fuel cap DODGE RAM 2003 Service Owner's Guide

(2) Lower engine into the engine compartment and
install the engine the engine mount through bolts
and nuts.
(3) Tighten the mount through bolts and nuts to
88 N-m (65 ft-lbs) torque.
(4) Remove the engine lifting device (Tool 9009).
(5) Check cylinder head capscrew length and
install into cylinder head.
(6) Torque alternately to 70 N-m (52 ft-lbs). Torque
alternately to 105 N-m (77 ft-lbs). Rotate 90 degrees.
(7) Install rocker housing. Torque to 24 N-m (18 ft-
lbs). Refer to Section 9 Rocker Housing Installation
(8) Replace injector o-ring and sealing washer on
injectors #5 and #6. Install injectors and alternately
tighten hold-down capscrews to 10 N-m (89 in-lbs).
(9) Install fuel connector tube and fuel connector
tube nut. Torque to 50 N-m (37 ft-lb). 10.
(10) Install #5 and #6 high pressure fuel lines. Fol-
low correct torque sequence per section 14. Torque
fuel line fittings to 30 N-m (22 ft-lb). Torque brace
capscrew to 24 N-m (18 ft-lb).
(11) Install rear engine lift bracket. Torque to 77
N-m (57 ft-lb).
(12) Install push tubes, rocker arms, and pedestals
for cylinders #4, #5, and #6. Torque the mounting
bolts to 36 N-m (27 ft-lbs).
(13) Reset valve lash on cylinders #4, #5, and #6.
Torque adjusting nuts to 24 N-m (18 ft-lbs).
(14) Install cylinder head cover. Torque to 24 N-m
(18 ft-lbs).(Refer to 9 - ENGINE/CYLINDER HEAD -
INSTALLATION).
(15) Connect breather tube and lube oil drain tube
to breather housing. Install breather housing. Torque
capscrews to 24 N-m (18 ft-lbs)
(16) Connect fuel supply and return hoses.
(17) Connect ECM ground to hydroform screw.
Connect ECM power connector.
(18) Install the APPS cable(s) to the APPS. Install
the throttle linkage cover.
(19) Install the power steering pump.
(20) Install the damper and speed indicator ring.
Torque to 40 N-m (30 ft-lb) plus 60 degrees.
(21) Connect the engine block heater connection.
(22) Connect the A/C compressor and pressure sen-
sor connectors
(23) Install the charge air cooler and a/c condenser
(if equipped). Install and tighten the charge air
cooler mounting bolts to 2 N-m (17 in-lbs).
(24) Connect the charge air cooler piping. Torque
all clamps to 8 N-m (72 in-lbs).
(25) Connect the a/c refrigerant lines to the a/c
condenser (if equipped).
(26) Install the radiator upper support panel.
(27) Install radiator.
(28) Connect the transmission quick-connect oil
cooler lines.(29) Raise vehicle.
(30) Connect a/c compressor suction/discharge hose
(if equipped).
(31) Install the radiator lower hose and clamps.
(32) Install the battery negative cables to the
engine block on the driver and passenger side.
(33) Install the transmission adapter with a new
camshaft rectangular ring seal. Torque to 77 N-m (57
ft-lb).
(34) Install the flywheel/flexplate. Torque to 137
N-m (101 ft-lb).
(35) Install the starter motor. Torque to 43 N-m
(32 ft-lb). (Refer to 8 - ELECTRICAL/STARTING/
STARTER MOTOR - INSTALLATION).
(36) Connect engine to vehicle harness connectors.
(37) Install transmission and transfer case (if
equipped).
(38) Connect the exhaust pipe to the turbocharger
elbow.
(39) Connect the transmission auxiliary oil cooler
lines (if equipped).
(40) Lower the vehicle.
(41)
Connect the heater core supply and return hoses.
(42) Install the cooling fan and upper fan shroud
at the same time. (Refer to 7 - COOLING/ENGINE/
RADIATOR FAN - INSTALLATION).
(43) Install the coolant recovery bottle.
(44) Install the windshield washer bottle.
(45) Install the upper radiator hose and clamps.
(46) Raise vehicle.
(47) Connect electronically controlled fan drive
wire harness. Install lower radiator fan shroud.
(48) Change oil filter and install new engine oil.
(49) Fill the cooling system with coolant. (Refer to
7 - COOLING - STANDARD PROCEDURE).
(50) Connect grid heater harness at grid heater
relays.
(51) Connect electrical connections to rear of alter-
nator.
(52) Start the engine and inspect for engine oil,
coolant, and fuel leaks.
INSTALLATIONÐCRANKCASE BREATHER
(1) Install a new o-ring onto the breather element.
(2) Lubricate o-ring and install into cylinder head
cover. Torque capscrews to 10 N´m (89 in. lbs.).
(3) Connect breather tube and lube oil drain tube.
(4) Install breather cover (Fig. 4). Torque to 24
N´m (18 ft. lbs.)
(5) Install oil fill cap.
9 - 292 ENGINE 5.9L DIESELDR
ENGINE 5.9L DIESEL (Continued)

TORQUE
TORQUE CHART 5.9L DIESEL ENGINE
DESCRIPTION N´mIn.
Lbs.Ft.
Lbs.
Connecting RodÐBolts
Step 1 30 Ð 22
Step 2 60 Ð 44
Step 3 Rotate 60 degrees
Crankshaft Main CapÐBolts
Step 1 50 37
Step 2 80 59
Step 3 Rotate 90É
Cylinder HeadÐBolts
Step 1 70 Ð 52
Step 2 Back off 360 degrees
Step 3 105 Ð 77
Step 4 Verify 105 Ð 77
Step 5 Rotate All Bolts 1/4
Turn
Cylinder Head Cover Bolts 24 Ð 18
Breather Cover Bolts 24 Ð 18
HPC Nut 50 37
Fuel Delivery LinesÐBanjo 24 Ð 18
Fuel Drain LineÐBanjo 24 Ð 18
Fuel lineÐrail to cylinder
head30 Ð 22
Fuel lineÐpump to fuel rail 30 Ð 22
Injector fuel line brace 24 Ð 18
Fuel rail holddown bolt 24 18
Oil PanÐBolts 28 Ð 21
Oil PanÐDrain Plug 50 Ð 37
Oil Pressure RegulatorÐPlug 80 Ð 60
Oil Pressure Switch 18 Ð 13
Oil PumpÐBolts
Step1 8 Ð 6
Step2 24 Ð 18
Oil Suction Tube (Flange)Ð
Bolts24 Ð 18
Oil Suction Tube (Brace)Ð
Bolt43 Ð 32
Rocker Arm/PedestalÐBolts 36 Ð 27
SPECIAL TOOLS
5.9L DIESEL ENGINE
Universal Driver Handle - C4171
Crankshaft Barring Tool - 7471 - B
Crankshaft Front Oil Seal Installer - 8281
Valve Spring Compressor - 8319A
Test Plug - 8442
9 - 294 ENGINE 5.9L DIESELDR
ENGINE 5.9L DIESEL (Continued)

Filter Removal
(1) The housing cover is equipped with spring clips
(Fig. 6) and is hinged with plastic tabs. Unlatch clips
from top of air cleaner housing and tilt housing cover
up for cover removal.
(2) Remove air cleaner element from air cleaner
housing.
INSTALLATION
(1) Before installing new air cleaner element (fil-
ter), clean inside of air cleaner housing.
(2) Position air cleaner cover to tabs on front of air
cleaner housing. Latch spring clips to seal cover to
housing.
CYLINDER HEAD
DESCRIPTION
The cylinder head is constructed of cast iron and is
a one piece cross flow design with four valves per cyl-
inder. The arrangement of two intake and two
exhaust valves per cylinder allows for a centrally
located injector. The cylinder head also includes an
integral intake manifold, an integral thermostat
housing, and a longitudal fuel return rifle, which
exits at the rear of the head. The 24 valve design
also includes integrally cast valve guides and hard-
ened intake and exhaust valve seat inserts.
REMOVAL
(1) Disconnect battery negative cables.
(2) Raise vehicle on hoist.
(3) Drain engine coolant.
(4) Disconnect exhaust pipe from turbocharger
elbow.
(5) Lower vehicle.
(6) Disconnect air inlet temperature/pressure sen-
sor.
(7) Remove air cleaner housing and snorkel from
the vehicle. Cap off turbocharger air inlet to prevent
intrusion of dirt or foreign material.
(8) Disconnect cab heater core supply and return
hoses from the cylinder head and heater pipe.
(9) Disconnect turbocharger oil drain tube at rub-
ber hose connection. Cap off open ports to prevent
intrusion of dirt or foreign material.
(10) Disconnect turbocharger oil supply line at the
turbocharger end. Cap off open ports to prevent
intrusion of dirt or foreign material.
(11) Remove exhaust manifold-to-cylinder head
bolts, spacers, heat shield, retention straps, and cab
heater plumbing. Remove exhaust manifold and tur-
bocharger from the vehicle as an assembly.
(12) Remove cooling fan assembly.
(13) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(14) Remove cooling fan support from cylinder
block.
(15) Remove upper generator bolt, loosen lower
generator bolt, and rotate generator away from cylin-
der head.
(16) Disconnect radiator upper hose from the ther-
mostat housing.
(17) Disconnect the Intake Air Temperature, Man-
ifold Air Pressure, and Coolant Temperature sensor
connector.
(18) Remove the engine harness to cylinder head
attaching bolts and P-clips at front of head.
(19) Remove the throttle linkage cover (Fig. 8).
(20) Remove the six (6) accelerator pedal position
sensor assembly-to-cylinder head bracket bolts (Fig.
9) and secure the entire assembly out of the way.
Disconnect the APPS connector (Fig. 10).It is not
necessary to disconnect the cables from the
throttle control assembly.
(21) Remove the intake air grid heater wires from
the grid heater.
(22) Remove engine oil level indicator tube attach-
ing bolt at fuel filter housing bracket and inlet air
connection..
(23) Remove the charge air cooler-to-air inlet hous-
ing pipe.
Fig. 7 FILTER MINDERŸ - 5.9L DIESEL
1 - PRESS BUTTON TO RESET
2 - YELLOW DISC
3 - RED ZONE
4 - TO AIR FILTER HOUSING
5 - FILTER MINDER
9 - 298 ENGINE 5.9L DIESELDR
AIR CLEANER ELEMENT (Continued)

OIL
STANDARD PROCEDURE
STANDARD PROCEDURE - ENGINE OIL LEVEL
CAUTION: Do not overfill crankcase with engine oil,
oil foaming and oil pressure loss can result.
To ensure proper lubrication of an engine, the
engine oil must be maintained at an acceptable level.
The acceptable oil level is in the SAFE RANGE on
the engine oil dipstick (Fig. 113).
Unless the engine has exhibited loss of oil pres-
sure, run the engine for about five minutes before
checking oil level. Checking engine oil level of a cold
engine is not accurate.
(1) Position vehicle on level surface.
(2) With engine OFF, allow approximately ten min-
utes for oil to settle to bottom of crankcase, remove
engine oil dipstick.
(3) Wipe dipstick clean.
(4) Replace dipstick and verify it is seated in the
tube.
(5) Remove dipstick, with handle held above the
tip, take oil level reading.
(6) Add oil only if level is below the SAFE RANGE
area on the dipstick.
(7) Replace dipstick
STANDARD PROCEDURE - ENGINE OIL
SERVICE
WARNING: HOT OIL CAN CAUSE PERSONAL
INJURY.
NOTE: Change engine oil and filter at intervals
specified in the owner's manual.
(1) Operate the engine until the water tempera-
ture reaches 60ÉC (140ÉF). Shut the engine off.
(2) Use a container that can hold at least 14 liters
(15 quarts) to hold the used oil. Remove the oil drain
plug and drain the used engine oil into the container.
(3) Always check the condition of the used oil. This
can give you an indication of engine problems that
might exist.
²Thin, black oil indicates fuel dilution.
²Milky discoloration indicates coolant dilution.
(4) Clean the area around the oil filter head.
Remove the filter (Refer to 9 - ENGINE/LUBRICA-
TION/OIL FILTER - REMOVAL).
(5) Install new oil filter (Refer to 9 - ENGINE/LU-
BRICATION/OIL FILTER - INSTALLATION).
(6) Clean the drain plug and the sealing surface of
the pan. Check the condition of the threads and seal-
ing surface on the oil pan and drain plug.
(7) Install the drain plug. Tighten the plug to 50
N´m (37 ft. lbs.) torque.
(8) Use only High-Quality Multi-Viscosity lubricat-
ing oil in the Cummins Turbo Diesel engine. Choose
the correct oil for the operating conditions (Refer to
LUBRICATION & MAINTENANCE/FLUID TYPES -
DESCRIPTION).
(9) Fill the engine with the correct grade of new oil
(Refer to LUBRICATION & MAINTENANCE/FLUID
CAPACITIES - SPECIFICATIONS).
(10) Start the engine and operate it at idle for sev-
eral minutes. Check for leaks at the filter and drain
plug.
(11) Stop engine. Wait several minutes to allow the
oil to drain back to the pan and check the level
again.
USED ENGINE OIL DISPOSAL
Care should be exercised when disposing of used
engine oil after it has been drained from a vehicle's
engine.
1 - ROCKER ARM
2 - ROCKER SHAFT
3 - PEDESTAL
4 - FROM MAIN OIL RIFLE
5 - TO VALVE TRAIN
6 - MAIN OIL RIFLE
7 - FROM MAIN OIL RIFLE8 - TO CAMSHAFT
9 - TO PISTON COOLING NOZZLE
10 - FROM OIL COOLER
11 - CRANKSHAFT MAIN JOURNAL
12 - ROD JOURNAL
13 - TO ROD BEARING
14 - MAIN OIL RIFLE
Fig. 113 Oil Level Indicator (Dipstick)
1 - ADD OIL MARK
2 - O-RING
3 - SAFE RANGE
DRENGINE 5.9L DIESEL 9 - 341
OIL (Continued)

²Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
þ Engine overheating
þ Loss of coolant
þ Excessive steam (white smoke) emitting from
exhaust
þ Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test in this
section. An engine cylinder head gasket leaking
between adjacent cylinders will result in approxi-
mately a 50±70% reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING WITH COOLANT PRES-
SURE CAP REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure
cap. Start the engine and allow it to warm up until
thermostat opens.
If a large combustion/compression pressure leak
exists, bubbles will be visible in the coolant.COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE PRESSURE BUILT UP, BY CONTINUOUS
ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to
pressure cap neck. Start the engine and observe the
tester's pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also
be checked by using Bloc-Chek Kit C-3685-A or
equivalent. Perform test following the procedures
supplied with the tool kit.
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(3) Remove the heat shields (Fig. 7).
(4) Remove the intake manifold-to-generator
bracket support rod. Remove the generator (Refer to
8 - ELECTRICAL/CHARGING/GENERATOR -
REMOVAL).
(5) Remove closed crankcase ventilation system.
(6) Disconnect the evaporation control system.
(7) Remove the air cleaner.
(8) Perform the Fuel System Pressure release pro-
cedure (Refer to 14 - FUEL SYSTEM/FUEL DELIV-
ERY - STANDARD PROCEDURE). Disconnect the
Fig. 6 Cylinder Head Assembly
1 - SPARK PLUG
2 - INTAKE VALVES
3 - SPARK PLUG
4 - INTAKE VALVES
5 - SPARK PLUG
6 - SPARK PLUG
7 - INTAKE VALVE
8 - SPARK PLUG
9 - EXHAUST VALVE
10 - EXHAUST VALVES
11 - EXHAUST VALVES
Fig. 7 Spark Plug Wire Heat Shields (Left Side
Shown)
1 - EXHAUST MANIFOLD
2 - HEAT SHIELD
DRENGINE 8.0L 9 - 371
CYLINDER HEAD (Continued)

SPECIFICATIONS - TORQUE
DESCRIPTION N´m Ft. In.
Lbs. Lbs.
Adjusting StrapÐBolt 23 Ð 200
Air Heater Power SupplyÐ
Nuts14 Ð 124
Air Inlet HousingÐBolts 24 18 Ð
Cab Heater Supply/Return
LineÐNuts24 18 Ð
Exhaust ClampÐNuts 48 35 Ð
Exhaust Manifold to Cylinder
HeadÐBolts
(Diesel Engine) 43 32 Ð
Exhaust Manifold to Cylinder
HeadÐBolts
(5.9L) 31 23 Ð
Exhaust Manifold to Cylinder
HeadÐBolts
(8.0L) 22 Ð 195
Exhaust Pipe to ManifoldÐ
Bolts31 23 Ð
Generator MountingÐBolts 41 30 Ð
Charge Air Cooler
MountingÐBolts2Ð17
Charge Air Cooler DuctÐ
Nuts11 Ð 9 5
Heat ShieldÐNuts and Bolts 11 Ð 95
Turbocharger flange studs 24 18 Ð
Turbocharger MountingÐ
Nuts43 32 Ð
Turbocharger Oil Drain
TubeÐBolts24 18 Ð
Turbocharger Oil Supply
LineÐFitting24 18 Ð
Turbocharger V-Band
ClampÐNut9Ð75
Turbocharger Oil Supply
fitting (at Turbocharger)36 27 Ð
Turbocharger Oil Supply
fitting (at lube filter head)24 18 Ð
Turbocharger Drain Hose
Clamps8Ð71
SPECIAL TOOLS
CATALYTIC CONVERTER
DESCRIPTION - CATALYTIC CONVERTER
WARNING: THE NORMAL OPERATING TEMPERA-
TURE OF THE EXHAUST SYSTEM IS VERY HIGH.
THEREFORE, NEVER WORK AROUND OR ATTEMPT
TO SERVICE ANY PART OF THE EXHAUST SYSTEM
UNTIL IT IS COOLED. SPECIAL CARE SHOULD BE
TAKEN WHEN WORKING NEAR THE CATALYTIC
CONVERTER. THE TEMPERATURE OF THE CON-
VERTER RISES TO A HIGH LEVEL AFTER A SHORT
PERIOD OF ENGINE OPERATION TIME.
CAUTION: DO NOT remove spark plug wires from
plugs or by any other means short out cylinders.
Failure of the catalytic converter can occur due to a
temperature increase caused by unburned fuel
passing through the converter.
The stainless steel catalytic converter body is
designed to last the life of the vehicle. Excessive heat
can result in bulging or other distortion, but exces-
sive heat will not be the fault of the converter. If
unburned fuel enters the converter, overheating may
occur. If a converter is heat-damaged, correct the
cause of the damage at the same time the converter
is replaced. Also, inspect all other components of the
exhaust system for heat damage.
Unleaded gasoline must be used to avoid con-
taminating the catalyst core.
50 State emission vehicles incorporate two mini
catalytic converters located after the exhaust mani-
folds and before the inline catalytic converter.
OPERATION
The catalytic converter captures and burns any
unburned fuel mixture exiting the combustion cham-
bers during the exhaust stroke of the engine. This
process aids in reducing emissions output.
TURBOCHARGER TESTER 9022
11 - 4 EXHAUST SYSTEMDR
EXHAUST SYSTEM (Continued)

FUEL SYSTEM
TABLE OF CONTENTS
page page
FUEL DELIVERY - GAS....................1
FUEL INJECTION - GAS...................24FUEL DELIVERY - DIESEL.................56
FUEL INJECTION - DIESEL................79
FUEL DELIVERY - GAS
TABLE OF CONTENTS
page page
FUEL DELIVERY - GAS
DESCRIPTION..........................1
OPERATION............................2
STANDARD PROCEDURE - FUEL SYSTEM
PRESSURE RELEASE...................2
SPECIFICATIONS
FUEL SYSTEM PRESSURE..............3
TORQUE - FUEL SYSTEM...............3
SPECIAL TOOLS
FUEL SYSTEM........................5
FUEL FILTER/PRESSURE REGULATOR
DESCRIPTION..........................6
OPERATION............................6
FUEL LEVEL SENDING UNIT / SENSOR
DESCRIPTION..........................7
OPERATION............................7
REMOVAL.............................7
INSTALLATION..........................8
FUEL LINES
DESCRIPTION..........................8
QUICK CONNECT FITTING
DESCRIPTION..........................8
STANDARD PROCEDURE - QUICK-CONNECT
FITTINGS............................8FUEL PUMP
DESCRIPTION.........................12
OPERATION...........................12
FUEL PUMP MODULE
DESCRIPTION.........................12
OPERATION...........................12
REMOVAL.............................12
INSTALLATION.........................13
FUEL RAIL
DESCRIPTION.........................13
OPERATION...........................13
REMOVAL.............................13
INSTALLATION.........................18
FUEL TANK
DESCRIPTION.........................20
OPERATION...........................20
REMOVAL- EXCEPT DIESEL..............20
INSTALLATION - EXCEPT DIESEL..........22
INLET FILTER
REMOVAL.............................23
INSTALLATION.........................23
FUEL DELIVERY - GAS
DESCRIPTION
The fuel delivery system consists of:
²a fuel pump module containing the electric fuel
pump, fuel filter/fuel pressure regulator, fuel gauge
sending unit (fuel level sensor) and a secondary fuel
filter located at the bottom of the pump module
²fuel tubes/lines/hoses
²a combination fuel filter/fuel pressure regulator²quick-connect fittings
²fuel injector rail
²fuel tank
²fuel tank filler/vent tube assembly
²fuel tank filler tube cap
²accelerator pedal
²throttle cable
Certain fuel delivery components can be found in
(Fig. 1).
DRFUEL SYSTEM 14 - 1

OPERATION
Fuel is returned through the fuel pump module
and back into the fuel tank through the fuel filter/
fuel pressure regulator. A separate fuel return line
from the engine to the tank is not used.
The fuel tank assembly consists of: the fuel tank,
fuel pump module assembly, fuel pump module lock-
nut/gasket, and fuel tank check valve (refer to Fuel
Tank Check Valve for information).
A fuel filler/vent tube assembly using a pressure/
vacuum, 1/4 turn fuel filler cap is used. The fuel
filler tube contains a flap door located below the fuel
fill cap.
Also to be considered part of the fuel system is the
evaporation control system. This is designed to
reduce the emission of fuel vapors into the atmo-sphere. The description and function of the Evapora-
tive Control System is found in Emission Control
Systems.
Both fuel filters (at bottom of fuel pump module
and within fuel pressure regulator) are designed for
extended service. They do not require normal sched-
uled maintenance. Filters should only be replaced if
a diagnostic procedure indicates to do so.
STANDARD PROCEDURE - FUEL SYSTEM
PRESSURE RELEASE
Use following procedure if the fuel injector
rail is, or is not equipped with a fuel pressure
test port.
(1) Remove fuel fill cap.
Fig. 1 FUEL DELIVERY COMPONENTS
1 - FUEL TANK 8 - LDP FRESH AIR FILTER
2 - CHECK VALVE 9 - LEAK DETECTION PUMP
3 - LIQUID EXPANSION CHAMBER 10 - EVAP CANISTERS (2)
4 - FUEL FILTER / FUEL PRESSURE REGULATOR 11 - FUEL TANK STRAPS (2)
5 - QUICK-CONNECT FITTING AND FUEL LINE (TO ENGINE) 12 - CHECK VALVE
6 - EVAP LINE CONNECTION 13 - FUEL PUMP MODULE LOCK RING
7 - LEAK DETECTION PUMP FRESH AIR LINE 14 - FUEL PUMP MODULE
14 - 2 FUEL DELIVERY - GASDR
FUEL DELIVERY - GAS (Continued)

pump.Refer to Fuel Pump - Description and
Operation for more information.
If fuel pressure at the pressure regulator exceeds
approximately 49.2 psi, an internal diaphragm opens
and excess fuel pressure is routed back into the tank
through the bottom of pressure regulator.
Both fuel filters (at bottom of fuel pump module
and within fuel pressure regulator) are designed for
extended service. They do not require normal sched-
uled maintenance. Filters should only be replaced if
a diagnostic procedure indicates to do so.
FUEL LEVEL SENDING UNIT /
SENSOR
DESCRIPTION
The fuel gauge sending unit (fuel level sensor) is
attached to the side of the fuel pump module. The
sending unit consists of a float, an arm, and a vari-
able resistor track (card).
OPERATION
The fuel pump module has 4 different circuits
(wires). Two of these circuits are used for the fuel
gauge sending unit for fuel gauge operation, and for
certain OBD II emission requirements. The other 2
wires are used for electric fuel pump operation.
For Fuel Gauge Operation:A constant current
source is supplied to the resistor track on the fuel
gauge sending unit. This is fed directly from the
Powertrain Control Module (PCM).NOTE: For
diagnostic purposes, this 12V power source can
only be verified with the circuit opened (fuel
pump module electrical connector unplugged).
With the connectors plugged, output voltages
will vary from about 0.6 volts at FULL, to about
8.6 volts at EMPTY (about 8.6 volts at EMPTY
for Jeep models, and about 7.0 volts at EMPTY
for Dodge Truck models).The resistor track is
used to vary the voltage (resistance) depending on
fuel tank float level. As fuel level increases, the float
and arm move up, which decreases voltage. As fuel
level decreases, the float and arm move down, which
increases voltage. The varied voltage signal is
returned back to the PCM through the sensor return
circuit.
Both of the electrical circuits between the fuel
gauge sending unit and the PCM are hard-wired (not
multi-plexed). After the voltage signal is sent from
the resistor track, and back to the PCM, the PCM
will interpret the resistance (voltage) data and send
a message across the multi-plex bus circuits to the
instrument panel cluster. Here it is translated into
the appropriate fuel gauge level reading. Refer to
Instrument Panel for additional information.For OBD II Emission Monitor Requirements:
The PCM will monitor the voltage output sent from
the resistor track on the sending unit to indicate fuel
level. The purpose of this feature is to prevent the
OBD II system from recording/setting false misfire
and fuel system monitor diagnostic trouble codes.
The feature is activated if the fuel level in the tank
is less than approximately 15 percent of its rated
capacity. If equipped with a Leak Detection Pump
(EVAP system monitor), this feature will also be acti-
vated if the fuel level in the tank is more than
approximately 85 percent of its rated capacity.
REMOVAL
The fuel level sending unit (fuel level sensor) and
float assembly is located on the side of the fuel pump
module (Fig. 3).
(1) Remove fuel pump module from fuel tank.
Refer to Fuel Pump Module Removal/Installation.
(2) To remove sending unit from pump module, lift
on plastic locking tab (Fig. 4) while sliding sending
unit tracks.
(3) Disconnect 4±wire electrical connector (Fig. 3)
from fuel pump module. Separate necessary sending
unit wiring from connector using terminal pick /
removal tool. Refer to Special Tools in 8W Wiring for
tool part numbers.
Fig. 3 LOCATION - FUEL GAUGE SENDING UNIT
1 - FUEL FILTER / FUEL PRESSURE REGULATOR
2 - FUEL PUMP MODULE ASSEMBLY
3 - 4-WAY ELEC. CONNECT.
4 - FLOAT ARM
5 - ELEC. FUEL PUMP
6 - INLET FILTER
7 - FUEL GAUGE SENDING UNIT
8 - GASKET (SEAL)
DRFUEL DELIVERY - GAS 14 - 7
FUEL FILTER/PRESSURE REGULATOR (Continued)

INSTALLATION
CAUTION: Whenever the fuel pump module is ser-
viced, the rubber gasket must be replaced.
(1) Using a new gasket, position fuel pump module
into opening in fuel tank.
(2) Position locknut over top of fuel pump module.
Install locknut finger tight.
(3) Rotate module until embossed alignment arrow
(Fig. 15) points to center alignment mark. This step
must be performed to prevent float from contacting
side of fuel tank. Also be sure fitting on fuel filter/
fuel pressure regulator is pointed to drivers side of
vehicle.
(4) Install Special Tool 6856 (Fig. 16) to locknut.
(5) Tighten locknut. Refer to Torque Specifications.
(6) Install fuel tank. Refer to Fuel Tank Removal/
Installation.
FUEL RAIL
DESCRIPTION
The fuel injector rail is used to mount the fuel
injectors to the engine.
OPERATION
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 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.
CAUTION: The left and right sections of the fuel rail
are connected with either a flexible connecting
hose, or joints. Do not attempt to separate the rail
halves at these connecting hose or joints. Due to
the design of the connecting hose or joint, it does
not use any clamps. Never attempt to install a
clamping device of any kind to the hose or joint.
When removing the fuel rail assembly for any rea-
son, be careful not to bend or kink the connecting
hose or joint.
REMOVAL
3.7L V-6
WARNING: THE FUEL SYSTEM IS UNDER CON-
STANT PRESSURE EVEN WITH ENGINE OFF.
BEFORE SERVICING FUEL RAIL, FUEL SYSTEM
PRESSURE MUST BE RELEASED.CAUTION: The left and right fuel rails are replaced
as an assembly. Do not attempt to separate rail
halves at connector tubes (Fig. 18). Due to design
of tubes, it does not use any clamps. Never attempt
to install a clamping device of any kind to tubes.
When removing fuel rail assembly for any reason,
be careful not to bend or kink tubes.
(1) Remove fuel tank filler tube cap.
(2) Perform Fuel System Pressure Release Proce-
dure.
(3) Remove negative battery cable at battery.
(4) Remove air duct at throttle body air box.
(5) Remove air box at throttle body.
(6) Remove air resonator mounting bracket at
front of throttle body (2 bolts).
(7) Disconnect fuel line latch clip and fuel line at
fuel rail. A special tool will be necessary for fuel line
disconnection. Refer to Quick-Connect Fittings.
(8) Remove necessary vacuum lines at throttle
body.
(9) Disconnect electrical connectors at all 6 fuel
injectors. To remove connector refer to (Fig. 17). 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.
(10) Disconnect electrical connectors at all throttle
body sensors.
(11) Remove 6 ignition coils. Refer to Ignition Coil
Removal/Installation.
(12) Remove 4 fuel rail mounting bolts (Fig. 18).
(13) Gently rock and pullleftside of fuel rail until
fuel injectors just start to clear machined holes in
cylinder head. Gently rock and pullrightside of rail
until injectors just start to clear cylinder head holes.
Repeat this procedure (left/right) until all injectors
have cleared cylinder head holes.
(14) Remove fuel rail (with injectors attached)
from engine.
(15) If fuel injectors are to be removed, refer to
Fuel Injector Removal/Installation.
4.7L V-8
WARNING: THE FUEL SYSTEM IS UNDER CON-
STANT PRESSURE EVEN WITH ENGINE OFF.
BEFORE SERVICING FUEL RAIL, FUEL SYSTEM
PRESSURE MUST BE RELEASED.
DRFUEL DELIVERY - GAS 14 - 13
FUEL PUMP MODULE (Continued)