become stripped, an oversize repair screw is avail-
able. For more information and procedure (Refer to
9 - ENGINE/MANIFOLDS/INTAKE MANIFOLD - STAN-
DARD PROCEDURE - MANIFOLD STRIPPED
THREAD REPAIR).
(7) Install the power steering reservoir (Fig. 115).
Tighten screws to manifold to 5.6 N´m (50 in. lbs.).
(8) Connect throttle and speed control cables to
throttle body (Refer to 14 - FUEL SYSTEM/FUEL
INJECTION/THROTTLE CONTROL CABLE -
INSTALLATION)
(9) Attach make up air hose clip into the hole in
the throttle cable bracket.
(10) Connect the wiring connectors to the throttle
position sensor (TPS) and Automatic Idle Speed (AIS)
motor.
(11) Install air cleaner and air inlet hose assembly.
(12) Connect the inlet air temperature (IAT) sen-
sor electrical connector.
(13) Connect battery negative cable.
INTAKE MANIFOLD - LOWER
REMOVAL - LOWER INTAKE MANIFOLD
(1) Perform fuel system pressure release procedure
(before attempting any repairs).(Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY - STANDARD
PROCEDURE)
(2) Drain the cooling system. (Refer to 7 - COOL-
ING - STANDARD PROCEDURE)
(3) Remove the upper intake manifold. (Refer to 9
- ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL)
(4) Remove the fuel line. (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/FUEL LINES - STANDARD
PROCEDURE) (Refer to 14 - FUEL SYSTEM/FUEL
DELIVERY/QUICK CONNECT FITTING - STAN-
DARD PROCEDURE)
(5) Remove ignition coil and bracket (Fig. 119).
(6) Disconnect heater supply hose and engine cool-
ant temperature sensor (Fig. 120).
(7) Disconnect the fuel injector wire harness.
(8) Remove the fuel injectors and rail assembly
(Fig. 119).
(9) Remove radiator upper hose.
(10) Remove the intake manifold bolts.
(11) Remove lower intake manifold (Fig. 121).WARNING: INTAKE MANIFOLD GASKET IS MADE
OF VERY THIN METAL AND MAY CAUSE PER-
SONAL INJURY, HANDLE WITH CARE.
(12) Remove intake manifold seal retainers screws
(Fig. 121). Remove intake manifold gasket.
(13) Inspect and clean manifold. (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSPECTION) (Refer to 9 - ENGINE/MANIFOLDS/
INTAKE MANIFOLD - CLEANING)
CLEANING
(1) Discard gasket(s).
(2) Clean all sealing surfaces.
INSPECTION
Check for:
²Damage and cracks of each section.
²Clogged water passages in end cross-overs (if
equipped).
Fig. 119 FUEL RAIL AND IGNITION COIL &
BRACKET
1 - FUEL RAIL
2 - BOLT - FUEL RAIL
3 - NUT - IGNITION COIL
4 - BOLT - IGNITION COIL
5 - IGNITION COIL
6 - BRACKET - IGNITION COIL
7 - STUD - IGNITION COIL
8 - SEPARATOR - SPARK PLUG CABLE
9 - BRACKET - SPARK PLUG CABLE SEPARATOR
10 - BOLT - SEPARATOR BRACKET
11 - BRACKET - SPARK PLUG CABLE SEPARATOR
9 - 148 ENGINE 3.3/3.8LRS
INTAKE MANIFOLD - UPPER (Continued)
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OPERATION
Heat shields are needed to protect both the vehicle
and the environment from the high temperatures
developed near the catalytic converter.
Avoid application of rust prevention com-
pounds or undercoating materials to exhaust
system floor pan heat shields on cars so
equipped. Light over spray near the edges is
permitted. Application of coating will greatly
reduce the efficiency of the heat shields result-
ing in excessive floor pan temperatures and
objectionable fumes.
REMOVAL
(1) Raise vehicle on hoist.
(2) Remove fasteners attaching applicable heat
shield (Fig. 7), (Fig. 8), or (Fig. 9).
(3) Remove heat shield(s).
INSTALLATION
(1) Position heat shield(s) to underbody.
(2) Install heat shield fasteners and tighten to 2.6
N´m (23 in. lbs.) (Fig. 7), (Fig. 8), or (Fig. 9).
(3) Lower vehicle.
MUFFLER
REMOVAL
(1) Raise vehicle on a body contact type hoist.
NOTE: To provide removal clearance between muf-
fler/resonator pipe and rear axle parts, the rear sus-
pension must be relieved of all body weight.
(2) Apply a penetrating oil to clamp nuts of com-
ponent requiring removal.
CAUTION: When servicing the exhaust system, care
must be exercised not to dent or bend the bellows
of the flex-joint. Should this occur, the flex-joint will
eventually fail, requiring replacement of the cata-
lytic converter.
(3) Disconnect the right side axle half shaft from
the rear differential module (AWD equipped only).
(4) Loosen the band clamp (Fig. 10) at the muffler
to converter pipe connection.
(5) Remove the exhaust hangers to body screws
(Fig. 10).
(6) Separate muffler pipe from converter pipe.
(7) Remove muffler/resonator assembly by moving
assembly forward and guiding the resonator through
the rear axle to body opening.
(8) Clean ends of pipes or muffler to assure mat-
ing of all parts. Discard broken or worn insulators,
rusted clamps, supports and attaching parts.When
replacement is required on any component of
the exhaust system, it is important that original
equipment parts (or equivalent) be used for the
following conditions:
²Ensure proper alignment with other components
in the system.
²Provide acceptable exhaust noise levels.
²Provide proper exhaust system back pressure for
maintaining emission and performance levels.
INSTALLATION
(1) Install the muffler/resonator assembly by guid-
ing resonator between the rear axle and body.
(2) Connect the muffler pipe to the converter pipe
but do not tighten band clamp (Fig. 10).
(3) Position hangers to body and install screws
starting at the resonator working forward (Fig. 10).
Tighten hanger screws to 28 N´m (250 in. lbs.).
Fig. 8 MUFFLER HEAT SHIELD
1 - HEAT SHIELD - MUFFLER
2 - SCREW (QTY. 6)
Fig. 9 RESONATOR PIPE HEAT SHIELD
1 - SCREW (QTY. 3)
2 - HEAT SHIELD - RESONATOR PIPE
3 - MUFFLER
RSEXHAUST SYSTEM11-7
HEAT SHIELDS (Continued)
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(4) Position steering so front wheels are straight
ahead.
CAUTION: Do not rotate steering wheel after disen-
gaging lower coupling from steering gear, damage
to air bag clock spring can result.
(5) Remove clinch bolt attaching steering column
coupling to steering gear shaft (Fig. 10).
(6) Remove steering column coupling from tele-
scoping steering gear shaft.
(7) Hoist vehicle and support on safety stands.
(8) Position a drain pan under power steering
pump and oil return hose coupling.
(9) Using a hose pinch-off pliers (C-4390), pinch
power steering oil return hose off between the cross-
member coupling and the pump.
(10) Loosen hose clamp at the cradle crossmember
coupling.
(11) Disconnect return hose from metal tube.
(12) While holding pressure relief valve nut on
back of power steering pump, Remove flare nut
attaching high pressure hose to back of pump.
(13) Remove high pressure hose from pump.
(14) Allow power steering fluid to drain into pan.
(15) Remove bolts attaching anti-lock brake sensor
leads to cradle crossmember.
(16) Position anti-lock brake leads out of the way.
(17) Disconnect stabilizer bar links from ends of
stabilizer bar.
(18) Disconnect lower ball joints from lower steer-
ing knuckles (Refer to 2 - SUSPENSION/FRONT/
LOWER BALL JOINT - REMOVAL).
(19) Remove the rear engine mount heat shield
(Fig. 11).
(20) Remove through bolt attaching rear engine
mount to cradle crossmember (Fig. 12).
(21) Using paint or grease pencil, mark outline of
cradle crossmember on frame rails to aid installation.
(22) Support cradle crossmember on suitable lift-
ing device (Fig. 14).
(23) Remove bolts attaching crossmember to front
frame rails (Fig. 13).
(24) Remove cradle crossmember from vehicle (Fig.
14).
Fig. 10 STEERING COUPLING
1 - STEERING SHAFT BOOT
2 - STEERING SHAFT
3 - CROSSMEMBER
4 - STEERING GEAR
5 - MOUNT
6 - TRANSAXLE
Fig. 11 REAR MOUNT HEAT SHIELD
1 - BOLT
2 - HEAT SHIELD
3 - CLIP
4 - REAR ENGINE MOUNT
13 - 10 FRAME & BUMPERSRS
FRONT CRADLE CROSSMEMBER (Continued)
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When installing hoses, ensure that they are routed
away from contact with other vehicle components
that could rub against them and cause failure. Avoid
contact with clamps or other components that cause
abrasions or scuffing. Ensure that rubber hoses are
properly routed and avoid heat sources.
The hose clamps have rolled edges to prevent the
clamp from cutting into the hose. Only use clamps
that are original equipment or equivalent. Other
types of clamps may cut into the hoses and cause
high pressure fuel leaks. Tighten hose clamps to 1
N´m (9 in. lbs.) torque.
Inspect all hose connections such as clamps, cou-
plings and fittings to make sure they are secure and
leaks are not present. The component should be
replaced immediately if there is any evidence of deg-
radation that could result in failure.
Never attempt to repair a plastic fuel line/tube.
Replace as necessary.
Avoid contact of any fuel tubes/hoses with other
vehicle components that could cause abrasions or
scuffing. Be sure that the plastic fuel lines/tubes are
properly routed to prevent pinching and to avoid heat
sources.
FUEL PRESSURE REGULATOR
OPERATION
The fuel system uses a nonadjustable pressure reg-
ulator that maintains fuel system pressure at
approximately 400  34 kPa (58  5 psi). The fuel
pressure regulator contains a diaphragm, calibrated
spring and a fuel return valve. The spring pushes
down on the diaphragm and closes off the fuel return
port. System fuel pressure reflects the amount of fuel
pressure required to open the return port.
The pressure regulator is a mechanical device that
is NOT controlled by the PCM or engine vacuum.
REMOVAL
The fuel pressure regulator is part of the fuel
pump module (Fig. 9). Remove the fuel pump module
from the fuel tank to access the fuel pressure regula-
tor. Refer to the Fuel Pump Module removal in this
section.
(1) Spread tangs on pressure regulator retainer.
(2) Pry fuel pressure regulator out of housing.
(3) Ensure both upper and lower O-rings were
removed with regulator.
INSTALLATION
The fuel pressure regulator is part of the fuel
pump module. Remove the fuel pump module from
the fuel tank to access the fuel pressure regulator.Refer to the Fuel Pump Module removal in this sec-
tion.
(1) Lightly lubricate the O-rings with clean engine
oil and place them into opening in pump module (Fig.
9).
(2) Push regulator into opening in pump module.
(3) Fold tangs on regulator retainer over tabs on
housing.
FUEL PUMP
DESCRIPTION
The electric fuel pump is located in and is part of
the fuel pump module. It is a positive displacement,
gerotor type, immersible pump with a permanent
magnet electric motor. The fuel pump module is sus-
pended in fuel in the fuel tank.
OPERATION
The pump draws fuel through a strainer and
pushes it through the motor to the outlet. The pump
contains a check valve. The valve, in the pump out-
let, maintains pump pressure during engine off con-
ditions, for a short while. It is normal for fuel
pressure to drop to zero after cooldown. The fuel
pump relay provides voltage to the fuel pump. The
fuel pump has a maximum deadheaded pressure out-
put of approximately 880 kPa (130 psi). The regula-
tor adjusts fuel system pressure to approximately
400 kpa  34 kpa (58 psi   5 psi).
NOTE: Checkvalve maintains volume of fuel in the
rail and lines, not pressure.
Fig. 9 Fuel Pressure Regulator O-rings
1 - UPPER O-RING
2 - LOWER 0-RING
RSFUEL DELIVERY14-7
FUEL LINES (Continued)
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REMOVAL
(1) Remove fuel filler cap and perform Fuel Sys-
tem Pressure Release procedure (Fig. 15).
(2) Disconnect negative cable from battery.
(3) Insert fuel siphon hose into fuel filler neck and
push it into the tank.
(4) Drain fuel tank dry into holding tank or a
properly labeledGASOLINEsafety container.
(5) Raise vehicle on hoist and support.
(6) Use a transmission jack to support fuel tank.
Remove bolts from fuel tank straps.
(7) Lower tank slightly.
(8) Disconnect the fuel filler vent tube. Squeeze
tabs and pull apart (Fig. 16).
(9) Disconnect the fuel fill hose at the fuel tank
filler metal tubeNOT AT THE FUEL TANK(Fig.
16).
(10) Disconnect fuel line and vapor line at the
front of the fuel tank.
The fuel pump module electrical connector
has a retainer that locks it in place.
(11) Slide fuel pump module electrical connector
lock to unlock (Fig. 17).
(12) Push down on connector retainer (Fig. 18) and
pull connector off module.
(13) Lower tank from vehicle. Remove fuel filler
vent tube from frame (Fig. 19).
INSTALLATION
(1) Position fuel tank on transmission jack. Con-
nect rollover valve hose. Connect fuel filler tube vent
hose and tighten clamp.
(2) Raise tank into position and carefully work
filler metal tube into the rubber hose on fuel tank. A
light coating of clean engine oil on the tube end may
be used to aid assembly.
(3) Feed filler vent line thru frame rail. Careful
not to cross lines.
Fig. 15 Fuel Tank
1 - ROLLOVER VALVE
2 - FUEL FILLER INLET
3 - ROLLOVER VALVE
4 - GROUND STRAP
5 - FUEL FILTER
6 - FUEL PUMP MODULEFig. 16 FUEL FILLER AND VENT TUBE
1 - Filler Tube
2 - Vent Tube
Fig. 17 Fuel Line Retainers and Pump Connector
Lock
1 - PUSH
2 - CONNECTOR LOCK
3 - QUICK CONNECT RETAINERS
RSFUEL DELIVERY14-11
FUEL TANK (Continued)
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1 second. Therefore, battery voltage is not supplied to
the fuel pump, ignition coil, fuel injectors and heated
oxygen sensors.
ENGINE START-UP MODE
This is an OPEN LOOP mode. If the vehicle is in
park or neutral (automatic transaxles) or the clutch
pedal is depressed (manual transaxles) the ignition
switch energizes the starter relay when the engine is
not running. The following actions occur when the
starter motor is engaged.
²If the PCM receives the camshaft position sensor
and crankshaft position sensor signals, it energizes
the Auto Shutdown (ASD) relay and fuel pump relay.
If the PCM does not receive both signals within
approximately one second, it will not energize the
ASD relay and fuel pump relay. The ASD and fuel
pump relays supply battery voltage to the fuel pump,
fuel injectors, ignition coil, (EGR solenoid and PCV
heater if equipped) and heated oxygen sensors.
²The PCM energizes the injectors (on the 69É
degree falling edge) for a calculated pulse width until
it determines crankshaft position from the camshaft
position sensor and crankshaft position sensor sig-
nals. The PCM determines crankshaft position within
1 engine revolution.
²After determining crankshaft position, the PCM
begins energizing the injectors in sequence. It adjusts
injector pulse width and controls injector synchroni-
zation by turning the individual ground paths to the
injectors On and Off.
²When the engine idles within  64 RPM of its
target RPM, the PCM compares current MAP sensor
value with the atmospheric pressure value received
during the Ignition Switch On (zero RPM) mode.
Once the ASD and fuel pump relays have been
energized, the PCM determines injector pulse width
based on the following:
²MAP
²Engine RPM
²Battery voltage
²Engine coolant temperature
²Inlet/Intake air temperature (IAT)
²Throttle position
²The number of engine revolutions since cranking
was initiated
During Start-up the PCM maintains ignition tim-
ing at 9É BTDC.
ENGINE WARM-UP MODE
This is an OPEN LOOP mode. The following inputs
are received by the PCM:
²Manifold Absolute Pressure (MAP)
²Crankshaft position (engine speed)
²Engine coolant temperature
²Inlet/Intake air temperature (IAT)²Camshaft position
²Knock sensor
²Throttle position
²A/C switch status
²Battery voltage
²Vehicle speed
²Speed control
²O2 sensors
The PCM adjusts injector pulse width and controls
injector synchronization by turning the individual
ground paths to the injectors On and Off.
The PCM adjusts ignition timing and engine idle
speed. Engine idle speed is adjusted through the idle
air control motor.
CRUISE OR IDLE MODE
When the engine is at operating temperature this
is a CLOSED LOOP mode. During cruising or idle
the following inputs are received by the PCM:
²Manifold absolute pressure
²Crankshaft position (engine speed)
²Inlet/Intake air temperature
²Engine coolant temperature
²Camshaft position
²Knock sensor
²Throttle position
²Exhaust gas oxygen content (O2 sensors)
²A/C switch status
²Battery voltage
²Vehicle speed
The PCM adjusts injector pulse width and controls
injector synchronization by turning the individual
ground paths to the injectors On and Off.
The PCM adjusts engine idle speed and ignition
timing. The PCM adjusts the air/fuel ratio according
to the oxygen content in the exhaust gas (measured
by the upstream and downstream heated oxygen sen-
sor).
The PCM monitors for engine misfire. During
active misfire and depending on the severity, the
PCM either continuously illuminates or flashes the
malfunction indicator lamp (Check Engine light on
instrument panel). Also, the PCM stores an engine
misfire DTC in memory, if 2nd trip with fault.
The PCM performs several diagnostic routines.
They include:
²Oxygen sensor monitor
²Downstream heated oxygen sensor diagnostics
during open loop operation (except for shorted)
²Fuel system monitor
²EGR monitor (if equipped)
²Purge system monitor
²Catalyst efficiency monitor
²All inputs monitored for proper voltage range,
rationality.
RSFUEL INJECTION14-19
FUEL INJECTION (Continued)
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OPERATION
Turning of the steering wheel is converted into lin-
ear (side-to-side) travel through the meshing of the
helical pinion teeth with the rack teeth in the steer-
ing gear. This travel pushes and pulls the tie rods to
change the direction of the vehicle's front wheels.
Power assist steering provided by the power steer-
ing pump is controlled by an open center, rotary type
control valve which directs oil from the pump to
either side of the integral rack piston upon demand.
Road feel is controlled by the diameter of a torsion
bar which initially steers the vehicle. As required
steering effort increases, as in a turn, the torsion bar
twists, causing relative rotary motion between the
rotary valve body and the valve spool. This move-
ment directs oil behind the integral rack piston
which, in turn, builds hydraulic pressure and assists
in the turning effort.
Manual steering control of the vehicle can be main-
tained if power steering assist is lost. However,
under this condition, steering effort is significantly
increased.
WARNING
WARNINGS AND CAUTIONS
WARNING: POWER STEERING FLUID, ENGINE
PARTS AND EXHAUST SYSTEM MAY BE
EXTREMELY HOT IF ENGINE HAS BEEN RUNNING.
DO NOT START ENGINE WITH ANY LOOSE OR DIS-
CONNECTED HOSES. DO NOT ALLOW HOSES TO
TOUCH HOT EXHAUST MANIFOLD OR CATALYST.
WARNING: FLUID LEVEL SHOULD BE CHECKED
WITH THE ENGINE OFF TO PREVENT PERSONAL
INJURY FROM MOVING PARTS.
CAUTION: When the system is open, cap all open
ends of the hoses, power steering pump fittings or
power steering gear ports to prevent entry of for-
eign material into the components.
REMOVAL
REMOVAL - LHD GEAR
(1) Remove cap from power steering fluid reser-
voir.
(2) Using a siphon pump, remove as much fluid as
possible from the power steering fluid reservoir.Use
care not to damage the filter mesh below the
fluid surface.
CAUTION: Locking the steering column in the
straight-ahead position will prevent the clockspring
from being accidentally over-extended when the
steering column is disconnected from the interme-
diate steering coupler.
(3) Position the steering wheel in the STRAIGHT-
AHEAD position. Lock the steering wheel in place
using a steering wheel holding tool.
(4) With the vehicle on the ground, disconnect the
steering column shaft coupler from the steering gear
intermediate coupler (Fig. 2).
Fig. 2 Steering Column Shaft To Intermediate Shaft
Attachment
1 - STEERING COLUMN SHAFT COUPLER
2 - NUT
3 - SAFETY PIN
4 - INTERMEDIATE SHAFT
5 - PINCH BOLT
RSGEAR19-27
GEAR (Continued)
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INSTALLATION
(1) Install the power steering fluid cooler on the
cradle crossmember reinforcement (Fig. 18). Install
the mounting bolts and tighten to 11 N´m (100 in.
lbs.).
(2) Install power steering fluid hoses on the cooler.
Be sure hose clamps are installed on hose past
the upset bead on the power steering cooler
tubes.
(3) Lower the vehicle to a point where front tires
are just off the ground.
(4) Perform Power Steering Pump Initial Opera-
tion procedure. (Refer to 19 - STEERING/PUMP -
STANDARD PROCEDURE)
HOSE - POWER STEERING
PRESSURE
REMOVAL
REMOVAL - 2.4L ENGINE
NOTE: Before proceeding, review all WARNINGS
and CAUTIONS. (Refer to 19 - STEERING/PUMP -
WARNING)(Refer to 19 - STEERING/PUMP - CAU-
TION)
(1) Remove cap from power steering fluid reser-
voir.
(2) Using a siphon pump, remove as much power
steering fluid as possible from power steering fluid
reservoir.
(3) Raise vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE)
(4) Remove front emissions vapor canister. (Refer
to 25 - EMISSIONS CONTROL/EVAPORATIVE
EMISSIONS/VAPOR CANISTER - REMOVAL)
(5) Place an oil drain pan under vehicle to catch
power steering fluid.
(6) Back out pressure hose tube nut at power
steering pump pressure fitting and remove hose from
pump (Fig. 19).
(7) Remove bolt attaching right routing clamp to
front suspension cradle crossmember (Fig. 19).
Remove pressure hose from clamp.
(8) Back out pressure hose tube nut at power
steering gear and remove hose from gear (Fig. 19).
(9) Remove power steering fluid pressure hose
from vehicle.
REMOVAL - 3.3L/3.8L ENGINE
NOTE: Before proceeding, review all WARNINGS
and CAUTIONS. (Refer to 19 - STEERING/PUMP -
WARNING)(Refer to 19 - STEERING/PUMP - CAU-
TION)
(1) Remove cap from power steering fluid reser-
voir.
(2) Using a siphon pump, remove as much power
steering fluid as possible from power steering fluid
reservoir.
(3) Raise vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE)
(4) Remove front emissions vapor canister. (Refer
to 25 - EMISSIONS CONTROL/EVAPORATIVE
EMISSIONS/VAPOR CANISTER - REMOVAL)
(5) Remove two bolts securing pressure hose rout-
ing clamps to suspension cradle crossmember and
steel reinforcement (Fig. 20).
(6) Place an oil drain pan under vehicle to catch
draining power steering fluid.
(7) Disconnect pressure hose at power steering
gear (Fig. 20).
Fig. 19 PRESSURE AND RETURN HOSES - 2.4L
1 - POWER STEERING PUMP
2 - RETURN HOSE (HEAT SLEEVE COVERED)
3 - ROUTING CLAMPS
4 - PRESSURE HOSE TUBE NUT
5 - RETURN HOSE TUBE NUT
6 - CRADLE CROSSMEMBER
7 - POWER STEERING GEAR
8 - PRESSURE HOSE
RSPUMP19-45
FLUID COOLER (Continued)
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