2003 CHRYSLER VOYAGER Engine timing

(3) Install cover and tighten screws to 12 N´m (105
in. lbs.).
(4) If removed, install the oil pressure relief valve.
(Refer to 9 - ENGINE/LUBRICATION/OIL PRES-
SURE RELIEF VALVE - INSTALLATION)
INSTALLATION
(1) Install oil pump. (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PUMP - ASSEMBLY)
(2) Install timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION) and oil pan (Refer to 9
- ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
INTAKE MANIFOLD
DESCRIPTION
The intake system is made up of an upper and
lower intake manifold. The upper intake manifold is
made of a composite for both the 3.3L engine and for
the 3.8L engine (Fig. 117). The lower intake manifold
is common between the two engines (Fig. 121). It also
provides coolant crossover between cylinder heads
and houses the coolant thermostat (Fig. 121).
The intake manifold utilizes a compact design with
very low restriction and outstanding flow balance.
This design allows the engine to perform with a wide
torque curve while increasing higher rpm horse-
power.
If, for some reason, the molded-in vacuum ports
break, the composite manifold can be salvaged. The
vacuum ports are designed to break at the shoulder,
if overloaded. Additional material in the shoulder
area provides sufficient stock to repair. For more
information and procedure, (Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - STANDARD
PROCEDURE). Also, if the special screws that attach
the MAP sensor, power steering reservoir, throttle
cable bracket, and the EGR tube become stripped, an
oversized screw is available to repair the stripped-out
condition. For more information and procedure,
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - STANDARD PROCEDURE)
Fig. 110 Measuring Clearance Between Rotors
1 - FEELER GAUGE
2 - INNER ROTOR
3 - OUTER ROTOR
Fig. 111 Measuring Clearance Over Rotors
1 - FEELER GAUGE
2 - STRAIGHT EDGE
Fig. 112 Oil Pressure Relief Valve
1 - RELIEF VALVE
2 - SPRING
3 - RETAINER CAP
9 - 144 ENGINE 3.3/3.8LRS
OIL PUMP (Continued)
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VALVE TIMING
STANDARD PROCEDURE
STANDARD PROCEDURE - VALVE TIMING
VERIFICATION
(1) Remove front cylinder head cover and all 6
spark plugs.
(2) Rotate engine until the #2 piston is at TDC of
the compression stroke.
(3) Install a degree wheel on the crankshaft pulley.
(4) With proper adaptor, install a dial indicator
into #2 spark plug hole. Using the indicator find TDC
on the compression stroke.
(5) Position the degree wheel to zero.
(6) Remove dial indicator from spark plug hole.
(7) Place a 5.08 mm (0.200 in.) spacer between the
valve stem tip of #2 intake valve and rocker arm pad.
Allow tappet to bleed down to give a solid tappet
effect.
(8) Install a dial indicator so plunger contacts the
#2 intake valve spring retainer as nearly perpendic-
ular as possible. Zero the indicator.
(9) Rotate the engine clockwise until the intake
valve has lifted .254 mm (0.010 in.).
CAUTION: Do not turn crankshaft any further clock-
wise as intake valve might bottom and result in
serious damage.
(10) Degree wheel should read 6 degrees BTDC to
6 degrees ATDC.
STANDARD PROCEDURE - MEASURING
TIMING CHAIN WEAR
NOTE: This procedure must be performed with the
timing chain cover removed (Refer to 9 - ENGINE/
VALVE TIMING/TIMING CHAIN COVER - REMOVAL).
(1) Position a scale next to timing chain so that
any movement of chain may be measured (Fig. 132).
(2) Position a torque wrench and socket on the
camshaft sprocket attaching bolt. Apply force in the
direction of crankshaft rotation to take up slack to
the following torque:
²41 N´m (30 ft. lb.) with cylinder heads installed
²20 N´m (15 ft. lb.) with cylinder heads removed
NOTE: With torque applied to the camshaft
sprocket bolt, crankshaft should not be permitted to
move. It may be necessary to block crankshaft to
prevent rotation.
(3) Holding a measuring scale along edge of chain
links (Fig. 132).(4) Apply force in the reverse direction to the fol-
lowing torque:
²41 N´m (30 ft. lb.) with cylinder heads installed
²20 N´m (15 ft. lb.) with cylinder heads removed
(5) Measure amount of sprocket/chain movement.
(6) Install a new timing chain and sprockets if
movement exceeds 3.175 mm (1/8 in.).
TIMING CHAIN COVER
REMOVAL
(1) Disconnect negative cable from battery.
(2) Drain cooling system. (Refer to 7 - COOLING -
STANDARD PROCEDURE)
(3) Raise vehicle on hoist.
(4) Drain engine oil.
(5) Remove right wheel and inner splash shield.
(6) Remove oil pan. (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PAN - REMOVAL)
(7) Remove oil pick-up tube (Fig. 133).
(8) Remove accessory drive belt. (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL)
(9) Remove A/C compressor and set aside.
(10) Remove crankshaft vibration damper. (Refer
to 9 - ENGINE/ENGINE BLOCK/VIBRATION
DAMPER - REMOVAL)
(11) Remove radiator lower hose.
(12) Remove heater hose from timing chain cover
housing (Fig. 134) or water pump inlet tube (if
engine oil cooler equipped) (Fig. 135).
(13) Remove the right side engine mount. (Refer to
9 - ENGINE/ENGINE MOUNTING/RIGHT MOUNT
- REMOVAL)
(14) Remove idler pulley from engine bracket (Fig.
136).
(15) Remove the engine mount bracket (Fig. 136).
Fig. 132 Measuring Timing Chain Wear
1 - TORQUE WRENCH
RSENGINE 3.3/3.8L9 - 153
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(16) Remove camshaft position sensor from timing
chain cover (Fig. 136).
Fig. 133 OIL PICKUP TUBE
1 - BOLT
2 - OIL PICK-UP TUBE
3 - O-RING
Fig. 134 HEATER RETURN HOSE (Without Engine
Oil Cooler)
1 - CAP AND CLAMP (OIL COOLER EQUIPPED ONLY)
2 - HOSE ASSEMBLY - HEATER RETURN
3 - BOLT - HEATER TUBE ATTACHING
4 - BOLT - HEATER TUBE ATTACHING
Fig. 135 HEATER HOSES 3.3/3.8L (With Engine Oil
Cooler)
1 - HOSE - HEATER SUPPLY
2 - HOSE - HEATER RETURN
3 - TUBE ASSEMBLY - HEATER RETURN
4 - BOLT - TUBE ASSEMBLY
5 - BOLT - TUBE ASSEMBLY
6 - HOSE - HEATER RETURN/OIL COOLER OUTLET
Fig. 136 Engine Mount Bracket
1 - CAMSHAFT SENSOR
2 - BOLT - CAMSHAFT SENSOR
3 - BOLT - MOUNT BRACKET (VERTICAL)
4 - BRACKET - ENGINE MOUNT
5 - BOLT - MOUNT BRACKET (HORIZONTAL)
6 - PULLEY - IDLER
7 - BOLT - IDLER PULLEY
8 - SPACER - IDLER PULLEY BOLT
9 - BOLT - MOUNT BRACKET (HORIZONTAL)
9 - 154 ENGINE 3.3/3.8LRS
TIMING CHAIN COVER (Continued)
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(17) Remove the water pump for cover removal
clearance. (Refer to 7 - COOLING/ENGINE/WATER
PUMP - REMOVAL)
(18) Remove the bolt attaching the power steering
pump support strut to the front cover (Fig. 137).
(19) Remove the timing chain cover fasteners.
Remove timing chain cover (Fig. 138).
INSTALLATION
(1) Be sure mating surfaces of chain case cover
and cylinder block are clean and free from burrs.
Crankshaft oil seal must be removed to insure cor-
rect oil pump engagement.
NOTE: DO NOT USE SEALER ON COVER GASKET
(2) Position new gasket on timing cover (Fig. 138).
Adhere new gasket to chain case cover, making sure
that the lower edge of the gasket is flush to 0.5 mm
(0.020 in.) passed the lower edge of the cover.
(3) Rotate crankshaft so that the oil pump drive
flats are in the vertical position.
(4) Position oil pump inner rotor so the mating
flats are in the same position as the crankshaft drive
flats (Fig. 138).
CAUTION: Make sure the oil pump is engaged on
the crankshaft correctly or severe damage may
result.
(5) Install timing cover (Fig. 138).
(6) Install timing chain cover bolts. Tighten M8
bolts to 27 N´m (20 ft. lbs.) and M10 bolts to 54 N´m
(40 ft. lbs.) (Fig. 139).
(7) Install crankshaft front oil seal. (Refer to 9 -
ENGINE/ENGINE BLOCK/CRANKSHAFT OIL
SEAL - FRONT - INSTALLATION)
(8) Install water pump and pulley. (Refer to 7 -
COOLING/ENGINE/WATER PUMP - INSTALLA-
TION)(9) Install crankshaft vibration damper. (Refer to 9
- ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
INSTALLATION)
(10) Install engine mount bracket (Fig. 136) and
tighten M10 to 54 N´m (40 ft. lbs.), M8 bolt to 28
N´m (21 ft. lb. lbs.).
(11) Install idler pulley on engine mount bracket
(Fig. 136).
(12) Install right side engine mount. (Refer to 9 -
ENGINE/ENGINE MOUNTING/RIGHT MOUNT -
INSTALLATION)
(13) Install camshaft position sensor (Refer to 8 -
ELECTRICAL/IGNITION CONTROL/CAMSHAFT
POSITION SENSOR - INSTALLATION).
(14) Connect the heater return hose at rear of tim-
ing chain cover (Fig. 134) or at water pump inlet
tube (if engine oil cooler equipped) (Fig. 135).
(15) Connect the radiator lower hose.
(16) Install A/C compressor.
(17) Install accessory drive belt. (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION)
(18) Install oil pump pick-up tube with new
O-ring. Tighten attaching bolt to 28 N´m (250 in.
lbs.).
(19) Install oil pan. (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PAN - INSTALLATION)
(20) Install inner splash shield and right front
wheel.
(21) Fill crankcase with engine oil to proper level.
(22) Fill cooling system. (Refer to 7 - COOLING -
STANDARD PROCEDURE)
(23) Connect negative cable to battery.
Fig. 137 Power Steering Pump Strut
1 - BOLT - LOWER
2 - STRUT - P/S PUMP
3 - BOLT - UPPER
Fig. 138 Timing Chain Cover and Gasket
1 - GASKET
2 - TIMING CHAIN COVER
RSENGINE 3.3/3.8L9 - 155
TIMING CHAIN COVER (Continued)
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TIMING CHAIN AND
SPROCKETS
REMOVAL
REMOVAL - TIMING CHAIN AND CAMSHAFT
SPROCKET
(1) Disconnect negative cable from battery.
(2) Remove the timing chain cover. (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL)
(3) Rotate engine by turning crankshaft until the
timing marks are aligned as shown in (Fig. 140).
(4) Remove camshaft sprocket attaching bolt.
(5) Remove the timing chain with camshaft
sprocket.(6) Remove the crankshaft sprocket. (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT/CHAIN
AND SPROCKETS - REMOVAL)
REMOVAL - CRANKSHAFT SPROCKET
(1) Remove the timing chain. (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT/CHAIN
AND SPROCKETS - REMOVAL)
(2) Using Special Tools 8539, 5048-6, and 5048-1,
remove the crankshaft sprocket while holding the
crankshaft from turning (Fig. 141). Be careful not to
damage the crankshaft surfaces.
INSTALLATION
INSTALLATION - CRANKSHAFT SPROCKET
(1) Position the sprocket on the crankshaft (timing
mark out) with the timing slot aligned with the tim-
ing pin.
Fig. 139 TIMING CHAIN COVER BOLT LOCATIONS
1 - BOLT - M8 x 1.25 x 95 4 - BOLT - M8 x 1.25 x 80
2 - BOLT - M10 x 1.5 x 100 5 - BOLT - M8 x 1.25 x 45
3 - BOLT - M10 x 1.5 x 85
9 - 156 ENGINE 3.3/3.8LRS
TIMING CHAIN COVER (Continued)
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(2) Install sprocket using Special Tool 8452 (Fig.
142). Install sprocket until it is fully seats on the
crankshaft.(3) Install the timing chain and camshaft sprocket.
(Refer to 9 - ENGINE/VALVE TIMING/TIMING
BELT/CHAIN AND SPROCKETS - INSTALLATION)
INSTALLATION - TIMING CHAIN AND
CAMSHAFT SPROCKET
(1) Rotate crankshaft so the timing arrow is to the
12 o'clock position (Fig. 140).
NOTE: Lubricate timing chain and sprockets with
clean engine oil before installation.
(2) While holding camshaft sprocket and chain in
hand, place timing chain around the sprocket, align-
ing the plated link with the dot on the sprocket. Posi-
tion the timing arrow to the 6 o'clock position (Fig.
140).
(3) Place timing chain around crankshaft sprocket
with the plated link lined up with the dot on the
sprocket. Install camshaft sprocket into position.
(4) Use a straight edge to check alignment of tim-
ing marks.
(5) Install camshaft sprocket bolt and washer.
Tighten bolt to 54 N´m (40 ft. lbs.).
(6) Rotate crankshaft 2 revolutions and check tim-
ing mark alignment (Fig. 140). If timing marks do
not line up, remove camshaft sprocket and realign.
(7) Install the timing chain cover. (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION)
(8) Connect negative cable to battery.
Fig. 140 Timing Mark Alignment
1 - CAMSHAFT SPROCKET TIMING MARK (DOT)
2 - PLATED LINK
3 - CRANKSHAFT SPROCKET TIMING MARK (DOT)
4 - ARROWS
Fig. 141 CRANKSHAFT SPROCKET - REMOVAL
1 - SPECIAL TOOL 5048-6
2 - SPECIAL TOOL 5048-1
3 - SPECIAL TOOL 8450
4 - CRANKSHAFT SPROCKET
5 - SPECIAL TOOL 8539
Fig. 142 CRANKSHAFT SPROCKET - INSTALLATION
1 - SPECIAL TOOL 8452-3
2 - SPECIAL TOOL 8452-1
3 - CRANKSHAFT SPROCKET
4 - THRUST BEARING / WASHER
RSENGINE 3.3/3.8L9 - 157
TIMING CHAIN AND SPROCKETS (Continued)
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FUEL INJECTION
OPERATION
OPERATION - INJECTION SYSTEM
All engines used in this section have a sequential
Multi-Port Electronic Fuel Injection system. The MPI
system is computer regulated and provides precise
air/fuel ratios for all driving conditions. The Power-
train Control Module (PCM) operates the fuel injec-
tion system.
The PCM regulates:
²Ignition timing
²Air/fuel ratio
²Emission control devices
²Cooling fan
²Charging system
²Idle speed
²Vehicle speed control
Various sensors provide the inputs necessary for
the PCM to correctly operate these systems. In addi-
tion to the sensors, various switches also provide
inputs to the PCM.
The PCM can adapt its programming to meet
changing operating conditions.
Fuel is injected into the intake port above the
intake valve in precise metered amounts through
electrically operated injectors. The PCM fires the
injectors in a specific sequence. Under most operat-
ing conditions, the PCM maintains an air fuel ratio
of 14.7 parts air to 1 part fuel by constantly adjust-
ing injector pulse width. Injector pulse width is the
length of time the injector is open.
The PCM adjusts injector pulse width by opening
and closing the ground path to the injector. Engine
RPM (speed) and manifold absolute pressure (air
density) are theprimaryinputs that determine
injector pulse width.
OPERATION - MODES OF OPERATION
As input signals to the PCM change, the PCM
adjusts its response to output devices. For example,
the PCM must calculate a different injector pulse
width and ignition timing for idle than it does for
Wide Open Throttle (WOT). There are several differ-
ent modes of operation that determine how the PCM
responds to the various input signals.
There are two different areas of operation, OPEN
LOOP and CLOSED LOOP.
During OPEN LOOP modes the PCM receives
input signals and responds according to preset PCM
programming. Inputs from the upstream and down-
stream heated oxygen sensors are not monitored dur-
ing OPEN LOOP modes, except for heated oxygensensor diagnostics (they are checked for shorted con-
ditions at all times).
During CLOSED LOOP modes the PCM monitors
the inputs from the upstream and downstream
heated oxygen sensors. The upstream heated oxygen
sensor input tells the PCM if the calculated injector
pulse width resulted in the ideal air-fuel ratio of 14.7
to one. By monitoring the exhaust oxygen content
through the upstream heated oxygen sensor, the
PCM can fine tune injector pulse width. Fine tuning
injector pulse width allows the PCM to achieve opti-
mum fuel economy combined with low emissions.
For the PCM to enter CLOSED LOOP operation,
the following must occur:
(1) Engine coolant temperature must be over 35ÉF.
²If the coolant is over 35ÉF the PCM will wait 38
seconds.
²If the coolant is over 50ÉF the PCM will wait 15
seconds.
²If the coolant is over 167ÉF the PCM will wait 3
seconds.
(2) For other temperatures the PCM will interpo-
late the correct waiting time.
(3) O2 sensor must read either greater than 0.745
volts or less than 0.29 volt.
(4) The multi-port fuel injection systems has the
following modes of operation:
²Ignition switch ON (Zero RPM)
²Engine start-up
²Engine warm-up
²Cruise
²Idle
²Acceleration
²Deceleration
²Wide Open Throttle
²Ignition switch OFF
(5) The engine start-up (crank), engine warm-up,
deceleration with fuel shutoff and wide open throttle
modes are OPEN LOOP modes. Under most operat-
ing conditions, the acceleration, deceleration (with
A/C on), idle and cruise modes,with the engine at
operating temperatureare CLOSED LOOP modes.
IGNITION SWITCH ON (ZERO RPM) MODE
When the ignition switch activates the fuel injec-
tion system, the following actions occur:
²The PCM monitors the engine coolant tempera-
ture sensor and throttle position sensor input. The
PCM determines basic fuel injector pulse width from
this input.
²The PCM determines atmospheric air pressure
from the MAP sensor input to modify injector pulse
width.
When the key is in the ON position and the engine
is not running (zero rpm), the Auto Shutdown (ASD)
and fuel pump relays de-energize after approximately
14 - 18 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 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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