Egr CHRYSLER VOYAGER 1996 Owners Manual
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Page 1277 of 1938

(5) Make sure the injector holes are clean and all
plugs have been removed.
(6) Lube injector O-ring with a drop of clean
engine oil to ease installation.(7) Put the tip of each injector into their ports.
Push the assembly into place until the injectors are
seated in the ports (Fig. 41).
(8) Install the fuel rail attaching bolts and torque
to 22 N´m (200 in. lbs.) (Fig. 39).
(9) Install fuel tube retaining bracket screw and
torque to 4 N´m (35 in. lbs.) (Fig. 39).
(10) Connect cam sensor and coolant temperature
sensor (Fig. 40).
(11) Remove covering on lower intake manifold
and clean surface.
(12) Place the new intake manifold gasket on
lower manifold. Put upper manifold into place and
install bolts and nuts finger tight.
NOTE: At no time should the studs be replaced
with a bolt and washer.
(13) Install the generator bracket to intake mani-
fold bolt and the cylinder head to intake manifold
strut bolts. (Do not torque.)
(14) Torque intake manifold bolts to 28 N´m (250
in. lbs.) following torque sequence in (Fig. 38).
(15) Torque generator bracket to intake manifold
bolt to 54 N´m (40 ft. lbs.).
(16) Torque the cylinder head to intake manifold
strut bolts to 54 N´m (40 ft. lbs.) (Fig. 35).
(17) Connect ground strap and MAP sensor electri-
cal connectors.
(18) Connect vacuum harness to intake plenum
(Fig. 34).
(19) Using a new gasket, connect the EGR tube
flange to the intake manifold and torque to 22 N´m
(200 in. lbs.).
(20) Clip wiring harness into the hole in the throt-
tle cable bracket.
(21) Connect the wiring connectors to the throttle
position sensor (TPS) and Automatic Idle Speed (AIS)
motor (Fig. 33).
(22) Connect vacuum harness to throttle body (Fig.
33).
(23) Install the direct ignition system (DIS) coils.
Torque fasteners to 12 N´m (105 in. lbs.) (Fig. 37).
(24) Lubricate the end of the chassis fuel tube
with 30 wt. oil. Connect fuel supply hose to chassis
fuel tube assembly. Pull back on the quick connect
fitting to ensure complete insertion (Fig. 36). (Refer
to Fuel Hoses, Clamps and Quick Connect Fittings in
Group 14 Fuel Systems).
(25) Install throttle cable. Refer to Group 14 Fuel
System for procedure.
(26) Connect fuel injector wiring harness.
(27) Install air cleaner and hose assembly.
(28) Connect negative battery cable. Fill Cooling
System. See Cooling System, Group 7.
(29) With the DRB Scan Tool use ASD Fuel Sys-
tem Test to pressurize system to check for leaks.
Fig. 42 Intake Manifold Removal and Installation
Fig. 43 Intake Manifold Gasket
Fig. 44 Intake Manifold Gasket Sealing
NSEXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 15
REMOVAL AND INSTALLATION (Continued)
Page 1278 of 1938

CAUTION: When using the ASD Fuel System Test,
The Auto Shutdown (ASD) Relay will remain ener-
gized for 7 minutes or until the ignition switch is
turned to the OFF position, or Stop All Test is
selected.
EXHAUST MANIFOLDSÐ3.3/3.8L ENGINE
REMOVAL
(1) Disconnect battery negative cable.
(2) Remove accessory drive belt. Refer to Accessory
Drive section located in Group 7 Cooling System for
procedure.
(3) Remove generator.
(4) Raise vehicle and disconnect exhaust pipe
from rear (cowl side) exhaust manifold at flex-joint.
(5) Disconnect down stream oxygen sensor connec-
tor.
(6) Lower exhaust system to gain access to rear
manifold.
(7) Separate EGR tube from rear manifold and
disconnect Heated Oxygen Sensor lead wire (Fig. 45).
(8) Remove heat shield from rear engine mount.
(9) Remove Generator/Power Steering Support
Strut (Fig. 45).
(10) Remove bolts attaching crossover pipe to
manifold (Fig. 45).
(11) Disconnect up stream oxygen sensor connec-
tor.
(12) Remove bolts attaching rear manifold to cyl-
inder head and remove manifold.
(13) Lower vehicle and remove screws attaching
front heat shield to front manifold (Fig. 46).
(14) Remove bolts fastening crossover pipe to
front exhaust manifold and nuts fastening manifold
to cylinder head. Remove assemblies (Fig. 47).
(15) Inspect and clean manifold. Refer to Cleaning
and Inspection outlined in this section for proce-
dures.
INSTALLATION
(1) Install rear exhaust manifold and tighten
attaching bolts to 23 N´m (200 in. lbs.).
(2) Install generator.
NOTE: Inspect crossover pipe fasteners for dam-
age from heat and corrosion. Replace if necessary.
(3) Using new gasket attach crossover pipe to
exhaust manifold and tighten bolts to 54 N´m (40 ft.
lbs.) and connect oxygen sensor lead (Fig. 45).
(4) Install EGR Tube and Generator/Power Steer-
ing Strut (Fig. 45).
(5) Using new gaskets install front exhaust mani-
fold and tighten attaching bolts to 23 N´m (200 in.
lbs.).(6) Attach exhaust crossover with a new gasket
and tighten fasteners to 54 N´m (40 ft. lbs.) (Fig. 47).
(7) Connect up stream oxygen sensor connector.
(8) Install exhaust system.
Fig. 45 EGR Tube, Heated Oxygen Sensor and
Generator/Power Steering Strut
Fig. 46 Heat ShieldÐFront
Fig. 47 Crossover Pipe
11 - 16 EXHAUST SYSTEM AND INTAKE MANIFOLDNS
REMOVAL AND INSTALLATION (Continued)
Page 1316 of 1938

(6) Disconnect idle air control motor and Throttle
Position Sensor (TPS) electrical connectors (Fig. 44).
(7) Remove vacuum hose harness from throttle
body and intake manifold (Fig. 45).
(8) Remove EGR tube to intake manifold flange
bolts (Fig. 46).
(9) Remove cylinder head to intake plenum strut.
(10) Disconnect electrical connector from the MAP
sensor (Fig. 47)(11) Remove engine mounted ground strap.
(12) Remove the fuel hose quick connect fitting
from the chassis tube (Fig. 48).Refer to Fuel
Hoses, Clamps and Quick Connect Fittings in
this Section.
WARNING: WRAP A SHOP TOWEL AROUND
HOSES TO CATCH ANY GASOLINE SPILLAGE.
Fig. 43 Throttle Cable Attachment
Fig. 44 Electrical and Vacuum Connection to
Throttle Body
Fig. 45 Vacuum Connections
Fig. 46 EGR TubeÐ3.3L/3.8
14 - 22 FUEL SYSTEMNS
REMOVAL AND INSTALLATION (Continued)
Page 1318 of 1938

(4) Install the fuel rail mounting bolts. Tighten
bolts to 22 N´m (200 in. lbs.) torque (Fig. 51).
(5) Install fuel tube retaining bracket screw.
Tighten screw to 4 N´m (35 in. lbs.) torque.
(6) Connect electrical connectors to camshaft posi-
tion sensor and engine coolant temperature sensor.
(7) Remove covering on lower intake manifold and
clean surface.
(8) Place intake manifold gasket on lower mani-
fold. Put upper manifold into place and install bolts
finger tight.
(9) Install the generator bracket to intake mani-
fold bolt and the cylinder head to intake manifold
strut bolts (do not tighten.)(10) Following the tightening sequence in (Fig. 50),
tighten intake manifold bolts to 28 N´m (250 in. lbs.)
torque.
(11) Tighten generator bracket to intake manifold
bolt to 54 N´m (40 ft. lbs.) torque.
(12) Tighten the cylinder head to intake manifold
strut bolts to 54 N´m (40 ft. lbs.) torque.
(13) Connect ground strap and MAP sensor electri-
cal connector.
(14) Connect vacuum harness to intake plenum.
Connect PCV system hoses.
(15) Using a new gasket, connect the EGR tube to
the intake manifold plenum. Tighten screws to 22
N´m (200 in. lbs.) torque.
(16) Connect electrical connectors to the TPS and
idle air control motor.
(17) Connect vacuum harness to throttle body.
(18) Install the direct ignition system (DIS) coils.
Tighten fasteners to 12 N´m (105 in. lbs.) torque.
(19) Install fuel hose quick connector fitting to
chassis tubes.Refer to Fuel Hoses, Clamps and
Quick Connect Fittings in this Section.Push the
fitting onto the chassis tube until it clicks into place.
Pull on the fitting to ensure complete insertion.
(20) Install throttle cable and speed control cable
(if equipped).
(21) Install air inlet resonator.
(22) Connect negative cable to battery.
CAUTION: When using the ASD Fuel System Test,
the ASD relay and fuel pump relay remain energized
for 7 minutes or until the test is stopped, or until
the ignition switch is turned to the Off position.
(23) With the ignition key in ON position, access
the DRB scan tool ASD Fuel System Test to pressur-
ize the fuel system. Check for leaks.
FUEL INJECTORÐ2.4L
The fuel rail must be removed first. Refer to Fuel
Injector Rail Removal in this section.
REMOVAL
(1) Disconnect injector wiring connector from injec-
tor.
(2) Position fuel rail assembly so that the fuel
injectors are easily accessible (Fig. 54).
(3) Rotate injector and pull injector out of fuel rail.
The clip will stay on the injector.
(4) Check injector O-ring for damage. If O-ring is
damaged, it must be replaced. If injector is reused, a
protective cap must be installed on the injector tip to
prevent damage. Replace the injector clip if it is dam-
aged.
(5) Repeat for remaining injectors.
Fig. 52 Camshaft Position Sensor Connector
Fig. 53 Fuel Rail Removal
14 - 24 FUEL SYSTEMNS
REMOVAL AND INSTALLATION (Continued)
Page 1323 of 1938

FUEL INJECTION SYSTEM
INDEX
page page
GENERAL INFORMATION
INTRODUCTION......................... 30
MODES OF OPERATION.................. 30
DESCRIPTION AND OPERATION
AIR CONDITIONING (A/C) CLUTCH RELAYÐ
PCM OUTPUT......................... 41
AIR CONDITIONING PRESSURE
TRANSDUCERÐPCM INPUT............. 33
AIR CONDITIONING SWITCH SENSEÐ
PCM INPUT........................... 33
AUTOMATIC SHUTDOWN (ASD) SENSEÐ
PCM INPUT........................... 33
AUTOMATIC SHUTDOWN RELAYÐPCM
OUTPUT............................. 42
AUTOMATIC TRANSAXLE CONTROL
MODULEÐPCM OUTPUT................ 44
BATTERY VOLTAGEÐPCM INPUT........... 33
BRAKE SWITCHÐPCM INPUT.............. 33
CAMSHAFT POSITION SENSORÐPCM INPUT . 33
CCDBUS .............................. 32
CRANKSHAFT POSITION SENSORÐPCM
INPUT............................... 35
DATA LINK CONNECTORÐPCM OUTPUT..... 44
DUTY CYCLE EVAP CANISTER PURGE
SOLENOIDÐPCM OUTPUT.............. 43
ELECTRONIC EGR TRANSDUCER
SOLENOIDÐPCM OUTPUT.............. 43
ENGINE COOLANT TEMPERATURE SENSORÐ
PCM INPUT........................... 36
FUEL INJECTORSÐPCM OUTPUT.......... 44
FUEL PUMP RELAYÐPCM OUTPUT......... 42
GENERATOR FIELDÐPCM OUTPUT......... 42
HEATED OXYGEN SENSOR (O2S SENSOR)Ð
PCM INPUT........................... 37
IDLE AIR CONTROL MOTORÐPCM OUTPUT . . 42
IGNITION COILÐPCM OUTPUT............. 45
INTAKE AIR TEMPERATURE SENSORÐPCM
INPUT (2.4L ONLY)..................... 41
KNOCK SENSORÐPCM INPUT............. 38
MALFUNCTION INDICATOR (CHECK ENGINE)
LAMPÐPCM OUTPUT.................. 46
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSORÐPCM INPUT.................. 39
POWERTRAIN CONTROL MODULE (PCM).... 32
PROPORTIONAL PURGE SOLENOID......... 43
SOLID STATE FAN RELAYÐPCM OUTPUT.... 46
SPEED CONTROL SOLENOIDSÐ
PCM OUTPUT......................... 46
SPEED CONTROLÐPCM INPUT............ 39STARTER RELAYÐPCM OUTPUT........... 42
SYSTEM DIAGNOSIS..................... 32
TACHOMETERÐPCM OUTPUT............. 47
THROTTLE BODY....................... 47
THROTTLE POSITION SENSOR (TPS)Ð
PCM INPUT........................... 40
TORQUE CONVERTER CLUTCH SOLENOIDÐ
PCM OUTPUT......................... 46
TRANSAXLE PARK/NEUTRAL SWITCHÐ
PCM INPUT........................... 40
VEHICLE SPEED AND DISTANCEÐ
PCM INPUT........................... 41
DIAGNOSIS AND TESTING
ASD AND FUEL PUMP RELAYS............. 59
CAMSHAFT AND CRANKSHAFT POSITION
SENSOR............................. 61
ENGINE COOLANT TEMPERATURE SENSOR . . 61
HEATED OXYGEN SENSOR............... 61
KNOCK SENSOR........................ 61
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSOR............................. 60
THROTTLE BODY MINIMUM AIR FLOW
CHECK PROCEDURE................... 62
THROTTLE POSITION SENSOR............ 62
VISUAL INSPECTIONÐ2.4L ENGINE......... 47
VISUAL INSPECTIONÐ3.0L ENGINE......... 52
VISUAL INSPECTIONÐ3.3/3.8L ENGINES..... 55
REMOVAL AND INSTALLATION
AIR CLEANER ELEMENT.................. 70
AUTOMATIC SHUTDOWN (ASD) RELAY...... 64
CAMSHAFT POSITION SENSOR............ 68
CRANKSHAFT POSITION SENSOR.......... 68
DOWNSTREAM OXYGEN SENSOR.......... 69
ENGINE COOLANT TEMPERATURE
SENSORÐ2.4L........................ 70
ENGINE COOLANT TEMPERATURE
SENSORÐ3.0L........................ 71
ENGINE COOLANT TEMPERATURE
SENSORÐ3.3/3.8L..................... 71
FUEL PUMP RELAY...................... 64
IDLE AIR CONTROL MOTOR............... 65
INTAKE AIR TEMPERATURE SENSORÐ2.4L . . . 72
KNOCK SENSOR........................ 70
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSORÐ2.4/3.3/3.8L.................. 66
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSORÐ3.0L........................ 66
POWERTRAIN CONTROL MODULE.......... 67
PROPORTIONAL PURGE SOLENOID VALVE . . . 66
NSFUEL SYSTEM 14 - 29
Page 1326 of 1938

IGNITION SWITCH OFF MODE
When the ignition switch is turned to the OFF
position, the following occurs:
²All outputs are turned off.
²No inputs are monitored.
²The PCM shuts down.
DESCRIPTION AND OPERATION
SYSTEM DIAGNOSIS
The PCM can test many of its own input and out-
put circuits. If the PCM senses a fault in a major
system, the PCM stores a Diagnostic Trouble Code
(DTC) in memory.
For DTC information, refer to Group 25, Emission
Control Systems. See On-Board Diagnostics.
CCD BUS
Various controllers and modules exchange informa-
tion through a communications port called the CCD
Bus. The PCM transmits the malfunction indicator
(check engine) lamp On/Off signal, engine RPM and
vehicle load information on the CCD Bus.
POWERTRAIN CONTROL MODULE (PCM)
The PCM is a digital computer containing a micro-
processor (Fig. 1). The PCM receives input signals
from various switches and sensors that are referred
to as PCM Inputs. Based on these inputs, the PCM
adjusts various engine and vehicle operations
through devices that are referred to as PCM Out-
puts.PCM Inputs:
²Air Conditioning Head Pressure
²Battery Voltage
²Brake Switch
²Camshaft Position Sensor
²Crankshaft Position Sensor
²Engine Coolant Temperature Sensor
²Heated Oxygen Sensors (Upstream and Down-
stream)
²Intake Air Temperature Sensor (2.4L only)
²Knock Sensor (execpt 3.0L)
²Manifold Absolute Pressure (MAP) Sensor
²SCI Receive
²Speed Control System Controls
²Throttle Position Sensor
²Transaxle Park/Neutral Position Switch (auto-
matic transaxle)
²Transmission Control Module
²Vehicle Speed Sensor
PCM Outputs:
²Air Conditioning Clutch Relay
²Automatic Shutdown (ASD) Relay
²Data Link Connector
²Proportional Purge Solenoid
²Electric EGR Transducer
²Fuel Injectors
²Fuel Pump Relay
²Generator Field
²Idle Air Control Motor
²Ignition Coil
²Leak Detection Pump
²Malfunction Indicator (Check Engine) Lamp
²Radiator Fan Control Module
²Speed Control Solenoids
²Tachometer Output
²Torque Converter Clutch Solenoid (3 speed
transmission)
²Transmission Control Module
Based on inputs it receives, the PCM adjusts fuel
injector pulse width, idle speed, ignition spark
advance, ignition coil dwell and canister purge oper-
ation. The PCM regulates the cooling fan, air condi-
tioning and speed control systems. The PCM changes
generator charge rate by adjusting the generator
field.
The PCM adjusts injector pulse width (air/fuel
ratio) based on the following inputs:
²Battery voltage
²Engine coolant temperature
²Exhaust gas content (oxygen sensors)
²Engine speed (crankshaft position sensor)
²Manifold absolute pressure
²Throttle position
The PCM adjusts ignition timing based on the fol-
lowing inputs.
²Barometric pressure
Fig. 1 Powertrain Control Module (PCM)
14 - 32 FUEL SYSTEMNS
GENERAL INFORMATION (Continued)
Page 1330 of 1938

The crankshaft position sensor is located in the
transaxle housing, above the vehicle speed sensor
(Fig. 10). The bottom of the sensor is positioned next
to the drive plate.The distance between the bot-
tom of sensor and the drive plate is critical to
the operation of the system. When servicing the
crankshaft position sensor, refer to the appro-
priate Multi-Port Fuel Injection Service Proce-
dures section in this Group.
2.4L
The second crankshaft counterweight has
machined into it two sets of four timing reference
notches and a 60 degree signature notch (Fig. 11).
From the crankshaft position sensor input the PCM
determines engine speed and crankshaft angle (posi-
tion).
The notches generate pulses from high to low in
the crankshaft position sensor output voltage. When
a metal portion of the counterweight aligns with the
crankshaft position sensor, the sensor output voltagegoes low (less than 0.3 volts). When a notch aligns
with the sensor, voltage spikes high (5.0 volts). As a
group of notches pass under the sensor, the output
voltage switches from low (metal) to high (notch)
then back to low.
If available, an oscilloscope can display the square
wave patterns of each voltage pulse. From the width
of the output voltage pulses, the PCM calculates
engine speed. The width of the pulses represent the
amount of time the output voltage stays high before
switching back to low. The period of time the sensor
output voltage stays high before switching back to
low is referred to as pulse width. The faster the
engine is operating, the smaller the pulse width on
the oscilloscope.
By counting the pulses and referencing the pulse
from the 60 degree signature notch, the PCM calcu-
lates crankshaft angle (position). In each group of
timing reference notches, the first notch represents
69 degrees before top dead center (BTDC). The sec-
ond notch represents 49 degrees BTDC. The third
notch represents 29 degrees. The last notch in each
set represents 9 degrees before top dead center
(TDC).
The timing reference notches are machined to a
uniform width representing 13.6 degrees of crank-
shaft rotation. From the voltage pulse width the
PCM tells the difference between the timing refer-
ence notches and the 60 degree signature notch. The
60 degree signature notch produces a longer pulse
width than the smaller timing reference notches. If
the camshaft position sensor input switches from
high to low when the 60 degree signature notch
passes under the crankshaft position sensor, the
PCM knows cylinder number one is the next cylinder
at TDC.
The crankshaft position sensor mounts to the
engine block behind the generator, just above the oil
filter (Fig. 12).
ENGINE COOLANT TEMPERATURE SENSORÐPCM
INPUT
The engine coolant temperature sensor is a vari-
able resistor with a range of -40ÉC to 129ÉC (-40ÉF to
265ÉF).
The engine coolant temperature sensor provides an
input voltage to the PCM. As coolant temperature
varies, the sensor resistance changes resulting in a
different input voltage to the PCM.
When the engine is cold, the PCM will demand
slightly richer air/fuel mixtures and higher idle
speeds until normal operating temperatures are
reached.
The engine coolant sensor is also used for cooling
fan control.
Fig. 10 Crankshaft Position Sensor LocationÐ3.0/
3.3/3.8L
Fig. 11 Timing Reference Notches
14 - 36 FUEL SYSTEMNS
DESCRIPTION AND OPERATION (Continued)
Page 1337 of 1938

(brake, park/neutral, air conditioning). Deceleration
die out is also prevented by increasing airflow when
the throttle is closed quickly after a driving (speed)
condition.
DUTY CYCLE EVAP CANISTER PURGE
SOLENOIDÐPCM OUTPUT
The duty cycle EVAP purge solenoid regulates the
rate of vapor flow from the EVAP canister to the
throttle body. The PCM operates the solenoid.
During the cold start warm-up period and the hot
start time delay, the PCM does not energize the sole-
noid. When de-energized, no vapors are purged. The
PCM de-energizes the solenoid during open loop oper-
ation.
The engine enters closed loop operation after it
reaches a specified temperature and the time delay
ends. During closed loop operation, the PCM ener-
gizes and de-energizes the solenoid 5 or 10 times per
second, depending upon operating conditions. The
PCM varies the vapor flow rate by changing solenoid
pulse width. Pulse width is the amount of time the
solenoid energizes.
A rubber boot covers the duty cycle EVAP purge
solenoid. The solenoid attaches to a bracket mounted
to the right engine mount (Fig. 31). The top of the
solenoid has the word TOP on it. The solenoid will
not operate properly unless it is installed correctly.
PROPORTIONAL PURGE SOLENOID
All vehicles use a proportional purge solenoid. The
solenoid regulates the rate of vapor flow from theEVAP canister to the throttle body. The PCM oper-
ates the solenoid.
During the cold start warm-up period and the hot
start time delay, the PCM does not energize the sole-
noid. When de-energized, no vapors are purged.
The proportional purge solenoid operates at a fre-
quency of 200 hz and is controlled by an engine con-
troller circuit that senses the current being applied
to the proportional purge solenoid and then adjusts
that current to achieve the desired purge flow. The
proportional purge solenoid controls the purge rate of
fuel vapors from the vapor canister and fuel tank to
the engine intake manifold.
ELECTRONIC EGR TRANSDUCER SOLENOIDÐPCM
OUTPUT
The electronic EGR transducer contains an electri-
cally operated solenoid and a back-pressure trans-
ducer (Fig. 33) or (Fig. 34) or (Fig. 35). The PCM
operates the solenoid. The PCM determines when to
energize the solenoid. Exhaust system back-pressure
controls the transducer.
When the PCM energizes the solenoid, vacuum
does not reach the transducer. Vacuum flows to the
transducer when the PCM de-energizes the solenoid.
When exhaust system back-pressure becomes high
enough, it fully closes a bleed valve in the trans-
ducer. When the PCM de-energizes the solenoid and
back-pressure closes the transducer bleed valve, vac-
uum flows through the transducer to operate the
EGR valve.
De-energizing the solenoid, but not fully closing the
transducer bleed hole (because of low back-pressure),
varies the strength of vacuum applied to the EGR
valve. Varying the strength of the vacuum changes
the amount of EGR supplied to the engine. This pro-
Fig. 31 Duty Cycle EVAP Purge Solenoid
Fig. 32 Proportional Purge Solenoid
NSFUEL SYSTEM 14 - 43
DESCRIPTION AND OPERATION (Continued)
Page 1338 of 1938

vides the correct amount of exhaust gas recirculation
for different operating conditions.
DATA LINK CONNECTORÐPCM OUTPUT
The data link connector provides the technician
with the means to connect the DRB scan tool to diag-
nosis the vehicle. The connector is located under the
dash (Fig. 36).
AUTOMATIC TRANSAXLE CONTROL MODULEÐ
PCM OUTPUT
The electronic automatic transaxle control module
and the PCM supply information to each other
through the CCD Bus. The information includes
engine speed and vehicle load. The PCM uses the
information when adjusting the fuel and ignition
strategy.
FUEL INJECTORSÐPCM OUTPUT
The fuel injectors are 12 ohm electrical solenoids
(Fig. 37). The injector contains a pintle that closes off
an orifice at the nozzle end. When electric current is
supplied to the injector, the armature and needle
move a short distance against a spring, allowing fuel
to flow out the orifice. Because the fuel is under high
pressure, a fine spray is developed in the shape of a
hollow cone. The spraying action atomizes the fuel,
adding it to the air entering the combustion chamber.
The injectors are positioned in the intake manifold.
Fig. 33 EGR SolenoidÐ3.3/3.8L
Fig. 34 EGR SolenoidÐ3.0L
Fig. 35 EGR SolenoidÐ2.4L
Fig. 36 Data Link Connector
14 - 44 FUEL SYSTEMNS
DESCRIPTION AND OPERATION (Continued)
Page 1348 of 1938

(13) Ensure the harness connector is securely
attached to each fuel injector.
(14) Check the oil pressure sending unit electrical
connection (Fig. 69).
(15) Check hose connections at throttle body.
(16) Check throttle body electrical connections
(Fig. 70).
(17) Check PCV hose connections (Fig. 71).
(18) Check EGR system vacuum hose connections
(Fig. 72).
(19) Check EGR tube to intake plenum connec-
tions.
(20) Check power brake booster vacuum connec-
tions.
(21) Check engine harness to main harness electri-
cal connections.
(22) Check all electronic automatic transaxle elec-
trical connections (Fig. 73).(23) Inspect the Powertrain Control Module (PCM)
40-way electrical connectors for damage or spread
Fig. 69 Oil Pressure Sending Unit Electrical
Connection
Fig. 70 Throttle Body Electrical and Vacuum Hose
Connections
Fig. 71 Positive Crankcase Ventilation (PCV) System
Fig. 72 EGR System
Fig. 73 Electronic Automatic Transaxle Electrical
Connections
14 - 54 FUEL SYSTEMNS
DIAGNOSIS AND TESTING (Continued)