2002 CHRYSLER CARAVAN shaft

bearing housing, routes the engine oil back to the
crankcase.
The most common turbocharger failure is bearing
failure related to repeated hot shutdowns with inad-
equate ªcool-downº periods. A sudden engine shut
down after prolonged operation will result in the
transfer of heat from the turbine section of the tur-
bocharger to the bearing housing. This causes the oil
to overheat and break down, which causes bearing
and shaft damage the next time the vehicle is
started.Letting the engine idle after extended operation
allows the turbine housing to cool to normal operat-
ing temperature. The following chart should be used
as a guide in determining the amount of engine idle
time required to sufficiently cool down the turbo-
charger before shut down, depending upon the type
of driving and the amount of cargo.
TURBOCHARGER(COOL DOWN(CHART
Driving Load Turbocharger Idle Time
(in
minuetes)
Condition Temperature Before
Shut Down
Stop & Go Empty Cool Less than 1
Stop & Go Medium Warm 1
Highway
SpeedsMedium Warm 2
City Traffic Max.
GCWRWarm 3
Highway
SpeedsMax.
GCWRWarm 4
Uphill
GradeMax.
GCWRHot 5
Fig. 3 Wastegate Operation
1 - SIGNAL LINE
2 - EXHAUST BYPASS VALVE
3 - WASTEGATE
4 - EXHAUST
5 - TURBINE
6 - EXHAUST BYPASS VALVE
7 - WASTEGATE
8 - EXHAUST
9 - TURBINE
10 - SIGNAL LINE
Fig. 4 Turbocharger Oil Supply and Drain
1 - BEARINGS
2 - OIL SUPPLY (FROM ENGINE BLOCK)
3 - OIL RETURN (TO OIL PAN)
RGEXHAUST SYSTEM AND TURBOCHARGER11a-3
TURBOCHARGER SYSTEM (Continued)
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REMOVAL
The front cradle crossmember must be installed in
the design location to achieve proper front end sus-
pension alignment. If the cradle crossmember is
removed without applying reference marks on the
frame rails, align the cradle crossmember according
to the dimensions provided in this group.
NOTE: If the caged nuts in the frame rails become
damaged and cannot be reused, a replacement nut
can be obtained through MoparT.
REMOVAL
(1) Disconnect battery negative cable.
(2) Remove steering column lower cover from
instrument panel (Refer to 23 - BODY/INSTRU-
MENT PANEL/STEERING COLUMN OPENING
COVER - REMOVAL).
(3) Remove steering column cover backing plate
(Refer to 23 - BODY/INSTRUMENT PANEL/STEER-
ING COLUMN COVER BACKING PLATE - REMOV-
AL).
(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).
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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INSTALLATION
NOTE: If cradle crossmember requires replacement.
Refer to Group 2, Suspension, to transfer suspen-
sion components and Group 19, Steering, to trans-
fer steering components.
(1) Support crossmember on suitable lifting device
(Fig. 14).
(2) Position crossmember to vehicle.
(3) Loosely install bolts attaching cradle cross-
member to front frame rails.
(4) Align crossmember to previously made marks
on frame rails.
(5) Tighten bolts attaching cradle crossmember to
frame rails.
(6) Install through bolt attaching rear engine
mount to cradle crossmember (Fig. 12) and tighten to
68 N´m (50 ft. lbs.) torque.
(7) Install the rear mount heat shield (Fig. 11).
(8) Connect lower ball joints to steering knuckles
(Refer to 2 - SUSPENSION/FRONT/LOWER BALL
JOINT - INSTALLATION)
(9) Connect stabilizer bar links to ends of stabi-
lizer bar.
(10) Install bolts attaching anti-lock brake sensor
leads to cradle crossmember.
(11) Install high pressure hose to pump.
(12) Connect return hose to metal tube.
(13) Tighten hose clamp at the cradle crossmember
coupling.
(14) Remove pinch-off pliers.
(15) Position steering so front wheels are straight
ahead.
(16) Install steering column coupling to telescoping
steering gear shaft.
(17) Install clinch bolt attaching steering column
coupling to steering gear shaft.
(18) Install steering column cover backing plate
(Refer to 23 - BODY/INSTRUMENT PANEL/STEER-
ING COLUMN COVER BACKING PLATE -
INSTALLATION)
(19) Install steering column lower cover from
instrument panel (Refer to 23 - BODY/INSTRU-MENT PANEL/STEERING COLUMN OPENING
COVER - INSTALLATION).
(20) Connect battery negative cable.
FRONT CROSSMEMBER
MOUNT BUSHINGS
REMOVAL
(1) Using paint or grease pencil, mark outline of
cradle crossmember on frame rails.
(2) Loosen bolts attaching crossmember to frame
rails.
(3) Remove bolt on bushing that requires replace-
ment.
(4) Allow cradle crossmember to drop down enough
to gain clearance for bushing removal.
(5) Remove bushing from vehicle.
INSTALLATION
(1) Apply rubber lubrication or soap to replace-
ment bushing.
(2) Insert lower half of bushing into square hole in
cradle crossmember.
(3) Place upper half of bushing on top of cross-
member aligned to receive square tube protruding
upward from lower bushing half.
(4) Squeeze bushing halves together to ensure they
are properly mated.
(5) Lift cradle crossmember upward to close gap
between the bushing and frame.
(6) Verify that lower bushing is fully seated into
cradle crossmember and upper bushing.
(7) Install bolt attaching bushing and crossmember
to frame rail hand tight.
(8) Align cradle crossmember to reference marks
on frame rails.
(9) Tighten cradle crossmember to frame rails
attaching bolts to 163 N´m (120 ft. lbs.) torque.
13 - 12 FRAME & BUMPERSRS
FRONT CRADLE CROSSMEMBER (Continued)
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FUEL DELIVERY
DESCRIPTION
DESCRIPTION
The front wheel drive car uses a plastic fuel tank
located rear center of the vehicle.
The Fuel Delivery System consists of: the following
items:
²Electric fuel pump module
²Fuel filter
²Tubes/lines/hoses
²Fuel injectors
The in-tank fuel pump module contains the fuel
pump. The pump is serviced as part of the fuel pump
module. Refer to Fuel Pump Module.
The fuel filter is replaceable, it is mounted on the
outside, on top of, the fuel tank. Refer to the Main-
tenance Schedules in the Introduction section of this
manual for recommended fuel filter replacement
intervals.
DESCRIPTION - FFV REPLACEMENT PARTS
Many components in a Flexible Fuel Vehicle (FFV)
are designed to be compatible with ethanol. Always
be sure that the vehicle is serviced with correct etha-
nol compatible parts.
CAUTION: Replacing fuel system components with
non-ethanol compatible components can damage
your vehicle and may void the warranty.
OPERATION
The fuel system provides fuel pressure by an
in-tank pump module. The PCM controls the opera-
tion of the fuel system by providing battery voltage
to the fuel pump through the fuel pump relay. The
PCM requires only three inputs and a good ground to
operate the fuel pump relay. The three inputs are:²Ignition voltage
²Crankshaft Position (CKP) sensor
²Camshaft Position (CMP) sensor
DIAGNOSIS AND TESTING - FUEL DELIVERY
SYSTEM
(Refer to Appropriate Diagnostic Information)
STANDARD PROCEDURE
STANDARD PROCEDURE - FUEL SYSTEM
PRESSURE RELEASE PROCEDURE
(1) Remove Fuel Pump relay from Power Distribu-
tion Center (PDC). For location of relay, refer to label
on underside of PDC cover.
(2) Start and run engine until it stalls.
(3) Attempt restarting engine until it will no
longer run.
(4) Turn ignition key to OFF position.
(5) Return fuel pump relay to PDC.
(6) One or more Diagnostic Trouble Codes (DTC's)
may have been stored in PCM memory due to fuel
pump relay removal. The DRB IIItscan tool must be
used to erase a DTC.
STANDARD PROCEDURE - DRAINING FUEL
TANK
(1) Release fuel system pressure, refer to the Fuel
System Release Procedure in this section.
(2) Insert a 1/4 inch siphon (max. O. D. 5/16) hose
from a portable fuel siphoning tank through the fuel
filler neck opening into the fuel tank. Hose most
have a 30 degree angle cut on the end to bypass the
check valve in the end of the filler neck. Refer to the
siphoning tank's Manufacturing Instructions.
(3) Drain fuel from fuel tank into siphoning tank.
14 - 2 FUEL DELIVERYRS
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FUEL INJECTION
TABLE OF CONTENTS
page page
FUEL INJECTION
OPERATION
OPERATION - INJECTION SYSTEM.......17
OPERATION - MODES OF OPERATION....17
FUEL CORRECTION or ADAPTIVE
MEMORIES..........................19
PROGRAMMABLE COMMUNICATIONS
INTERFACE (PCI) BUS.................20
SYSTEM DIAGNOSIS..................21
SPECIFICATIONS
TORQUE............................21
SPECIAL TOOLS
FUEL...............................22
ACCELERATOR PEDAL
REMOVAL.............................22
INSTALLATION.........................23
CRANKSHAFT POSITION SENSOR
DESCRIPTION.........................23
OPERATION...........................24
REMOVAL.............................24
INSTALLATION - 2.4L....................24
ENGINE SPEED SENSOR
DESCRIPTION.........................24
OPERATION...........................25
FUEL INJECTOR
DESCRIPTION.........................25
OPERATION...........................25
REMOVAL
REMOVAL - 2.4L......................25
REMOVAL - 3.3/3.8L...................26
INSTALLATION
INSTALLATION - 2.4L..................26
INSTALLATION - 3.3/3.8L................26
FUEL PUMP RELAY
DESCRIPTION.........................27
OPERATION...........................27
IDLE AIR CONTROL MOTOR
DESCRIPTION.........................27
OPERATION...........................27
REMOVAL.............................28INSTALLATION.........................28
INLET AIR TEMPERATURE SENSOR
DESCRIPTION.........................28
OPERATION...........................28
MAP SENSOR
DESCRIPTION.........................29
OPERATION...........................29
REMOVAL
REMOVAL - 2.4L......................30
REMOVAL - 3.3/3.8L...................30
INSTALLATION
INSTALLATION - 2.4L..................30
INSTALLATION - 3.3/3.8L................30
O2 SENSOR
DESCRIPTION.........................30
OPERATION...........................31
REMOVAL
REMOVAL - UPSTREAM 1/1 - 2.4L........32
REMOVAL - UPSTREAM 1/1 - 3.3/3.8L.....32
REMOVAL - DOWNSTREAM 1/2 - 2.4/3.3/
3.8L................................32
INSTALLATION
INSTALLATION - UPSTREAM 1/1 - 2.4L.....32
INSTALLATION - UPSTREAM 1/1 - 3.3/3.8L . . 33
INSTALLATION DOWNSTREAM 2/1 -
2.4/3.3/3.8L..........................33
THROTTLE BODY
DESCRIPTION.........................33
OPERATION...........................33
REMOVAL.............................34
INSTALLATION.........................34
THROTTLE CONTROL CABLE
REMOVAL.............................34
INSTALLATION.........................34
THROTTLE POSITION SENSOR
DESCRIPTION.........................35
OPERATION...........................35
REMOVAL - 3.3/3.8L.....................35
INSTALLATION - 3.3/3.8L.................35
14 - 16 FUEL INJECTIONRS
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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. 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 position²Knock sensor
²Throttle position
²A/C switch
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
²A/C control positions
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.
²All monitored components (refer to the Emission
section for On-Board Diagnostics).
14 - 18 FUEL INJECTIONRS
FUEL INJECTION (Continued)
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The PCM compares the upstream and downstream
heated oxygen sensor inputs to measure catalytic con-
vertor efficiency. If the catalyst efficiency drops below
the minimum acceptable percentage, the PCM stores a
diagnostic trouble code in memory, after 2 trips.
During certain idle conditions, the PCM may enter
a variable idle speed strategy. During variable idle
speed strategy the PCM adjusts engine speed based
on the following inputs.
²A/C sense
²Battery voltage
²Battery temperature or Calculated Battery Tem-
perature
²Engine coolant temperature
²Engine run time
²Inlet/Intake air temperature
²Vehicle mileage
ACCELERATION MODE
This is a CLOSED LOOP mode. The PCM recog-
nizes an abrupt increase in Throttle Position sensor
output voltage or MAP sensor output voltage as a
demand for increased engine output and vehicle
acceleration. The PCM increases injector pulse width
in response to increased fuel demand.
²Wide Open Throttle-open loop
DECELERATION MODE
This is a CLOSED LOOP mode. During decelera-
tion the following inputs are received by the PCM:
²A/C sense
²Battery voltage
²Inlet/Intake air temperature
²Engine coolant temperature
²Crankshaft position (engine speed)
²Exhaust gas oxygen content (upstream heated
oxygen sensor)
²Knock sensor
²Manifold absolute pressure
²Throttle position sensor
²IAC motor (solenoid) control changes in response
to MAP sensor feedback
The PCM may receive a closed throttle input from
the Throttle Position Sensor (TPS) when it senses an
abrupt decrease in manifold pressure. This indicates a
hard deceleration (Open Loop). In response, the PCM
may momentarily turn off the injectors. This helps
improve fuel economy, emissions and engine braking.
WIDE-OPEN-THROTTLE MODE
This is an OPEN LOOP mode. During wide-open-
throttle operation, the following inputs are used by
the PCM:
²Inlet/Intake air temperature
²Engine coolant temperature
²Engine speed
²Knock sensor²Manifold absolute pressure
²Throttle position
When the PCM senses a wide-open-throttle condi-
tion through the Throttle Position Sensor (TPS) it de-
energizes the A/C compressor clutch relay. This
disables the air conditioning system and disables
EGR (if equipped).
The PCM adjusts injector pulse width to supply a
predetermined amount of additional fuel, based on
MAP and RPM.
IGNITION SWITCH OFF MODE
When the operator turns the ignition switch to the
OFF position, the following occurs:
²All outputs are turned off, unless 02 Heater
Monitor test is being run. Refer to the Emission sec-
tion for On-Board Diagnostics.
²No inputs are monitored except for the heated
oxygen sensors. The PCM monitors the heating ele-
ments in the oxygen sensors and then shuts down.
FUEL CORRECTION or ADAPTIVE MEMORIES
DESCRIPTION
In Open Loop, the PCM changes pulse width with-
out feedback from the O2 Sensors. Once the engine
warms up to approximately 30 to 35É F, the PCM
goes into closed loopShort Term Correctionand
utilizes feedback from the O2 Sensors. Closed loop
Long Term Adaptive Memoryis maintained above
170É to 190É F unless the PCM senses wide open
throttle. At that time the PCM returns to Open Loop
operation.
OPERATION
Short Term
The first fuel correction program that begins func-
tioning is the short term fuel correction. This system
corrects fuel delivery in direct proportion to the read-
ings from the Upstream O2 Sensor.
The PCM monitors the air/fuel ratio by using the
input voltage from the O2 Sensor. When the voltage
reaches its preset high or low limit, the PCM begins
to add or remove fuel until the sensor reaches its
switch point. The short term corrections then begin.
The PCM makes a series of quick changes in the
injector pulse-width until the O2 Sensor reaches its
opposite preset limit or switch point. The process
then repeats itself in the opposite direction.
Short term fuel correction will keep increasing or
decreasing injector pulse-width based upon the
upstream O2 Sensor input. The maximum range of
authority for short term memory is 25% (+/-) of base
pulse-width. Short term is violated and is lost when
ignition is turned OFF.
RSFUEL INJECTION14-19
FUEL INJECTION (Continued)
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INSTALLATION
(1) Position accelerator pedal assembly on dash
panel. Install retaining nuts. Tighten retaining nuts
to 12 N´m (105 in. lbs.) torque (Fig. 3).
(2) From inside the vehicle, hold up the pedal and
install the throttle cable and pedal retainer in the
upper end of the pedal lever (Fig. 2).
(3) From the engine compartment, hold the throt-
tle body lever in the wide open position and install
the throttle cable (Fig. 1).
CRANKSHAFT POSITION
SENSOR
DESCRIPTION
The 2.4L crankshaft sensor is located on the rear
of the engine near the accessory drive belt (Fig. 4).
The 3.3/3.8L crankshaft sensor is located on the rear
of the transmission housing, above the differential
housing (Fig. 5). The bottom of the sensor is posi-
tioned next to the drive plate.
Fig. 2 CABLE CLIP
Fig. 3 ACCELERATOR PEDAL
Fig. 4 CRANKSHAFT SENSOR 2.4L
Fig. 5 CRANKSHAFT SENSOR 3.3/3.8L
RSFUEL INJECTION14-23
ACCELERATOR PEDAL (Continued)
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