Fuel tank CHRYSLER VOYAGER 1996 Workshop Manual
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Page 1309 of 1938

(3) Fold tangs on regulator retainer over tabs on
housing.
FUEL PUMP INLET STRAINER
REMOVAL
(1) Remove fuel pump module. Refer to Fuel Pump
Module Removal in this section.
(2) Using a thin straight blade screwdriver, pry
back the locking tabs on fuel pump reservoir and
remove the strainer (Fig. 20).
(3) Remove strainer O-ring from the fuel pump
reservoir body.
(4) Remove any contaminants in the fuel tank by
washing the inside of the fuel tank.
INSTALLATION
(1) Lubricate the strainer O-ring with clean engine
oil.
(2) Insert strainer O-ring into outlet of strainer so
that it sits evenly on the step inside the outlet.
(3) Push strainer onto the inlet of the fuel pump
reservoir body. Make sure the locking tabs on thereservoir body lock over the locking tangs on the
strainer.
(4) Install fuel pump module. Refer to Fuel Pump
Module Installation in this section.
FUEL LEVEL SENSOR
REMOVAL
Remove fuel pump module. Refer to Fuel Pump
Module in this section.
(1) Depress retaining tab and remove the fuel
pump/level sensor connector from theBOTTOMof
the fuel pump module electrical connector (Fig. 21).
NOTE: The pump module harness on TOP of flange
is not serviceable or removable.
(2) Pull off blue locking wedge (Fig. 22).
(3) Using a small screwdriver lift locking finger
away from terminal and push terminal out of connec-
tor (Fig. 23).
Fig. 19 Fuel Pressure Regulator O-rings
Fig. 20 Inlet Strainer Removal
Fig. 21 Fuel Pump/Level Sensor Electrical
Connector
Fig. 22 Wire Terminal Locking Wedge
NSFUEL SYSTEM 14 - 15
REMOVAL AND INSTALLATION (Continued)
Page 1311 of 1938

(7) Install fuel pump module. Refer to Fuel Pump
Module in this section.
FUEL TANK
WARNING: RELEASE FUEL SYSTEM PRESSURE
BEFORE SERVICING FUEL SYSTEM COMPONENTS.
SERVICE VEHICLES IN WELL VENTILATED AREAS
AND AVOID IGNITION SOURCES. NEVER SMOKE
WHILE SERVICING THE VEHICLE.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove fuel filler cap and perform Fuel Sys-
tem Pressure Release procedure.
(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.
(6) Disconnect both the fuel fill and fuel vent rub-
ber hoses at the fuel tank.(7) Disconnect fuel supply lines from the steel sup-
ply line.
The fuel pump module electrical connector
has a retainer that locks it in place.
(8) Slide fuel pump module electrical connector
lock to unlock (Fig. 29).
(9) Push down on connector retainer (Fig. 30) and
pull connector off module.
(10) Use a transmission jack to support fuel tank.
Remove bolts from fuel tank straps.
(11) Lower tank slightly. Carefully remove filler
hose from tank.
(12) Lower the fuel tank. Disconnect pressure
relief/rollover valve hose at the front of tank. Remove
clamp and remove fuel filler tube vent hose. Remove
fuel tank from vehicle.
Fig. 28 Installation Channel
Fuel Tank
Fig. 29 Fuel Line Retainers and Pump Connector
Lock
Fig. 30 Pump Module Connector Retainer and Lock
NSFUEL SYSTEM 14 - 17
REMOVAL AND INSTALLATION (Continued)
Page 1312 of 1938

INSTALLATION
(1) Position fuel tank on transmission jack. Con-
nect pressure relief/rollover valve hose. Connect fuel
filler tube vent hose and replace clamp.
(2) Raise tank into position and carefully work
filler tube into 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.
(4) Tighten strap bolts to 54 N´m (40 ft. lbs.)
torque. Remove transmission jack.
(5) Tighten filler hose clamp to 3.3 N´m (30 in.
lbs.).
CAUTION: Ensure straps are not twisted or bent
before or after tightening strap nuts.
(6) Connect fuel pump/module electrical connector.
Place retainer in locked position.
(7) Lubricate the fuel supply line with clean 30
weight engine oil, install the quick connect fuel fit-
ting. Refer to Tube/Fitting Assembly in the Fuel
Delivery section of this Group.
(8) Attach filler line to filler tube. Pull on connec-
tor to make sure of connection.
(9) Fill fuel tank, replace cap, and connect battery
negative cable.
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.
(10) Use the DRB scan tool ASD Fuel System Test
to pressurize the fuel system. Check for leaks.
FUEL INJECTOR RAILÐ2.4L
REMOVAL
(1) Perform fuel system pressure release procedure
before servicing or starting repairs.Refer to
Fuel System Pressure Release Procedure in this sec-
tion.
(2) Disconnect negative cable from battery.
(3) Remove air cleaner inlet hose from throttle
body.
(4) Remove throttle cable and speed control cable
(if equipped) from throttle lever.
(5) Remove throttle cables from bracket by com-
pressing retaining tabs.
(6) Remove connector from throttle position sensor.
(7) Remove connector from idle air control motor.
(8) Remove vacuum lines from intake plenum fit-
tings (Fig. 31) and (Fig. 32).(9) Remove connector from intake air temperature
sensor (Fig. 32).
(10) Remove connector from MAP sensor (Fig. 33).
(11) Remove fuel hose quick connect fitting from
the chassis tube (Fig. 34).Refer to Fuel Hoses,
Clamps and Quick Connect Fittings in this Sec-
tion.Place a shop towel under the connections to
absorb any fuel spilled from the fitting.
Fig. 31 Vacuum Fitting on Rear of Intake Manifold
Fig. 32 Electrical and Vacuum Connections
14 - 18 FUEL SYSTEMNS
REMOVAL AND INSTALLATION (Continued)
Page 1322 of 1938

SPECIFICATIONS
TORQUE
DESCRIPTION TORQUE
Fuel Pump Module Locknut.....58N´m(43ft.lbs.)
Fuel Tank Strap Bolts.........54N´m(40ft.lbs.)
Fuel Rail BoltsÐ2.4L........22N´m(200 in. lbs.)
Fuel Rail BoltsÐ3.0L.........13N´m(115in.lbs.)
Fuel Rail BoltsÐ3.3/3.8L.......10N´m(95in.lbs.)
Fuel Tube Holddown BoltsÐ3.0L..........22N´m
(200 in. lbs.)
Fuel Tube Holddown Screw......4N´m(35in.lbs.)
Intake Manifold BoltsÐ2.4L . . .22 N´m (200 in. lbs.)
Intake Manifold BoltsÐ3.0L . . .13 N´m (115 in. lbs.)
Intake Manifold BoltsÐ3.3/3.8L...........28N´m
(250 in. lbs.)
Accelerator Pedal to Dash Nuts...........12N´m
(105 in. lbs.)
FUEL TANK CAPACITY
Vehicle Liters U.S. Gallons
NS 75.O 20
Nominal refill capacities are shown. A variation may be
observed from vehicle to vehicle due to manufacturing
tolerance and refill procedure.
14 - 28 FUEL SYSTEMNS
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 1369 of 1938

FUEL SYSTEMÐ2.5L DIESEL ENGINE/2.0L GAS ENGINE
CONTENTS
page page
FUEL DELIVERY SYSTEMÐ2.0L ENGINE.... 28
FUEL DELIVERY SYSTEMÐ2.5L DIESEL
ENGINE.............................. 3
FUEL INJECTION SYSTEMÐ2.0L ENGINE . . . 32FUEL INJECTION SYSTEMÐ2.5L DIESEL
ENGINE............................. 43
GENERAL INFORMATION.................. 1
GENERAL INFORMATION
INDEX
page page
GENERAL INFORMATION
FUEL REQUIREMENTSÐ2.0L ENGINE....... 2
FUEL REQUIREMENTSÐ2.5L DIESEL........ 2GASOLINE/OXYGENATE BLENDS........... 2
INTRODUCTIONÐ2.0L ENGINE............. 2
INTRODUCTIONÐ2.5L DIESEL............. 1
GENERAL INFORMATION
INTRODUCTIONÐ2.5L DIESEL
Certain components of the fuel system on the 2.5L
diesel engine are controlled by the Bosch Engine con-
troller which is a Powertrain Control Module (PCM).
Refer to Powertrain Control Module in the Fuel
Injection SystemÐ2.5L Diesel Engine section of this
group for a list of items controlled by the PCM. The
Body Control Module (BCM) is mounted to a bracket
located inside the vehicle under the dashpanel to the
left of the steering column (Fig. 1). The PCM is
mounted at the base of the center console in front of
the Air Bag Module. (Fig. 2).
TheFuel Systemconsists of: the fuel tank, fuel
injection pump (engine mounted), fuel filter/water
separator, fuel tank module, electrical fuel gauge
sending unit, glow plugs, glow plug relay, PCM, and
all the electrical components that control the fuel
system. It also consists of fuel tubes/lines/hoses and
fittings, vacuum hoses, and fuel injector(s).
AFuel Return System.A separate fuel return
system is used. This will route excess fuel: from the
fuel injectors; through individual injector drain
tubes; through the fuel injection pump overflow
valve; and back to the fuel tank through a separate
fuel line.TheFuel Tank Assemblyconsists of: the fuel
tank, two pressure relief/rollover valves, fuel filler
tube, fuel tank module containing a fuel gauge send-
ing unit, and a pressure-vacuum filler cap.
Fig. 1 BCM Location
NS/GSFUEL SYSTEMÐ2.5L DIESEL ENGINE/2.0L GAS ENGINE 14 - 1
Page 1371 of 1938

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
Page 1372 of 1938

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)
Page 1374 of 1938

Actual electric fuel timing (amount of advance) is
accomplished by the fuel timing solenoid mounted to
the bottom of the injection pump (Fig. 5). Fuel timing
will be adjusted by the PCM, which controls the fuel
timing solenoid.
An overflow valve is attached into the fuel return
line at the rear of the fuel injection pump (Fig. 4).
This valve serves two purposes. One is to ensure that
a certain amount of residual pressure is maintained
within the pump when the engine is switched off.
This will prevent the fuel timing mechanism within
the injection pump from returning to its zero posi-
tion. The other purpose is to allow excess fuel to be
returned to the fuel tank through the fuel return
line. The pressure values within this valve are preset
and can not be adjusted.
The fuel injection pump supplies high±pressure
fuel of approximately 45,000 kPa (6526 psi) to each
injector in precise metered amounts at the correct
time.
For mechanical injection pump timing, refer to
Fuel Injection Pump Timing in the Service Proce-
dures section of this group.
FUEL INJECTORS
Fuel drain tubes (Fig. 6) are used to route excess
fuel back to the overflow valve (Fig. 4) at the rear of
the injection pump. This excess fuel is then returned
to the fuel tank through the fuel return line.
The injectors are connected to the fuel injection
pump by the high± pressure fuel lines. A separate
injector is used for each of the four cylinders. An
injector containing a sensor (Fig. 7) is used on thecylinder number one injector. This injector is called
instrumented injector #1 or needle movement sensor.
It is used to tell the PCM when the #1 injector's
internal spring-loaded valve seat has been forced
open by pressurized fuel being delivered to the cylin-
der, which is at the end of its compression stroke.
When the instrumented injector's valve seat is force
open, it sends a small voltage spike pulse to the
PCM. This tells the PCM that the engine is at TDC
on the number one cylinder. It is not used with the
other three injectors.
Fuel enters the injector at the fuel inlet (top of
injector) and is routed to the needle valve bore. When
fuel pressure rises to approximately 15,000±15,800
kPa (2175±2291 psi), the needle valve spring tension
is overcome. The needle valve rises and fuel flows
through the spray holes in the nozzle tip into the
combustion chamber. The pressure required to lift
the needle valve is the injector opening pressure set-
ting. This is referred to as the ªpop-offº pressure set-
ting.
Fuel pressure in the injector circuit decreases after
injection. The injector needle valve is immediately
closed by the needle valve spring and fuel flow into
the combustion chamber is stopped. Exhaust gases
are prevented from entering the injector nozzle by
the needle valve.
A copper washer (gasket) is used at the base of
each injector (Fig. 7) to prevent combustion gases
from escaping.
Fuel injector firing sequence is 1±3±4±2.
FUEL TUBES/LINES/HOSES AND CLAMPSÐLOW-
PRESSURE TYPE
Also refer to the proceeding section on Quick±Con-
nect Fittings.
Inspect all hose connections such as clamps, cou-
plings and fittings to make sure they are secure andFig. 6 Fuel Injectors and Drain Tubes
Fig. 7 Fuel Injector Sensor
14 - 6 FUEL SYSTEMÐ2.5L DIESEL ENGINE/2.0L GAS ENGINENS/GS
DESCRIPTION AND OPERATION (Continued)
Page 1375 of 1938

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 or a
quick±connect fitting. Replace complete line/tube as
necessary.
Avoid contact of any fuel tubes/hoses with other
vehicle components that could cause abrasions or
scuffing. Be sure that the fuel lines/tubes are prop-
erly routed to prevent pinching and to avoid heat
sources.
The lines/tubes/hoses are of a special construction.
If it is necessary to replace these lines/tubes/hoses,
use only original equipment type.
The hose clamps used to secure the rubber hoses
are of a special rolled edge construction. This con-
struction is used to prevent the edge of the clamp
from cutting into the hose. Only these rolled edge
type clamps may be used in this system. All other
types of clamps may cut into the hoses and cause
fuel leaks.
Where a rubber hose is joined to a metal tube
(staked), do not attempt to repair. Replace entire
line/tube assembly.
Use new original equipment type hose clamps.
Tighten hose clamps to 2 N´m (20 in. lbs.) torque.
QUICK-CONNECT FITTINGSÐLOW PRESSURE
TYPE
Different types of quick-connect fittings are used to
attach various fuel system components. These are: a
single-tab type, a two-tab type or a plastic retainer
ring type (Fig. 8). Refer to Quick-Connect Fittings in
the Removal/Installation section for more informa-
tion.
CAUTION: The interior components (o-rings, spac-
ers) of quick-connect fitting are not serviced sepa-
rately, but new pull tabs are available for some
types. Do not attempt to repair damaged fittings or
fuel lines/tubes. If repair is necessary, replace the
complete fuel tube assembly.
HIGH-PRESSURE FUEL LINES
CAUTION: The high±pressure fuel lines must be
held securely in place in their holders. The lines
cannot contact each other or other components. Do
not attempt to weld high±pressure fuel lines or to
repair lines that are damaged. Only use the recom-
mended lines when replacement of high±pressure
fuel line is necessary.
High±pressure fuel lines deliver fuel under pres-
sure of up to approximately 45,000 kPa (6526 PSI)
from the injection pump to the fuel injectors. Thelines expand and contract from the high±pressure
fuel pulses generated during the injection process. All
high±pressure fuel lines are of the same length and
inside diameter. Correct high±pressure fuel line
usage and installation is critical to smooth engine
operation.
WARNING: USE EXTREME CAUTION WHEN
INSPECTING FOR HIGH±PRESSURE FUEL LEAKS.
INSPECT FOR HIGH±PRESSURE FUEL LEAKS WITH
A SHEET OF CARDBOARD. HIGH FUEL INJECTION
PRESSURE CAN CAUSE PERSONAL INJURY IF
CONTACT IS MADE WITH THE SKIN.
FUEL DRAIN TUBES
These rubber tubes are low±pressure type.
Some excess fuel is continually vented from the
fuel injection pump. During injection, a small amount
of fuel flows past the injector nozzle and is not
injected into the combustion chamber. This fuel
drains into the fuel drain tubes (Fig. 9) and back to
the tee banjo fitting, which is connected to the same
line as the overflow valve, which allows a variable
quantity to return to the fuel tank. The overflow
valve is calibrated to open at a preset pressure.
Excess fuel not required by the pump to maintain the
minimum pump cavity pressure is then returned
through the overflow valve and on to the fuel tank
through the fuel return line.
Fig. 8 Plastic Retainer Ring-Type Fitting
NS/GSFUEL SYSTEMÐ2.5L DIESEL ENGINE/2.0L GAS ENGINE 14 - 7
DESCRIPTION AND OPERATION (Continued)