2002 DODGE RAM engine

FUEL INJECTION PUMP DATA
PLATE
SPECIFICATIONS
FUEL INJECTION PUMP DATA PLATE
Pertinent information about the fuel injection
pump is machined into a boss on the drivers side of
the fuel injection pump (Fig. 44).
FUEL LEVEL SENDING UNIT /
SENSOR
DESCRIPTION
The fuel gauge sending unit (fuel level sensor) is
attached to the side of the fuel tank module. The
sending unit consists of a float, an arm, and a vari-
able resistor track (card).
OPERATION
The fuel tank module on diesel powered models
has 3 different circuits (wires). Two of these circuits
are used at the fuel gauge sending unit for fuel
gauge operation. The other wire is used for a ground.
The diesel engine does not have a fuel tank module
mounted electric fuel pump. The electric fuel pump
(fuel transfer pump) is mounted to the engine.
For Fuel Gauge Operation:A constant input
voltage source of about 12 volts (battery voltage) is
supplied to the resistor track on the fuel gauge send-
ing unit. This is fed directly from the Powertrain
Control Module (PCM).NOTE: For diagnostic pur-
poses, this 12V power source can only be veri-
fied with the circuit opened (fuel tank module
electrical connector unplugged). With the con-
nectors plugged, output voltages will vary from
about .6 volts at FULL, to about 7.0 volts at
EMPTY.The resistor track is used to vary the volt-
age (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.
FUEL LINES
DESCRIPTION
DESCRIPTION
All fuel lines up to the fuel injection pump are con-
sidered low-pressure. This includes the fuel lines
from: the fuel tank to the fuel transfer pump, and
the fuel transfer pump to the fuel injection pump.
The fuel return lines, the fuel drain manifold and the
fuel drain manifold lines are also considered low-
pressure lines. High-pressure lines are used between
the fuel injection pump and the fuel injectors. Also
refer to High-Pressure Fuel Lines Description/Opera-
tion.
Fig. 44 Fuel Injection Pump Data Plate Location
1 - PUMP DATA PLATE
BR/BEFUEL DELIVERY - DIESEL 14 - 77

DESCRIPTIONÐHIGH PRESSURE FUEL LINES
The high-pressure fuel lines are the 6 lines located
between the fuel injection pump and the fuel injector
connector tubes (Fig. 45). All other fuel lines are con-
sidered low-pressure lines.
OPERATIONÐHIGH 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. If lines are ever
kinked or bent, they must be replaced. Use only the
recommended lines when replacement of high-pres-
sure fuel line is necessary.
High-pressure fuel lines deliver fuel under pres-
sure of up to approximately 120,000 kPa (17,405 PSI)
from the injection pump to the fuel injectors. The
lines 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 opera-
tion.
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.
DIAGNOSIS AND TESTING - HIGH-PRESSURE
FUEL LINE LEAKS
High-pressure fuel line leaks can cause starting
problems and poor engine performance.
WARNING: DUE TO EXTREME FUEL PRESSURES
OF UP TO 120,000 kPa (17,400 PSI), USE EXTREME
CAUTION WHEN INSPECTING FOR HIGH-PRES-
SURE FUEL LEAKS. DO NOT GET YOUR HAND
NEAR A SUSPECTED LEAK. INSPECT FOR HIGH-
PRESSURE FUEL LEAKS WITH A SHEET OF CARD-
BOARD. HIGH FUEL INJECTION PRESSURE CAN
CAUSE PERSONAL INJURY IF CONTACT IS MADE
WITH THE SKIN.
Start the engine. Move the cardboard over the
high-pressure fuel lines and check for fuel spray onto
the cardboard (Fig. 46). If a high-pressure line con-
nection is leaking, bleed the system and tighten the
connection. Refer to the Air Bleed Procedure in this
group for procedures. Replace damaged, restricted or
leaking high-pressure fuel lines with the correct
replacement line.
Fig. 45 High-Pressure Fuel Lines
Fig. 46 Typical Test for Leaks with Cardboard
1 - HIGH-PRESSURE LINE
2 - CARDBOARD
3 - FITTING
14 - 78 FUEL DELIVERY - DIESELBR/BE
FUEL LINES (Continued)

CAUTION: The high-pressure fuel lines must be
clamped securely in place in the 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.
REMOVAL
High-pressure lines are used between the fuel
injection pump and the fuel injectors only. 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.
CAUTION: Refer to Cleaning Fuel System Parts.
(1) Disconnect both negative battery cables from
both batteries. Cover and isolate ends of cables.
(2) Thoroughly clean fuel lines at cylinder head
and injection pump ends.
(3) Remove cable cover (Fig. 47). Cable cover is
attached with 2 Phillips screws, 2 plastic retention
clips and 2 push tabs (Fig. 47). Remove 2 Phillips
screws and carefully pry out 2 retention clips. After
clip removal, push rearward on front tab, and
upward on lower tab for cover removal.Do not
remove any cables at lever.(4) Disconnect wiring harness (clip) at bottom of
Accelerator Pedal Position Sensor (APPS) mounting
bracket (Fig. 48).
(5) Using 2 small screwdrivers, pry front wiring
clip (Fig. 49) from cable bracket housing. Position
wiring harness towards front of engine.
(6) Remove electrical connector from APPS by
pushing connector tab rearward while pulling down
on connector (Fig. 50).
(7) Disconnect 2 electrical cables from cable
mounting studs (Fig. 51) at intake air heater on top
of intake manifold.
(8) Remove engine oil dipstick from engine.
(9) Remove engine oil dipstick tube support
mounting bolt (Fig. 51) and position tube to side.
(10) Disconnect clamps and remove air tube
(intake manifold-to-intercooler) (Fig. 49).
(11) Remove 4 air intake housing mounting bolts
and remove housing (Fig. 52) and (Fig. 51). Position
ground cable at top of air intake housing to front of
engine.
(12) Remove intake manifold air heater element
block from engine (Fig. 53). Discard old upper and
lower gaskets
(13) Remove 3 cable bracket housing mounting
bolts (Fig. 52). Carefully position cable bracket and
cable assembly to side of engine.Leave cables con-
nected to lever.
Fig. 47 Cable/Lever/Throttle Linkage Cover
1 - CABLE/LEVER/LINKAGE COVER
2 - PUSH UP LOWER TAB
3 - SCREWS/CLIPS (2)
4 - TAB PUSH HERE
Fig. 48 Wiring Clip at APPS
1 - LEVER
2 - MOUNTING BOLTS (6)
3 - WIRE HARNESS CLIP
4 - CALIBRATION SCREWS (NO ADJUSTMENT)
5 - APPS ASSEMBLY
BR/BEFUEL DELIVERY - DIESEL 14 - 79
FUEL LINES (Continued)

Fig. 49 Air Tube (Typical)
1 - ENGINE OIL DIPSTICK TUBE
2 - TUBE BOLT
3 - CLAMPS
4 - AIR TUBE (INTAKE MANIFOLD TO CHARGE AIR COOLER
5 - CABLE BRACKET HOUSING
6 - FRONT WIRING CLIP
7 - GROUND CABLE
8 - RUBBER HOSE
9 - AIR INTAKE HOUSING
Fig. 50 Rear View of APPS
1 - APPS
2-TAB
3 - PUSH FOR REMOVAL
4 - APPS CONNECTOR
Fig. 51 Air Intake Housing (Rear View)
1 - TUBE MOUNTING BOLT
2 - HOUSING BOLTS (2)
3 - INTAKE HEATER CABLE MOUNTING STUDS (2)
4 - DIPSTICK TUBE
Fig. 52 Air Intake Housing (Front View)
1 - GROUND CABLE BOLT
2 - INTAKE AIR HOUSING
3 - CABLE BRACKET HOUSING BOLTS (3)
4 - GROUND CABLE
14 - 80 FUEL DELIVERY - DIESELBR/BE
FUEL LINES (Continued)

(14) Remove engine lifting bracket at rear of
intake manifold (2 bolts) (Fig. 54).
(15) Remove bolts from all fuel injection line sup-
port brackets at intake manifold.
(16) Place shop towels around fuel lines at fuel
injectors. Do not allow fuel to drip down side of
engine.CAUTION: WHEN LOOSENING OR TIGHTENING
HIGH-PRESSURE FITTINGS AT INJECTION PUMP,
USE A BACK-UP WRENCH ON DELIVERY VALVE AT
PUMP. DO NOT ALLOW DELIVERY VALVE TO
ROTATE.
(17) Loosen high-pressure line fittings at injection
pump (Fig. 55) beginning with cylinders 1, 2 and 4.
(18) Loosen high-pressure lines at cylinder head
for cylinders 1, 2 and 4 (Fig. 54).
(19) Carefully remove front line bundle from
engine.Do not bend lines while removing.While
removing front line bundle, note line position.
(20) Loosen high-pressure lines at injection pump
beginning with cylinders 3, 5 and 6.
(21) Loosen high-pressure lines at cylinder head
for cylinders 3, 5 and 6 (Fig. 54).
(22) Carefully remove rear line bundle from
engine.Do not bend lines while removing.While
removing rear line bundle, note line position.
INSTALLATION
High-pressure lines are used between the fuel
injection pump and the fuel injectors only. 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.
Fig. 53 Intake Manifold Air Heater (Elements)
1 - AIR HEATER ELEMENTS
2 - LOWER GASKET
3 - BLOCK
4 - UPPER GASKET
Fig. 54 High-Pressure Fuel Lines
Fig. 55 High Pressure Lines at Fuel Injection Pump
1 - FPCM ELECTRICAL CONNECTOR
2 - HIGH-PRESSURE FUEL LINES
3 - FITTINGS
4 - FUEL INJECTION PUMP
5 - FPCM
BR/BEFUEL DELIVERY - DIESEL 14 - 81
FUEL LINES (Continued)

CAUTION: Be sure that the high-pressure fuel lines
are installed in the same order that they were
removed.
(1) Lubricate threads of injector line fittings with
clean engine oil.
(2) Loosen, but do not remove, all fuel line support
bracket bolts.
(3) Installrearinjection line bundle beginning
with cylinder head (fuel injector) connections, fol-
lowed by injection pump connections. Tighten all fit-
tings finger tight.
(4) Tighten fittings at fuel injector ends for cylin-
ders number 6 and 5 to 38 N´m (28 ft. lbs.) torque.
Do not tighten number 3 line at this time. It
will be tightened during bleeding procedure.
(5) Tighten 3 fittings at fuel injection pump ends
to 24 N´m (18 ft. lbs.) torque.
(6) Installfrontinjection line bundle beginning
with cylinder head (fuel injector) connections, fol-
lowed by injection pump connections. Tighten all fit-
tings finger tight.
(7) Tighten fitting at fuel injector end for cylinder
number 2 to 38 N´m (28 ft. lbs.) torque.Do not
tighten lines number 1 or 4 at this time. They
will be tightened during bleeding procedure.
(8) Tighten remaining 3 fittings at fuel injection
pump ends to 24 N´m (18 ft. lbs.) torque.
(9) Install fuel line support bracket bolts to intake
manifold and tighten to 24 N´m (18 ft. lbs.) torque.
CAUTION: Be sure fuel lines are not contacting
each other or any other component. Noise will
result.
(10) Install engine lifting bracket at rear of intake
manifold. Tighten 2 bolts to 77 N´m (57 ft. lbs.)
torque.
(11) Install cable bracket housing/cable assembly
and tighten 3 mounting bolts to 24 N´m (18 ft. lbs.)
torque.
(12) Clean any old gasket material below and
above intake manifold air heater element block. Also
clean mating areas at intake manifold and air intake
housing.
(13) Using new gaskets, position intake manifold
air heater element block to engine.
(14) Install air intake housing and position ground
cable. Install 4 mounting bolts and tighten to 24 N´m
(18 ft. lbs.) torque.
(15) Install air tube (intake manifold-to-charge air
cooler) (Fig. 49). Tighten clamps to 8 N´m (72 in. lbs.)
torque.
(16) Install engine oil dipstick tube support mount-
ing bolt and tighten to 24 N´m (18 ft. lbs.) torque.
(17) Install engine oil dipstick to engine.(18) Connect 2 electrical cables to cable mounting
studs.
(19) Connect electrical connector to bottom of
APPS by pushing connector upward until it snaps
into position.
(20) Connect wiring harness (clip) at bottom of
Accelerator Pedal Position Sensor (APPS) mounting
bracket (Fig. 48).
(21) Connect front wiring clip (Fig. 49) to cable
bracket housing.
(22) Install cable cover (Fig. 47).
(23) Connect both negative battery cables to both
batteries.
(24) Bleed air from fuel system. Do this at fuel
injector ends of lines. Use cylinders numbers 1, 3 and
4 for bleeding. (Refer to 14 - FUEL SYSTEM/FUEL
DELIVERY - STANDARD PROCEDURE). After
bleeding, tighten fittings to 38 N´m (28 ft. lbs.)
torque.
(25) Check lines/fittings for leaks.
FUEL TANK
DESCRIPTION - DIESEL FUEL TANK
The fuel tank is similar to the tank used with gas-
oline powered models. The tank is equipped with a
separate fuel return line and a different fuel tank
module for diesel powered models. A fuel tank
mounted, electric fuel pump is not used with diesel
powered models. Refer to Fuel Tank Module for addi-
tional information.
For removal and installation procedures, refer to
Fuel Tank - Gasoline Engines.
FUEL TANK MODULE
DESCRIPTION
An electric fuel pump isnot usedin the fuel tank
module for diesel powered engines. Fuel is supplied
by the engine mounted fuel transfer pump and the
fuel injection pump.
The fuel tank module is installed in the top of the
fuel tank (Fig. 56). The fuel tank module (Fig. 56)
contains the following components:
²Fuel reservoir
²A separate in-tank fuel filter
²Rollover valve
²Fuel gauge sending unit (fuel level sensor)
²Fuel supply line connection
²Fuel return line connection
²Auxiliary non-pressurized fuel supply fitting
OPERATION
Refer to Fuel Gauge Sending Unit.
14 - 82 FUEL DELIVERY - DIESELBR/BE
FUEL LINES (Continued)

REMOVAL
(1) Drain and remove fuel tank. Refer to Fuel
Tank Removal/Installation.
(2) Thoroughly clean area around tank module at
top of tank.
(3) The plastic fuel tank module locknut is
threaded onto fuel tank. Install Special Tool 6856 to
locknut and remove locknut (Fig. 57). The fuel tank
module will spring up when locknut is removed.
(4) Remove module from fuel tank.
INSTALLATION
CAUTION: Whenever the fuel tank module is ser-
viced, the rubber gasket must be replaced.
(1) Thoroughly clean locknut and locknut threads
at top of tank.
(2) Using new gasket, carefully position fuel tank
module into opening in fuel tank.
(3) Position locknut over top of fuel tank module.
Install locknut finger tight.
(4) When looking down at tank from drivers side of
tank, the arrow at top of module should be aligned
between two marks stamped into tank (approximate-
ly 2 o'clock position). The fuel line connectors, roll
over valve and fuel gauge electrical connector should
all be pointed to drivers side of vehicle. Rotate and
align module/tank marks if necessary before tighten-
ing locknut.This step must be performed to pre-vent the module's float from contacting side of
fuel tank.
(5) Tighten locknut to 24±44 N´m (18±32 ft. lbs.)
torque.
(6) Install fuel tank. Refer to Fuel Tank Removal/
Installation.
FUEL TRANSFER PUMP
DESCRIPTION
The fuel transfer pump (fuel lift pump) is located
on the left-rear side of the engine cylinder block
above the starter motor (Fig. 58). The 12±volt electric
vane-type pump is operated and controlled by the
Engine Control Module (ECM) (Fig. 59).
OPERATION
The purpose of the fuel transfer pump is to supply
(transfer) a low-pressure fuel source:fromthe fuel
tank,throughthe fuel filter/water separator andto
the fuel injection pump. Here, the low-pressure is
raised to a high-pressure by the fuel injection pump
for operation of the high-pressure fuel injectors.
Check valves within the pump, control direction of
fuel flow and prevent fuel bleed-back during engine
shut down.
Normal current flow to the pump is 12 amperes.
With the engine running, the pump has2modes of
operation: Mode 1: 100 percent duty-cycle with a
minimum pressure of 10 psiexcept when the
engine is cranking.Mode 2: 15 percent duty-cycle
with maximum pressure of 7 psiwith the engine
cranking
The 15 percent duty-cycle is used to limit injection
pump inlet pressure until the engine is running.
Fig. 56 Top View of Fuel Tank ModuleÐDiesel
1 - AUXILIARY CAPPED FITTING
2 - FUEL PUMP MODULE
3 - FUEL SUPPLY/RETURN FITTINGS
4 - ELECTRICAL CONNECTOR
5 - LOCKNUT
6 - ROLLOVER VALVE
Fig. 57 Locknut Removal/InstallationÐTYPICAL
MODULE
1 - SPECIAL TOOL 6856
2 - LOCKNUT
BR/BEFUEL DELIVERY - DIESEL 14 - 83
FUEL TANK MODULE (Continued)

The transfer pump is self-priming: When the key is
first turned on (without cranking engine), the pump
will operate for approximately 1/4 second and then
shut off. The pump will also operate for up to 25 sec-
onds after the starter is engaged, and then disen-
gaged and the engine is not running. The pump
shuts off immediately if the key is on and the engine
stops running.
The fuel volume of the transfer pump will always
provide more fuel than the fuel injection pump
requires. Excess fuel is returned from the injection
pump through an overflow valve. The valve is located
on the side of the injection pump (Fig. 60). It is also
used to connect the fuel return line to the side of the
injection pump. This valve opens at approximately 97
kPa (14 psi) and returns fuel to the fuel tank
through the fuel return line.
DIAGNOSIS AND TESTING - FUEL TRANSFER
PUMP PRESSURE
The following tests will include: pressures
tests of fuel transfer pump (engine running and
engine cranking), a test for supply side restric-
tions, and a test for air in fuel supply side.
Fig. 58 Fuel Transfer Pump Location
1 - OIL PRESSURE SENSOR
2 - PUMP BRACKET NUTS (3)
3 - SUPPORT BRACKET BOLT
4 - BANJO BOLT (REAR)
5 - FUEL SUPPLY LINE
6 - ELECTRICAL CONNECTOR
7 - BANJO BOLT (FRONT)
8 - FUEL TRANSFER PUMP
Fig. 59 Engine Control Module (ECM) Location
1 - ENGINE CONTROL MODULE (ECM)
2 - HEX HEADED BOLT
3 - 50-WAY CONNECTOR
4 - FUEL TRANSFER PUMP
5 - MOUNTING BOLTS (3)
Fig. 60 Injection Pump Overflow Valve Location
1 - FUEL SUPPLY LINE
2 - FUEL RETURN LINE
3 - BANJO BOLT (TEST PORT FITTING)
4 - OVERFLOW VALVE
5 - BANJO FITTING
14 - 84 FUEL DELIVERY - DIESELBR/BE
FUEL TRANSFER PUMP (Continued)