
FUEL PUMP
DESCRIPTION
The electric fuel pump is located inside of the fuel
pump module. A 12 volt, permanent magnet, electric
motor powers the fuel pump. The electric fuel pump
is not a separate, serviceable component.
OPERATION
Voltage to operate the electric pump is supplied
through the fuel pump relay.
Fuel is drawn in through a filter at the bottom of
the module and pushed through the electric motor
gearset to the pump outlet.
Check Valve Operation:The pump outlet con-
tains a one-way check valve to prevent fuel flow back
into the tank and to maintain fuel supply line pres-
sure (engine warm) when pump is not operational. It
is also used to keep the fuel supply line full of gaso-
line when pump is not operational. After the vehicle
has cooled down, fuel pressure may drop to 0 psi
(cold fluid contracts), but liquid gasoline will remain
in fuel supply line between the check valve and fuel
injectors.Fuel pressure that has dropped to 0
psi on a cooled down vehicle (engine off) is a
normal condition.Refer to the Fuel Pressure Leak
Down Test for more information.
The electric fuel pump is not a separate, service-
able component.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - FUEL PUMP
CAPACITY TEST
Before performing this test, verify fuel pump
pressure. Refer to Fuel Pump Pressure Test.
Use this test in conjunction with the Fuel Pres-
sure Leak Down Test.
(1) Release fuel system pressure. Refer to Fuel
Pressure Release Procedure.
(2) Disconnect fuel supply line at fuel rail. Refer to
Quick-Connect Fittings. Some engines may require
air cleaner housing removal before line disconnection.
(3) Obtain correct Fuel Line Pressure Test Adapter
Tool Hose. Tool number 6539 is used for 5/16º fuel
lines and tool number 6631 is used for 3/8º fuel lines.
(4) Connect correct Fuel Line Pressure Test
Adapter Tool Hose into disconnected fuel supply line.
Insert other end of Adaptor Tool Hose into a gradu-
ated container.
(5) Remove fuel fill cap.
(6) To activate fuel pump and pressurize system,
obtain DRBtscan tool and actuate ASD Fuel System
Test.(7) A good fuel pump will deliver at least 1/4 liter
of fuel in 7 seconds. Do not operate fuel pump for
longer than 7 seconds with fuel line disconnected as
fuel pump module reservoir may run empty.
(a) If capacity is lower than specification, but
fuel pump can be heard operating through fuel fill
cap opening, check for a kinked/damaged fuel sup-
ply line somewhere between fuel rail and fuel
pump module.
(b) If line is not kinked/damaged, and fuel pres-
sure is OK, but capacity is low, replace fuel filter/
fuel pressure regulator. The filter/regulator may be
serviced separately on certain applications. Refer
to Fuel Filter/Fuel Pressure Regulator Removal/In-
stallation for additional information.
(c) If both fuel pressure and capacity are low,
replace fuel pump module assembly. Refer to Fuel
Pump Module Removal/Installation.
DIAGNOSIS AND TESTING - FUEL PUMP
PRESSURE TEST
Use this test in conjunction with the Fuel Pump
Capacity Test, Fuel Pressure Leak Down Test and
Fuel Pump Amperage Test found elsewhere in this
group.
Check Valve Operation:The electric fuel pump
outlet contains a one-way check valve to prevent fuel
flow back into the tank and to maintain fuel supply
line pressure (engine warm) when pump is not oper-
ational. It is also used to keep the fuel supply line
full of gasoline when pump is not operational. After
the vehicle has cooled down, fuel pressure may drop
to 0 psi (cold fluid contracts), but liquid gasoline will
remain in fuel supply line between the check valve
and fuel injectors.Fuel pressure that has
dropped to 0 psi on a cooled down vehicle
(engine off) is a normal condition.When the elec-
tric fuel pump is activated, fuel pressure should
immediately(1±2 seconds) rise to specification.
All fuel systems are equipped with a fuel tank
module mounted, combination fuel filter/fuel pressure
regulator. The fuel pressure regulator is not con-
trolled by engine vacuum.
WARNING: THE FUEL SYSTEM IS UNDER CON-
STANT FUEL PRESSURE EVEN WITH THE ENGINE
OFF. BEFORE DISCONNECTING FUEL LINE AT
FUEL RAIL, THIS PRESSURE MUST BE RELEASED.
REFER TO THE FUEL SYSTEM PRESSURE
RELEASE PROCEDURE.
(1) Remove protective cap at fuel rail test port.
Connect the 0±414 kPa (0-60 psi) fuel pressure gauge
(from gauge set 5069) to test port pressure fitting on
fuel rail (Fig. 11).The DRBtIII Scan Tool along
with the PEP module, the 500 psi pressure
BR/BEFUEL DELIVERY - GASOLINE 14 - 9

(3) Rotate module until positioned as shown in
(Fig. 19) or (Fig. 20). This step must be performed to
prevent float from contacting side of fuel tank. Be
sure fuel filter/fuel pressure regulator is pointed to
drivers side of vehicle.
(4) Install Special Tool 6856 (Fig. 21) to locknut.
(5) Tighten locknut to 24± 44 N´m (18±32 ft. lbs.)
torque.
(6) Install fuel tank. Refer to Fuel Tank - All
Engines in the Removal/Installation section.
FUEL RAIL
DESCRIPTION
DESCRIPTION - 5.9L
The fuel injector rail is used to attach the fuel
injectors to the engine. It is mounted to the engine
(Fig. 22).
DESCRIPTION - 8.0L
The fuel injector rail is used to attach the fuel
injectors to the engine. The fuel rail supplies the nec-
essary fuel to each individual fuel injector and is
mounted to the lower half of the two-piece intake
manifold (Fig. 23). The metal, one-piece fuel rail is
not repairable.
OPERATION
OPERATION - 5.9L
High pressure from the fuel pump is routed to the
fuel rail. The fuel rail then supplies the necessary
fuel to each individual fuel injector.A fuel pressure test port is located on the fuel rail.
A quick-connect fitting with a safety latch clip is
used to attach the fuel line to the fuel rail.
Fig. 21 Locknut Removal/InstallationÐTYPICAL
1 - SPECIAL TOOL 6856
2 - LOCKNUT
Fig. 22 Fuel RailÐ5.9L EngineÐTypical
1 - FUEL RAIL CONNECTING HOSE
2 - FUEL RAIL
3 - MOUNTING BOLTS (4)
Fig. 23 Fuel RailÐ8.0L Engine
1 - FUEL RAIL
2 - ELECTRICAL CONNECTOR
3 - MOUNTING BOLTS (6)
4 - INTAKE MANIFOLD LOWER HALF
5 - FUEL PRESSURE TEST PORT
6 - FUEL INJECTORS (10)
14 - 14 FUEL DELIVERY - GASOLINEBR/BE
FUEL PUMP MODULE (Continued)

The fuel rail is not repairable.
CAUTION: The left and right sections of the fuel rail
are connected with a flexible connecting hose. Do
not attempt to separate the rail halves at this con-
necting hose. Due to the design of this connecting
hose, it does not use any clamps. Never attempt to
install a clamping device of any kind to the hose.
When removing the fuel rail assembly for any rea-
son, be careful not to bend or kink the connecting
hose.
OPERATION - 8.0L
High pressure from the fuel pump is routed to the
fuel rail. The fuel rail then supplies the necessary
fuel to each individual fuel injector.
A fuel pressure test port is located on the fuel rail.
A quick-connect fitting with a safety latch clip is
used to attach the fuel line to the fuel rail.
The fuel rail is not repairable.
REMOVAL
REMOVAL - 5.9L
WARNING: THE FUEL SYSTEM IS UNDER A CON-
STANT PRESSURE (EVEN WITH ENGINE TURNED
OFF). BEFORE SERVICING FUEL RAIL ASSEMBLY,
FUEL SYSTEM PRESSURE MUST BE RELEASED.
To release fuel pressure, refer to Fuel System Pres-
sure Release Procedure found in this group.
CAUTION: The left and right fuel rails are replaced
as an assembly. Do not attempt to separate the rail
halves at the connecting hose (Fig. 24). Due to the
design of this connecting hose, it does use any
clamps. Never attempt to install a clamping device
of any kind to the hose. When removing the fuel rail
assembly for any reason, be careful not to bend or
kink the connecting hose.
(1) Remove negative battery cable at battery.
(2) Remove air cleaner.
(3) Perform fuel pressure release procedure.
(4) Remove throttle body from intake manifold.
Refer to Throttle Body removal in this group.
(5) If equipped with air conditioning, remove the
A-shaped A/C compressor-to-intake manifold support
bracket (three bolts) (Fig. 25).
(6) Disconnect electrical connectors at all fuel
injectors. To remove connector refer to (Fig. 26). Push
red colored slider away from injector (1). While push-
ing slider, depress tab (2) and remove connector (3)
from injector. The factory fuel injection wiring har-ness is numerically tagged (INJ 1, INJ 2, etc.) for
injector position identification. If harness is not
tagged, note wiring location before removal.
(7) Disconnect fuel tube (line) at side of fuel rail.
Refer to Quick-Connect Fittings for procedures,
(8) Remove the remaining fuel rail mounting bolts.
(9) Gently rock and pull theleftfuel rail until the
fuel injectors just start to clear the intake manifold.
Gently rock and pull therightfuel rail until the fuel
injectors just start to clear the intake manifold.
Repeat this procedure (left/right) until all fuel injec-
tors have cleared the intake manifold.
Fig. 24 Fuel Rail AssemblyÐTypical
1 - FUEL RAIL CONNECTING HOSE
2 - FUEL RAIL
3 - MOUNTING BOLTS (4)
Fig. 25 A/C Compressor Support BracketÐTypical
1 - AIR CONDITIONING COMPRESSOR SUPPORT BRACKET
2 - MOUNTING BOLTS
BR/BEFUEL DELIVERY - GASOLINE 14 - 15
FUEL RAIL (Continued)

(10) Remove fuel rail (with injectors attached)
from engine.
(11) Remove the clip(s) retaining the injector(s) to
fuel rail (Fig. 27) or (Fig. 28).
REMOVAL - 8.0L
WARNING: THE FUEL SYSTEM IS UNDER A CON-
STANT PRESSURE EVEN WITH THE ENGINE OFF.
BEFORE SERVICING FUEL RAIL, FUEL SYSTEM
PRESSURE MUST BE RELEASED.
(1) Remove negative battery cable at battery.
(2) Remove air cleaner housing and tube.
(3) Perform fuel pressure release procedure. Refer
to Fuel Delivery System section of this group.
(4) Disconnect throttle body linkage and remove
throttle body from intake manifold. Refer to Throttle
Body removal in this group.
(5) Remove ignition coil pack and bracket assem-
bly (Fig. 29) at intake manifold and right engine
valve cover (four bolts).
(6) Remove upper half of intake manifold. Refer to
Engines for procedures.
(7) Disconnect electrical connectors at all fuel
injectors. To remove connector refer to (Fig. 30). Push
red colored slider away from injector (1). While push-
ing slider, depress tab (2) and remove connector (3)
from injector. The factory fuel injection wiring har-
ness is numerically tagged (INJ 1, INJ 2, etc.) for
injector position identification.
(8) Disconnect fuel line quick-connect fitting at
left-rear end of fuel rail. A special 3/8 inch fuel line
disconnection tool will be necessary.
Fig. 26 Remove/Install Fuel Injector Connector
Fig. 27 Fuel Injector MountingÐTypical
1 - CLIP
2 - INJECTOR
3 - FUEL RAIL
Fig. 28 Injector Retaining ClipsÐTypical Injector
1 - PLIERS
2 - INJECTOR CLIP
3 - FUEL INJECTOR
4 - FUEL RAIL
14 - 16 FUEL DELIVERY - GASOLINEBR/BE
FUEL RAIL (Continued)

(9) Remove the six fuel rail mounting bolts from
the lower half of intake manifold (Fig. 31).
(10) Gently rock and pull theleftfuel rail until
the fuel injectors just start to clear the intake mani-
fold. Gently rock and pull therightfuel rail until
the fuel injectors just start to clear the intake mani-
fold. Repeat this procedure (left/right) until all fuel
injectors have cleared the intake manifold.
(11) Remove fuel rail (with injectors attached)
from engine.
(12) Remove the clip(s) retaining the injector(s) to
fuel rail (Fig. 27) or (Fig. 28).
INSTALLATION
INSTALLATION - 5.9L
(1) Apply a small amount of engine oil to each fuel
injector o-ring. This will help in fuel rail installation.
(2) Install injector(s) and injector clip(s) to fuel
rail.
(3) Position the fuel rail/fuel injector assembly to
the injector openings on the intake manifold.
(4) Guide each injector into the intake manifold.
Be careful not to tear the injector o-ring.
Fig. 29 Ignition Coil Pack and Mounting BracketÐ
8.0L V-10 Engine
1 - COIL PACKS AND BRACKET
2 - MOUNTING BOLTS (4)
Fig. 30 Remove/Install Fuel Injector Connector
Fig. 31 Fuel Rail Mounting BoltsÐ8.0L V-10
EngineÐTypical
1 - FUEL RAIL
2 - ELECTRICAL CONNECTOR
3 - MOUNTING BOLTS (6)
4 - INTAKE MANIFOLD LOWER HALF
5 - FUEL PRESSURE TEST PORT
6 - FUEL INJECTORS (10)
BR/BEFUEL DELIVERY - GASOLINE 14 - 17
FUEL RAIL (Continued)

(5) Push therightfuel rail down until fuel injec-
tors have bottomed on injector shoulder. Push the
leftfuel rail down until fuel injectors have bottomed
on injector shoulder.
(6) Install fuel rail mounting bolts.
(7) Connect electrical connector to intake manifold
air temperature sensor.
(8) Connect electrical connectors at all fuel injec-
tors. To install connector, refer to (Fig. 26). Push con-
nector onto injector (1) and then push and lock red
colored slider (2). Verify connector is locked to injec-
tor by lightly tugging on connector.
(9) Install the A/C support bracket (if equipped).
(10) Install throttle body to intake manifold. Refer
to Throttle Body installation in this section of the
group.
(11) Install fuel tube (line) at side of fuel rail.
Refer to Quick-Connect Fittings for procedures.
(12) Install air cleaner.
(13) Connect battery cable to battery.
(14) Start engine and check for leaks.
INSTALLATION - 8.0L
(1) Apply a small amount of engine oil to each fuel
injector o-ring. This will help in fuel rail installation.
(2) Install injector(s) and injector clip(s) to fuel
rail.
NOTE: The fuel injector electrical connectors on all
10 injectors should be facing to the right (passen-
ger) side of the vehicle (Fig. 31).
(3) Position the fuel rail/fuel injector assembly to
the injector openings on the intake manifold.
(4) Guide each injector into the intake manifold.
Be careful not to tear the injector o-ring.
(5) Push therightfuel rail down until fuel injec-
tors have bottomed on injector shoulder. Push the
leftfuel rail down until fuel injectors have bottomed
on injector shoulder.
(6) Install the six fuel rail mounting bolts into the
lower half of intake manifold. Tighten bolts to 15
N´m (136 in. lbs.) torque.
(7) Connect electrical connectors at all fuel injec-
tors. To install connector, refer to (Fig. 30). Push con-
nector onto injector (1) and then push and lock red
colored slider (2). Verify connector is locked to injec-
tor by lightly tugging on connector. The injector wir-
ing harness is numerically tagged.
(8) Install upper half of intake manifold. Refer to
Engines for procedures.
(9) Connect main fuel line at fuel rail. Refer to
Quick-Connect Fittings for procedures.
(10) Install ignition coil pack and bracket assem-
bly at intake manifold and right engine valve cover
(four bolts).(11) Install throttle body to intake manifold. Refer
to Throttle Body removal in this group.
(12) Install throttle body linkage to throttle body.
(13) Install air cleaner tube and housing.
(14) Install negative battery cable at battery.
(15) Start engine and check for leaks.
FUEL TANK
DESCRIPTION
The fuel tank is constructed of a plastic material.
Its main functions are for fuel storage and for place-
ment of the fuel pump module.
OPERATION
All models pass a full 360 degree rollover test
without fuel leakage. To accomplish this, fuel and
vapor flow controls are required for all fuel tank con-
nections.
A fuel tank check valve(s) is mounted into the top
of the fuel tank (or pump module). Refer to Emission
Control System for fuel tank check valve information.
An evaporation control system is connected to the
rollover valve(s) to reduce emissions of fuel vapors
into the atmosphere. When fuel evaporates from the
fuel tank, vapors pass through vent hoses or tubes to
a charcoal canister where they are temporarily held.
When the engine is running, the vapors are drawn
into the intake manifold. Certain models are also
equipped with a self-diagnosing system using a Leak
Detection Pump (LDP). Refer to Emission Control
System for additional information.
REMOVAL
WARNING: GASOLINE POWERED ENGINES: THE
FUEL SYSTEM IS UNDER A CONSTANT PRESSURE
EVEN WITH THE ENGINE OFF. BEFORE SERVICING
THE FUEL TANK, FUEL SYSTEM PRESSURE MUST
BE RELEASED. REFER TO THE FUEL SYSTEM
PRESSURE RELEASE PROCEDURE BEFORE SER-
VICING THE FUEL TANK.
Two different procedures may be used to drain fuel
tank (lowering tank or using DRB scan tool). When
equipped with a diesel engine, the DRB scan tool
cannot be used (no electric fuel pump).
The quickest draining procedure involves lowering
the fuel tank.
Gasoline Powered Engines:As an alternative
procedure, the electric fuel pump may be activated
allowing tank to be drained at fuel rail connection.
Refer to DRB scan tool for fuel pump activation pro-
cedures. Before disconnecting fuel line at fuel rail,
release fuel pressure. Refer to the Fuel System Pres-
sure Release Procedure in this group for procedures.
14 - 18 FUEL DELIVERY - GASOLINEBR/BE
FUEL RAIL (Continued)

FUEL INJECTION - GASOLINE
TABLE OF CONTENTS
page page
FUEL INJECTION - GASOLINE
DIAGNOSIS AND TESTING
VISUAL INSPECTIONÐ5.9L ENGINES.....29
VISUAL INSPECTIONÐ8.0L ENGINE......32
SPECIFICATIONS - TORQUE - GAS FUEL
INJECTION..........................35
SPECIAL TOOLS
FUEL SYSTEM.......................35
ACCELERATOR PEDAL
REMOVAL.............................36
INSTALLATION.........................37
CRANKSHAFT POSITION SENSOR
DESCRIPTION
DESCRIPTION - 5.9L...................37
DESCRIPTION - 8.0L...................37
OPERATION
OPERATION - 5.9L....................37
OPERATION - 8.0L....................38
REMOVAL
REMOVAL - 5.9L......................38
REMOVAL - 8.0L......................39
INSTALLATION
INSTALLATION - 5.9L..................39
INSTALLATION - 8.0L..................39
FUEL PUMP RELAY
DESCRIPTION.........................40
OPERATION...........................40
REMOVAL.............................40
INSTALLATION.........................40
IDLE AIR CONTROL MOTOR
DESCRIPTION.........................40
OPERATION...........................40
REMOVAL
REMOVAL - 5.9L......................41
REMOVAL - 8.0L......................41
INSTALLATION
INSTALLATION - 5.9L..................42
INSTALLATION - 8.0L..................42
INTAKE AIR TEMPERATURE SENSOR
DESCRIPTION - 5.9L/8.0L.................42
OPERATION - 5.9L/8.0L..................42
REMOVAL
REMOVAL - 5.9L......................42
REMOVAL - 8.0L......................43
INSTALLATION
INSTALLATION - 5.9L..................43
INSTALLATION - 8.0L..................43MANIFOLD ABSOLUTE PRESSURE SENSOR
DESCRIPTION - 5.9L/8.0L.................43
OPERATION - 5.9L/8.0L..................43
REMOVAL
REMOVAL - 5.9L......................44
REMOVAL - 8.0L......................44
INSTALLATION
INSTALLATION - 5.9L..................45
INSTALLATION - 8.0L..................45
O2 SENSOR
DESCRIPTION.........................45
OPERATION...........................45
REMOVAL.............................46
INSTALLATION.........................47
PTO SWITCH
DESCRIPTION.........................47
OPERATION...........................47
THROTTLE BODY
DESCRIPTION.........................47
OPERATION...........................47
REMOVAL
REMOVAL - 5.9L......................47
REMOVAL - 8.0L......................47
INSTALLATION
INSTALLATION - 5.9L..................48
INSTALLATION - 8.0L..................49
THROTTLE CONTROL CABLE
REMOVAL.............................49
INSTALLATION.........................50
THROTTLE POSITION SENSOR
DESCRIPTION.........................50
OPERATION...........................50
REMOVAL
REMOVAL - 5.9L......................50
REMOVAL - 8.0L......................50
INSTALLATION
INSTALLATION - 5.9L..................51
INSTALLATION - 8.0L..................51
FUEL INJECTOR
DESCRIPTION.........................52
OPERATION
OPERATION.........................52
OPERATION - PCM OUTPUT............52
DIAGNOSIS AND TESTING - FUEL INJECTOR . 53
REMOVAL.............................53
INSTALLATION.........................53
14 - 28 FUEL INJECTION - GASOLINEBR/BE

(9) Inspect fuel tube quick-connect fitting-to-fuel
rail connections.
(10) Verify that hose connections to all ports of
vacuum fittings on intake manifold are tight and not
leaking.
(11) Inspect accelerator cable, transmission throt-
tle cable (if equipped) and cruise control cable con-
nections (if equipped). Check their connections to the
throttle arm of throttle body for any binding or
restrictions.
(12) If equipped with vacuum brake booster, verify
that vacuum booster hose is firmly connected to fit-
ting on intake manifold. Also check connection to
brake vacuum booster.
(13) Inspect the air cleaner inlet and air cleaner
element for dirt or restrictions.
(14) Inspect radiator grille area, radiator fins and
air conditioning condenser for restrictions.
(15) Verify that the intake manifold air tempera-
ture sensor wire connector is firmly connected to har-
ness connector (Fig. 5).
(16) Verify that MAP sensor electrical connector is
firmly connected to MAP sensor (Fig. 6). Also verify
that rubber L-shaped fitting from MAP sensor to the
throttle body is firmly connected (Fig. 7).
(17) Verify that fuel injector wire harness connec-
tors are firmly connected to injectors in the correct
order. Each harness connector is numerically tagged
with the injector number (INJ 1, INJ 2 etc.) of its
corresponding fuel injector and cylinder number.
(18) Verify harness connectors are firmly con-
nected to idle air control (IAC) motor, throttle posi-
tion sensor (TPS) and manifold absolute pressure
(MAP) sensor (Fig. 6).(19) Verify that wire harness connector is firmly
connected to the engine coolant temperature sensor
(Fig. 8).
(20) Raise and support the vehicle.
(21) Verify oxygen sensor wire connectors are
firmly connected to the sensors. Inspect sensors and
connectors for damage (Fig. 9), (Fig. 10) or (Fig. 11).
Fig. 4 PCV Valve
1 - P C V VA LV E
2 - PCV VALVE HOSE CONNECTIONS
Fig. 5 Air Temperature
1 - INTAKE MANIFOLD AIR TEMPERATURE SENSOR
2 - ELECTRICAL CONNECTOR
Fig. 6 Sensor and IAC Motor LocationÐTypical (V-8
Shown)
1 - MAP SENSOR
2 - IDLE AIR CONTROL MOTOR
3 - THROTTLE POSITION SENSOR
14 - 30 FUEL INJECTION - GASOLINEBR/BE
FUEL INJECTION - GASOLINE (Continued)