heater CHRYSLER VOYAGER 1996 Service Manual

DIAGNOSIS AND TESTING
ENGINE DIAGNOSISÐPERFORMANCE
CONDITION POSSIBLE CAUSES CORRECTION
ENGINE WILL NOT
CRANK OR CRANKS
SLOWLY1. Starting motor operating, but not cranking the
engine.1. Remove the starter motor. Check for broken
flywheel teeth or a broken starter motor spring.
2. Crankshaft rotation restricted. 2. Rotate the engine to check for rotational
resistance.
3. Starting circuit connections loose or corroded. 3. Clean and tighten connections.
4. Neutral safety or starter relay inoperative. 4. Check starter relay supply voltage and proper
operation of neutral safety switch (if equipped).
Replace defective parts.
5. Battery charge low. 5. Check Battery voltage. Replace battery if a
charge cannot be held.
6. No voltage to starter solenoid. 6. Check voltage to solenoid. If necessary, replace
the solenoid.
7. Solenoid or starter motor inoperative. 7. Replace starter motor.
ENGINE CRANKS, BUT
WILL NOT START, NO
SMOKE1. No fuel in supply tank. 1. Fill fuel supply.
2. Electrical fuel shutdown solenoid not operating. 2. Check for loose wires and verify that the fuel
shutdown solenoid is functioning. Check for fault
codes in the ECU.
3. Fuel injection system defective: Cranking speed
sensor. Loose connection between ECU and
harness. No power supply to the ECU. Loose
connection between injection pump and harness.3. Check for fault codes at ECU. Refer to Group 14,
Fuel System for repairs procedures.
4. Air intake or exhaust plugged. 4. Remove the obstruction.
5. Fuel filter plugged. 5. Drain fuel/water separator and replace fuel filter.
6. Excessive fuel inlet restriction. 6. Check for restriction. Correct cause.
7. Injection pump not getting fuel or fuel is aerated. 7. Check fuel flow/bleed fuel system.
8. One or more injectors worn or not operating
properly.8. Check/replace bad or improperly operating
injectors.
9. Camshaft out of time. 9. Check/correct timing chain sprocket alignment.
ENGINE HARD TO
START, OR WILL NOT
START, SMOKE FROM
EXHAUST1. Incorrect starting procedure. 1. The fuel shutoff solenoid control must be in the
run position. Ensure the proper procedure is being
used.
2. Cranking speed to slow. 2. Check the battery, starter motor and look for
loose or corroded wiring connections.
3. Cylinder head heater plugs defective. 3. Verify system is working. Verify connection
between heater plug relay and ECU. Repair/replace
inoperative parts.
4. Insufficient intake air 4. Inspect or replace air filter and check for
obstruction in air supply.
5. Air in fuel system or the fuel supply is
inadequate.5. Check the fuel flow through the filter and bleed
system. Locate and eliminate the air source.
6. Contaminated fuel. 6. Verify by operating the engine with clean fuel
from a temporary tank. Check for the presence of
gasoline. Drain and flush fuel supply tank. Replace
fuel/water separator filter.
7. Fuel screen plugged. 7. Check fuel screen.
8. One or more injectors worn or not operating
properly.8. Check/replace improperly operating injectors.
9. Injector pump out of time. 9. Check pump timing. Refer to Group 14, Fuel
System for procedure.
10. Engine compression low. 10. Check compression to identify the problem.
11. Fuel injection system defective. 11. Vacuum modulator defective causing EGR to
open in cold condition. Check for fault codes in the
ECU.
NS/GSENGINE 9 - 43

ENGINE ASSEMBLY
REMOVAL
(1) Disconnect the battery.
(2) Remove the air cleaner assembly and inlet
hose.
(3) Remove both hoses at intercooler and engine.
(4) Disconnect EGR vacuum hose.
(5) Disconnect brake booster vacuum hose.
(6) Disconnect oil pressure switch connector (Fig.
19).
(7) Disconnect Wiring harness bracket at transaxle
shift tower.
(8) Disconnect transaxle wiring at speed sensor,
crank sensor, and backup light switch.
(9) Remove both transmission shift cables at trans-
mission.
(10) Remove negative battery cable at cylinder
block (Fig. 19).
(11) Remove oil separator.
(12) Remove connectors at coolant temperature
sensor and A/C compressor.
(13) Disconnect fuel injection pump wiring connec-
tors (Fig. 19).
(14) Disconnect glow plug connectors.
(15) Disconnect electrical connector at number 1
fuel injector.
(16) Raise vehicle on hoist.
(17) Remove right side splash shield (Fig. 20).
WARNING: THE COOLANT IN A RECENTLY OPER-
ATED ENGINE IS HOT AND PRESSURIZED. USE
CARE TO PREVENT SCALDING BY HOT COOLANT.CAREFULLY RELEASE THE PRESSURE BEFORE
REMOVING THE RADIATOR DRAIN COCK AND CAP.
(18) Drain the cooling system (refer to Group 7,
Cooling).
(19) Lower vehicle.
(20) Remove Coolant pressure bottle and discon-
nect low coolant level sensor.
(21) Disconnect both heater hoses.
(22) Remove the lower radiator hose.
(23) Remove the upper radiator hose.
(24) Remove fuel line at injector pump and cap.
(25) Remove power steering reservoir and reposi-
tion.
(26) Remove upper radiator crossmember.
(27) Disconnect cooling fan module connector.
Fig. 18 Shift Cables at Rear MountFig. 19 Component Locations
Fig. 20 Right Side Splash Shield
NS/GSENGINE 9 - 53
REMOVAL AND INSTALLATION (Continued)

(3) Install cylinder head cover, torque nuts to 14.7
N´m (132 in. lbs.).
(4) Install coolant pressure tank.
(5) Install breather hose.
(6) Install generator bracket, tighten bolts to 7
N´m (4 ft. lbs.).
(7) Connect the service valves to the A/C compres-
sor ports, if equipped with air conditioning.
(8) Connect battery cable.
VALVE SPRINGSÐCYLINDER HEAD NOT
REMOVED
This procedure can be done with the engine cylin-
der head installed on the block.
REMOVAL
Each valve spring is held in place by a retainer
and a set of conical valve locks. The locks can be
removed only by compressing the valve spring.
(1) Remove the engine cylinder head cover, refer to
cylinder head cover removal in this section.
(2) Remove rocker arms assemblies for access to
each valve spring to be removed.
(3) Remove push rods. Retain the push rods, and
rocker arms assemblies in the same order and posi-
tion as removed.
(4) Inspect the springs and retainer for cracks and
possible signs of weakening.
(5) Install an air hose adaptor in the fuel injector
hole.
(6) Connect an air hose to the adapter and apply
air pressure slowly. Maintain at least 621 kPa (90psi) of air pressure in the cylinder to hold the valves
against their seats.
(7) Tap the retainer or tip with a rawhide hammer
to loosen the lock from the retainer. Use Valve Spring
Compressor Tool to compress the spring and remove
the locks.
(8) Remove valve spring and retainer.
Inspect the valve stems, especially the grooves. An
Arkansas smooth stone should be used to remove
nicks and high spots.
INSTALLATION
(1) Install valve spring and retainer.
(2) Compress the valve spring with Valve Spring
Compressor Tool and insert the valve locks. Release
the spring tension and remove the tool. Tap the
spring from side-to-side to ensure that the spring is
seated properly on the engine cylinder head.
(3) Disconnect the air hose. Remove the adaptor
from the fuel injector hole and install the fuel injec-
tor.
(4) Repeat the procedures for each remaining valve
spring to be removed.
(5) Install the push rods. Ensure the bottom end of
each rod is centered in the plunger cap seat of the
hydraulic valve tappet.
(6) Install the rocker arm assemblies, at their orig-
inal location.
(7) Tighten the rocker arm assembly nut to 106
N´m (78 ft. lbs.) torque.
(8) Install the engine cylinder head cover, refer to
cylinder head cover installation in this section.
CYLINDER HEAD
REMOVAL
(1) Disconnect the battery cable.
WARNING: DO NOT REMOVE THE CYLINDER
BLOCK DRAIN PLUGS OR LOOSEN THE RADIATOR
DRAIN COCK WITH THE SYSTEM HOT AND PRES-
SURIZED BECAUSE SERIOUS BURNS FROM THE
COOLANT CAN OCCUR.
(2) Drain the cooling system. Refer to Group 7,
Cooling.
(3) Remove wiper module. Refer to Group 8K,
Windshield Wiper Unit Removal for procedure.
(4) Remove coolant pressure bottle.
(5) Remove intercooler hose at intake manifold
(Fig. 23).
(6) Remove intercooler hose at turbocharger inter-
cooler tube.
(7) Remove the upper radiator hose.
(8) Remove water manifold.
(9) Disconnect the heater hoses and coolant pres-
sure bottle hoses.
Fig. 22 Rocker Arm Retaining Nut
NS/GSENGINE 9 - 55
REMOVAL AND INSTALLATION (Continued)

(5) Drain cooling system. Refer to Group 7, Cool-
ing System for procedure.
(6) Remove heater, and upper radiator hoses at
intake manifold.
(7) Disconnect coolant temperature sensor (Fig.
14).
(8) Remove the accessory drive belt. Refer to
Accessory Drive belt Removal and Installation in
Group 7, Cooling System for procedure.
(9) Remove fasteners attaching generator bracket
to cylinder head, and block.
(10) Remove intake manifold center support
bracket bolts (Y bracket) (Fig. 15)
(11) Disconnect fuel injector harness.(12) Remove lower intake manifold fasteners (Fig.
16). Remove the manifold from engine.
(13) Inspect and clean manifold. Refer to Cleaning
and Inspection outlined in this section for proce-
dures.
INSTALLATION
If the following items were removed, install and
torque to:
²Fuel Rail Bolts 22 N´m (200 in. lbs.)
²Engine Outlet Connector Bolts 28 N´m (250 in.
lbs.)
²Coolant Temperature Sensor 7 N´m (60 in. lbs.)
²Intake Air Temperature Sensor 28 N´m (250 in.
lbs.)
(1) Using a new intake gasket, position intake
manifold on the engine and install retaining bolts.
Fig. 13 Fuel Line Quick Disconnect
Fig. 14 Coolant Temperature SensorÐ2.4L
Fig. 15 Intake Manifold Center Support Bracket
Fig. 16 Intake Manifold Fasteners
NSEXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 7
REMOVAL AND INSTALLATION (Continued)

(16) Remove fuel rail attaching bolts and lift fuel
rail assembly from intake manifold.
(17) Separate radiator hose from thermostat hous-
ing and heater hose from heater pipe.
(18) Remove nut and washer assemblies and
remove intake manifold (Fig. 25).
(19) Inspect and clean manifold. Refer to Cleaning
and Inspection outlined in this section for proce-
dures.
INSTALLATION
(1) Position new intake manifold gaskets on cylin-
der head and install intake (cross) manifold.
(2) Install nuts and washers and tighten in sev-
eral steps in order shown in (Fig. 26) to 20 N´m (174
in. lbs.).
(3) Make sure the injector holes are clean and all
plugs have been removed.
(4) Lube injector O-ring with a drop of clean
engine oil to ease installation.
(5) Put the tip of each injector into their ports.
Push the assembly into place until the injectors are
seated in the ports.
(6) Install the fuel rail attaching bolts and torque
to 13 N´m (115 in. lbs.).(7) Install fuel supply and the vacuum crossover
tube hold-down bolt and torque to 10 N´m (95 in.
lbs.).
(8) Remove covering from lower intake manifold
and clean surface.
(9) Place intake manifold gasketswith beaded
sealant side upon lower manifold. Put air intake in
place. Install attaching fasteners and tighten in sev-
eral steps in sequence shown (Fig. 27) to 13 N´m (115
in. lbs.).
Fig. 25 Intake and Exhaust Manifolds Ð 3.0L Engine
Fig. 26 Fastener Tightening Sequence for Intake
(Cross) Manifold
11 - 10 EXHAUST SYSTEM AND INTAKE MANIFOLDNS
REMOVAL AND INSTALLATION (Continued)

(10) Connect fuel line to fuel rail (Fig. 21). Torque
hose clamps to 1 N´m (10 in. lbs.).
(11) Connect vacuum harness to air intake ple-
num.
(12) Connect and coolant temperature sensor elec-
trical connector to sensor (Fig. 21).
(13) Connect PCV and brake booster supply hose
to intake plenum.
(14) Connect automatic idle speed (AIS) motor
and throttle position sensor (TPS) electrical connec-
tors (Fig. 19).
(15) Connect vacuum vapor harness to throttle
body (Fig. 19).
(16) Install throttle cable and transaxle kickdown
linkage (Fig. 18).
(17) Install air inlet resonator hose assembly to
throttle body.
(18) Install radiator to thermostat housing hose
and heater hose to heater pipe nipple.
(19) Fill cooling system. Refer to Filling the Cool-
ing System outlined in Group 7 Cooling System for
procedure.
(20) Connect negative battery cable.
(21) With the DRB Scan Tool use ASD Fuel Sys-
tem Test to pressurize system to check for leaks.
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 MANIFOLDÐ3.0L ENGINE
REMOVAL
(1) Raise vehicle and disconnect exhaust pipe
from rear (cowl side) exhaust manifold at the flex-
joint.(2) Disconnect Oxygen Sensor lead wire at the
rear exhaust manifold (Fig. 28).
(3) Remove bolts attaching cross-over pipe to
manifold (Fig. 30).
(4) Remove rear heat shield (Fig. 29).
(5) Remove nuts attaching rear manifold to cylin-
der head and remove manifold.
(6) Lower vehicle and remove screws attaching
front heat shield to front manifold (Fig. 31).
(7) Remove bolts fastening crossover pipe to front
exhaust manifold and nuts fastening manifold to cyl-
inder head. Remove assemblies.
(8) Inspect and clean manifolds. Refer to Cleaning
and Inspection outlined in this section for proce-
dures.
INSTALLATION
Install the gaskets with the numbers 1-3-5
embossed on the top on the rear bank and those with
numbers 2-4-6 on the front (Radiator side) bank (Fig.
32).
(1) Install rear exhaust manifold and tighten
attaching nuts to 20 N´m (175 in. lbs.).
Fig. 27 Intake Plenum Tightening Sequence
Fig. 28 Disconnect Up Stream Heated Oxygen
Sensor Connection
Fig. 29 Rear Exhaust Manifold Heat Shield
NSEXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 11
REMOVAL AND INSTALLATION (Continued)

in the engine compartment next to the battery (Fig.
30). A label affixed to the underside of the PDC cover
identifies the relays and fuses in the PDC.
GENERATOR FIELDÐPCM OUTPUT
The PCM regulates the charging system voltage
within a range of 12.9 to 15.0 volts. Refer to Group
8A for Battery system information and 8C for charg-
ing system information.
AUTOMATIC SHUTDOWN RELAYÐPCM OUTPUT
The Automatic Shutdown (ASD) relay supplies bat-
tery voltage to the fuel injectors, electronic ignition
coil and the heating elements in the oxygen sensors.
A buss bar in the Power Distribution Center (PDC)
supplies voltage to the solenoid side and contact side
of the relay. The ASD relay power circuit contains a
25 amp fuse between the buss bar in the PDC and
the relay. The fuse is located in the PDC. Refer to
Group 8W, Wiring Diagrams for circuit information.
The PCM controls the relay by switching the
ground path for the solenoid side of the relay on and
off. The PCM turns the ground path off when the
ignition switch is in the Off position unless the 02
Heater Monitor test is being run. Refer to Group 25,
On-Board Diagnostics. When the ignition switch is in
the On or Crank position, the PCM monitors the
crankshaft position sensor and camshaft position sen-
sor signals to determine engine speed and ignition
timing (coil dwell). If the PCM does not receive the
crankshaft position sensor and camshaft position sen-
sor signals when the ignition switch is in the Run
position, it will de-energize the ASD relay.The ASD relay is located in the PDC (Fig. 30). A
label affixed to the underside of the PDC cover iden-
tifies the relays and fuses in the PDC.
FUEL PUMP RELAYÐPCM OUTPUT
The fuel pump relay supplies battery voltage to the
fuel pump. The fuel pump relay power circuit con-
tains a 9 amp fuse. The fuse is located in the PDC.
Refer to Group 8W, Wiring Diagrams for circuit infor-
mation.
The PCM controls the fuel pump relay by switch-
ing the ground path for the solenoid side of the relay
on and off. The PCM turns the ground path off when
the ignition switch is in the Off position. When the
ignition switch is in the On position, the PCM ener-
gizes the fuel pump. If the crankshaft position sensor
does not detect engine rotation, the PCM de-ener-
gizes the relay after approximately one second.
The fuel pump relay is located in the PDC (Fig.
30). A label affixed to the underside of the PDC cover
identifies the relays and fuses in the PDC.
STARTER RELAYÐPCM OUTPUT
Double Start Override ia a feature that prevents
the starter from operating if the engine is already
running. This feature is accomplished with software
only. There was no hardware added because of this
feature. To incorporate the unique feature of Double
Start Override, it was necessary to use the PCM
(software) to control the starter circuit. To use the
PCM it was necessary to separate the starter relay
coil ground from the park neutral switch. The starter
relay ground is now controlled through Pin 60 of the
PCM. This allows the PCM to interrupt the ground
circuit if other inputs tell it that the engine is turn-
ing. If the starter system is operating properly, it can
be assumed that the override protection is also work-
ing.
IDLE AIR CONTROL MOTORÐPCM OUTPUT
The idle air control motor is mounted on the throt-
tle body. The PCM operates the idle air control motor
(Fig. 26) or (Fig. 27) or (Fig. 28). The PCM adjusts
engine idle speed through the idle air control motor
to compensate for engine load or ambient conditions.
The throttle body has an air bypass passage that
provides air for the engine at idle (the throttle blade
is closed). The idle air control motor pintle protrudes
into the air bypass passage and regulates air flow
through it.
The PCM adjusts engine idle speed by moving the
idle air control motor pintle in and out of the bypass
passage. The adjustments are based on inputs the
PCM receives. The inputs are from the throttle posi-
tion sensor, crankshaft position sensor, coolant tem-
perature sensor, and various switch operations
Fig. 30 Power Distribution Center (PDC)
14 - 42 FUEL SYSTEMNS
DESCRIPTION AND OPERATION (Continued)

PCM. If OK, replace MAP sensor. If not OK, repair or
replace the wire harness as required.
HEATED OXYGEN SENSOR
Use an ohmmeter to test the heating element of
the oxygen sensors. Disconnect the electrical connec-
tor from each oxygen sensor. The white wires in the
sensor connector are the power and ground circuits
for the heater. Connect the ohmmeter test leads to
terminals of the white wires in the heated oxygen
sensor connector. Replace the heated oxygen sensor if
the resistance is not between 4 and 7 ohms.
KNOCK SENSOR
The engine knock sensor is affected by a number of
factors. A few of these are: ignition timing, cylinder
pressure, fuel octane, etc. The knock sensor gener-
ates an AC voltage whose amplitude increases with
the increase of engine knock. The knock sensor can
be tested with a digital voltmeter. The RMS voltage
starts at about 20mVac (at about 700 rpm) and
increases to approximately 600 mVac (5000 rpm). If
the output falls outside of this range a DTC will be
set.
CAMSHAFT AND CRANKSHAFT POSITION SENSOR
Refer to Group 8D, Ignition for Diagnosis and Test-
ing of Camshaft and Crankshaft Sensors.
ENGINE COOLANT TEMPERATURE SENSOR
(1) With the key off, disconnect wire harness con-
nector from coolant temperature sensor (Fig. 96) or
(Fig. 97) or (Fig. 98).
(2) Connect a high input impedance (digital) volt-
ohmmeter to terminals A and B (Fig. 99). The ohm-
meter should read as follows:
(a) ECT STET at normal operating temperature
around 200ÉF should read approximately 700 to
1,000 ohms.
(b) ECT STET at room temperature around 70ÉF
ohmmeter should read approximately 7,000 to
13,000 ohms.
(3) Test the resistance of the wire harness between
the PCM connector terminal 26 and the sensor har-
ness connector. Also check for continuity between
PCM connector terminal 43 and the sensor harness
connector. Refer to Group 8W, Wiring diagrams for
Fig. 96 Engine Coolant Temperature SensorÐ2.4L
Fig. 97 Engine Coolant Temperature SensorÐ3.0L
Fig. 98 Engine Coolant Temperature SensorÐ3.3/
3.8L
NSFUEL SYSTEM 14 - 61
DIAGNOSIS AND TESTING (Continued)

FUEL DELIVERY SYSTEMÐ2.5L DIESEL ENGINE
INDEX
page page
DESCRIPTION AND OPERATION
FUEL DRAIN TUBES..................... 7
FUEL FILTER/WATER SEPARATOR.......... 4
FUEL GAUGE SENDING UNIT.............. 4
FUEL HEATER RELAY.................... 8
FUEL HEATER.......................... 8
FUEL INJECTION PUMP.................. 5
FUEL INJECTORS....................... 6
FUEL SHUTDOWN SOLENOID............. 5
FUEL SYSTEM PRESSURE WARNING....... 3
FUEL TANK MODULE.................... 4
FUEL TANK............................ 3
FUEL TUBES/LINES/HOSES AND CLAMPSÐ
LOW-PRESSURE TYPE................. 6
HIGH-PRESSURE FUEL LINES............. 7
INTRODUCTION........................ 3
QUICK-CONNECT FITTINGSÐLOW PRESSURE
TYPE............................... 7
WASTEGATE (TURBOCHARGER)........... 8
DIAGNOSIS AND TESTING
AIR IN FUEL SYSTEM................... 11
FUEL HEATER RELAY TEST.............. 12
FUEL INJECTION PUMP TEST............. 12
FUEL INJECTOR SENSOR TEST........... 12
FUEL INJECTOR TEST.................. 12
FUEL SHUTDOWN SOLENOID TEST........ 13
FUEL SUPPLY RESTRICTIONS............ 13GENERAL INFORMATION................. 9
HIGH-PRESSURE FUEL LINE LEAK TEST.... 14
VISUAL INSPECTION..................... 9
WASTEGATE (TURBOCHARGER).......... 14
SERVICE PROCEDURES
AIR BLEED PROCEDURES............... 14
FUEL INJECTION PUMP TIMING........... 15
REMOVAL AND INSTALLATION
ACCELERATOR PEDAL.................. 16
AIR CLEANER ELEMENT................. 16
FUEL DRAIN TUBES.................... 16
FUEL FILTER/WATER SEPARATOR......... 16
FUEL HEATER RELAY................... 17
FUEL HEATER......................... 17
FUEL INJECTION PUMP................. 19
FUEL INJECTORS...................... 22
FUEL LEVEL SENSOR................... 18
FUEL RESERVOIR MODULE.............. 25
FUEL SHUTDOWN SOLENOID............ 23
FUEL TANK........................... 23
HIGH-PRESSURE LINES................. 26
SPECIFICATIONS
FUEL INJECTOR FIRING SEQUENCE....... 27
FUEL SYSTEM PRESSURE............... 27
FUEL TANK CAPACITY.................. 27
IDLE SPEED.......................... 27
DESCRIPTION AND OPERATION
INTRODUCTION
This Fuel Delivery section will cover components
not controlled by the PCM. For components con-
trolled by the PCM, refer to the Fuel Injection Sys-
temÐ2.5L Diesel Engine section of this group.
The fuel heater relay, fuel heater and fuel gauge
are not operated by the PCM. These components are
controlled by the ignition (key) switch. All other fuel
system electrical components necessary to operate
the engine are controlled or regulated by the PCM.
FUEL SYSTEM PRESSURE WARNING
WARNING: HIGH±PRESSURE FUEL LINES DELIVER
DIESEL FUEL UNDER EXTREME PRESSURE FROM
THE INJECTION PUMP TO THE FUEL INJECTORS.
THIS MAY BE AS HIGH AS 45,000 KPA (6526 PSI).
USE EXTREME CAUTION WHEN INSPECTING FORHIGH±PRESSURE FUEL LEAKS. INSPECT FOR
HIGH±PRESSURE FUEL LEAKS WITH A SHEET OF
CARDBOARD (Fig. 1). HIGH FUEL INJECTION
PRESSURE CAN CAUSE PERSONAL INJURY IF
CONTACT IS MADE WITH THE SKIN.
FUEL TANK
The fuel tank and tank mounting used with the
diesel powered engine is the same as used with gas-
oline powered models, although the fuel tank module
is different.
The fuel tank contains the fuel tank module and
two rollover valves. Two fuel lines are routed to the
fuel tank module. One line is used for fuel supply to
the fuel filter/water separator. The other is used to
return excess fuel back to the fuel tank.
The fuel tank module contains the fuel gauge elec-
trical sending unit.An electrical fuel pump is not
used with the diesel engine.
NS/GSFUEL SYSTEMÐ2.5L DIESEL ENGINE/2.0L GAS ENGINE 14 - 3

FUEL TANK MODULE
An electric fuel pump is not attached to the fuel
tank module for diesel powered engines. Fuel is sup-
plied by the fuel injection pump.
The fuel tank module is installed in the top of the
fuel tank (Fig. 2). The fuel tank module contains the
following components:
²Fuel reservoir
²A separate in-tank fuel filter
²Electric fuel gauge sending unit
²Fuel supply line connection
²Fuel return line connection
FUEL GAUGE SENDING UNIT
The fuel gauge sending unit is attached to the side
of the fuel pump module. The sending unit consists of
a float, an arm, and a variable resistor (track). The
track is used to send an electrical signal used for fuel
gauge operation.
As the fuel level increases, the float and arm move
up. This decreases the sending unit resistance, caus-
ing the fuel gauge on the instrument panel to read
full. As the fuel level decreases, the float and arm
move down. This increases the sending unit resis-
tance, causing the fuel gauge on the instrument
panel to read empty.
FUEL FILTER/WATER SEPARATOR
The fuel filter/water separator assembly is located
in the engine compartment near the strut tower (Fig.
3).
The combination fuel filter/water separator pro-
tects the fuel injection pump by helping to remove
water and contaminants from the fuel. Moisture col-
lects at the bottom of the filter/separator in a plastic
bowl.
The fuel filter/water separator assembly contains
the fuel filter, fuel heater element, and fuel drain
valve.
For information on the fuel heater, refer to Fuel
Heater in this group.
Refer to the maintenance schedules in Group 0 in
this manual for the recommended fuel filter replace-
ment intervals.
Fig. 1 Typical Fuel Pressure Test at Injector
Fig. 2 Fuel Tank
Fig. 3 Fuel Filter/Water Separator Location
14 - 4 FUEL SYSTEMÐ2.5L DIESEL ENGINE/2.0L GAS ENGINENS/GS
DESCRIPTION AND OPERATION (Continued)