1998 DODGE RAM 1500 fuel pump

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 fuel line connectors and fuel gauge electri-
cal connector should all be pointed to drivers side of
vehicle. Rotate and align 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 attached
to the rear of the fuel filter/water separator housing.
The 12±volt electric pump is operated and controlled
by the Engine Control Module (ECM).
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.
Maximum current flow to the pump is 5 amperes.
With the engine running, the pump has a 100 per-
cent duty-cycle.
The transfer pump is self-priming: When the key is
first turned on (without cranking engine), the pump
will operate for approximately 2 seconds 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, and then back to
the fuel tank.
REMOVAL
The fuel transfer pump (fuel lift pump) is attached
to the rear of the fuel filter/water separator housing
(Fig. 23).
Fig. 21 FUEL TANK MODULE - DIESEL
1 - TOP OF FUEL TANK
2 - AUX. FITTING
3 - ELEC. CONNECTOR
4 - FUEL TANK MODULE (TOP)
5 - LOCKNUT
6 - FUEL SUPPLY LINE
7 - FUEL RETURN LINE
Fig. 22 LOCKNUT REMOVAL/INSTALLATION -
TYPICAL MODULE
1 - SPECIAL TOOL 6856
2 - LOCKNUT
14 - 64 FUEL DELIVERY - DIESELDR
FUEL TANK MODULE (Continued)

(1) Drain fuel from fuel filter housing. Refer to
Fuel Filter/Water Separator - Removal. See Draining.
(2) Disconnect electrical connector (Fig. 23) from
fuel transfer pump.
(3) Disconnect fuel tank supply line from fuel
transfer pump extension line. This is done at discon-
nection point at inside of left inner frame rail (Fig.
24). Refer to quick-connect fittings for procedures.
(4) Remove 4 pump mounting bolts (hex-allen),
and remove pump from fuel filter housing.
(5) Confirm that transfer pump o-ring is also
removed from fuel filter housing.
INSTALLATION
(1) Install a new o-ring to fuel transfer pump.
(2) Lubricate o-ring and OD of transfer pump inlet
connector.
(3) Position fuel transfer pump onto fuel filter
housing.Do not use mounting bolts to draw
transfer pump to filter housing.
(4) Be sure pump is positioned flat to fuel filter
housing. Install mounting bolts and evenly tighten to
7 N´m (61 in. lbs.).
(5) Connect fuel line extension at fuel supply line.
(6) Connect electrical connector to pump.
(7)Prime System:Cycle key to actuate transfer
pump, or use DRB Scan Tool to actuate transfer
pump. Check for leaks.
(8) Operate engine and check for fuel leaks.
Fig. 23 FUEL TRANSFER (LIFT) PUMP
1 - FILTER HOUSING
2 - ELEC. CONNECTOR
3 - FUEL TRANSFER (LIFT) PUMP
4 - FUEL LINE EXTENTION
5 - MOUNTING BOLTS (4)
Fig. 24 TRANSFER PUMP FUEL LINE CONNECT
1 - LEFT INNER FRAME RAIL
2 - FUEL RETURN LINE
3 - FUEL SUPPLY LINE
4 - QUICK-CONNECT FITTING
DRFUEL DELIVERY - DIESEL 14 - 65
FUEL TRANSFER PUMP (Continued)

CASCADE OVERFLOW VALVE
DESCRIPTION
The cascade overflow valve is located on the top/
rear side of the fuel injection pump (Fig. 25).
OPERATION
When the fuel control actuator (FCA) is opened,
the maximum amount of fuel is being delivered to
the fuel injection pump. The cascade valve regulates
how much excess fuel is used for lubrication of the
injection pump, and is also used to route excess fuel
through the drain circuit and back into the fuel tank.
REMOVAL
REMOVAL/INSTALLATION
The cascade overflow valve is not serviced sepa-
rately.
WATER IN FUEL SENSOR
DESCRIPTION
The Water-In-Fuel (WIF) sensor is located on the
side of the fuel filter/water separator canister (Fig.
26).
OPERATION
The sensor sends an input to the Engine Control
Module (ECM) when it senses water in the fuel filter/
water separator. As the water level in the filter/sep-
arator increases, the resistance across the WIF
sensor decreases. This decrease in resistance is sent
as a signal to the ECM and compared to a high
water standard value. Once the value reaches 30 to
40 kilohms, the ECM will activate the water-in-fuel
warning lamp through CCD bus circuits. This all
takes place when the ignition key is initially put in
the ON position. The ECM continues to monitor the
input while the engine is running.
REMOVAL
The Water-In-Fuel (WIF) sensor is located at the
side of fuel filter/water separator canister. Refer to
Fuel Filter/Water Separator Removal/Installation for
WIF sensor removal/installation procedures.
Fig. 25 OVERFLOW VALVE
1 - BANJO BOLTS
2 - PUMP MOUNTING NUTS (3)
3 - FUEL INJECTION PUMP
4 - CASCADE OVERFLOW VALVE
Fig. 26 FILTER HOUSING
1 - FILTER HOUSING
2 - FUEL HEATER AND THERMOSTAT
3 - FUEL HEATER MOUNTING SCREWS
4 - FUEL HEATER ELEC. CONNECTOR
5 - WIF SENSOR
6 - WIF SENSOR ELEC. CONNECTOR
7 - DRAIN HOSE
8 - DRAIN VALVE MOUNTING SCREWS
9 - DRAIN VALVE
14 - 66 FUEL DELIVERY - DIESELDR

FUEL DRAIN CIRCUIT
OPERATION
The Fuel Drain Circuit incorporates several
sources of fuel return. Fuel travels from the fuel tank
to the fuel transfer pump and is forced through the
fuel filter. This fuel then travels into the fuel injec-
tion pump. It then goes to a fuel drain line and
returns back to the fuel tank.
The fuel that flows to the fuel pump is pressurized
by a gear pump and internally transferred to the fuel
injection pump. At this point the fuel is channeled
into two passages. One passage sends fuel to the
FCA (Fuel Control Actuator). The other passage
sends fuel to the cascade overflow valve. The over-
flow valve sends some fuel to a lubrication passage.
The rest of the fuel is sent to a drain passage which
connects to an external fuel line.Fuel that travels through the FCA is pressurized
by the fuel injection pump and sent through an
external high pressure fuel line to the fuel rail. At
the fuel rail, fuel is sent to the fuel injectors. If fuel
pressure in the fuel rail becomes excessive, the pres-
sure limiting valve opens and sends fuel through an
external fuel line.
At the fuel injector, fuel that is not injected is used
for lubrication of the fuel injectors. This fuel then
travels through an internal passage that is connected
to the rear of the cylinder head, an then into an
external fuel line. This line is connected to the vehi-
cles fuel return line, and returns excess fuel to the
fuel tank.
DRFUEL DELIVERY - DIESEL 14 - 67

INSTALLATION
Engine Mounted Sensor :
The APPS is serviced (replaced) as one assembly
including the lever, brackets and sensor. The APPS is
calibrated to its mounting bracket.
(1) Snap electrical connector into bottom of sensor.
(2) Position APPS assembly to engine and install 6
bolts. Tighten bolts to 24 N´m (18 ft. lbs.) torque.
(3) Connect wiring harness clip at bottom of
bracket.
(4) Refer to Group 21, Transmission for transmis-
sion control cable installation procedures.
(5) Install speed control cable into mounting
bracket. Be sure pinch tabs have secured cable.
(6) Install throttle cable into mounting bracket. Be
sure pinch tabs have secured cable.
(7) Connect throttle cable at lever (snaps on).
(8) Connect speed control cable to lever by pushing
cable connector rearward onto lever pin while hold-
ing lever forward.
(9) Install cable cover.
(10) Connect both negative battery cables to both
batteries.
(11) If necessary, use DRB IIItScan Tool to erase
any Diagnostic Trouble Codes (DTC's) from ECM.Battery Tray Mounted Sensor :
(1) Install Accelerator Pedal Position Sensor
(APPS) cable to accelerator pedal. Refer to Accelera-
tor Pedal Removal / Installation.
(2) Connect electrical connector to APPS.
(3) If necessary, connect cable to APPS lever ball
socket (snaps on).
(4) Snap APPS cable cover closed.
(5) Position APPS assembly to bottom of battery
tray and install 3 bolts. Refer to Torque Specifica-
tions.
(6) Install wheelhouse liner. Refer to Body.
(7) Perform the following procedure:
(a) Connect negative battery cables to both bat-
teries.
(b) Turn key switch ON, but do not crank
engine.
(c) Leave key switch ON for a minimum of 10
seconds. This will allow ECM to learn electrical
parameters.
(8) If necessary, use DRB IIItScan Tool to erase
any Diagnostic Trouble Codes (DTC's) from ECM.
CAMSHAFT POSITION
SENSOR
DESCRIPTION
The Camshaft Position Sensor (CMP) on the 5.9L
diesel engine is located below the fuel injection
pump. It is bolted to the back of the timing gear
housing.
OPERATION
The diesel Camshaft Position Sensor (CMP) con-
tains a hall effect device. A rotating target wheel
(tonewheel) for the CMP is located on the camshaft
gear. This hall effect device detects notches located
on the back side of the camshaft gear. As the cam-
shaft gear rotates, the notches pass the tip of the
CMP.
When the leading edge of the notch passes the tip
of the CMP, the following occurs: The interruption of
magnetic field causes the voltage to switch high
resulting in a signal of approximately 5 volts.
When the trailing edge of the notch passes the tip
of the CMP, the following occurs: The change of the
magnetic field causes the signal voltage to switch low
to 0 volts.
The CMP (Fig. 8) provides a signal to the Engine
Control Module (ECM) at all times when the engine
is running. The ECM uses the CMP information pri-
marily on engine start-up. Once the engine is run-
ning, the ECM uses the CMP as a backup sensor for
engine speed. The Crankshaft Position Sensor (CKP)
Fig. 7 APPS CABLE (OFF ENGINE MOUNTING)
1 - APPS LEVER
2 - BALL SOCKET
3 - SWING-DOWN DOOR
4 - CABLE CLIP
5 - CABLE
DRFUEL INJECTION - DIESEL 14 - 71
ACCELERATOR PEDAL POSITION SENSOR (Continued)

is the primary engine speed indicator for the engine
after the engine is running.
REMOVAL
The Camshaft Position Sensor (CMP) on the 5.9L
diesel engine is located below the fuel injection
pump. It is bolted to the back of the timing gear
housing (Fig. 9).
(1) Disconnect electrical connector at CMP sensor
(Fig. 9).
(2) Remove sensor mounting bolt.
(3) Carefully twist sensor from timing gear hous-
ing.
(4) Check condition of sensor o-ring.
INSTALLATION
(1) Clean out machined hole in back of timing gear
housing (cover).
(2) Apply a small amount of engine oil to sensor
o-ring.
(3) Install sensor into timing gear housing (cover)
with a slight rocking action. Do not twist sensor into
position as damage to o-ring may result.
CAUTION: Before tightening sensor mounting bolt,
be sure sensor is completely flush to back of timingchain housing (cover). If sensor is not flush, dam-
age to sensor mounting tang may result.
(4) Install mounting bolt and tighten. Refer to
Torque Specifications.
(5) Connect electrical connector to sensor.
CRANKSHAFT POSITION
SENSOR
DESCRIPTION
The Crankshaft Position Sensor (CKP) on the die-
sel engine is attached at the front / left side of the
engine next to the engine harmonic balancer (crank-
shaft damper).
OPERATION
The Crankshaft Position Sensor (CKP) is the pri-
mary engine speed indicator for the engine after the
engine is running (Fig. 10). The CKP contains a hall
effect device. A rotating, notched target wheel (tone-
wheel) for the CKP is located on the engine harmonic
balancer (Fig. 11). This hall effect device detects
notches located on the tonewheel. As the tonewheel
rotates, the notches pass the tip of the CKP.
Fig. 8 5.9L DIESEL CMP
1 - CMP
2 - FUEL INJECTION PUMP (BOTTOM)
3 - ELECTRONIC CONTROL MODULE (ECM)
4 - ECM ELEC. CONNECTOR
5 - CMP ELEC. CONNECTOR
6 - CMP MOUNTING BOLT
7 - BACK OF TIMING GEAR HOUSING
Fig. 9 5.9L DIESEL CMP
1 - CMP
2 - FUEL INJECTION PUMP (BOTTOM)
3 - ELECTRONIC CONTROL MODULE (ECM)
4 - ECM ELEC. CONNECTOR
5 - CMP ELEC. CONNECTOR
6 - CMP MOUNTING BOLT
7 - BACK OF TIMING GEAR HOUSING
14 - 72 FUEL INJECTION - DIESELDR
CAMSHAFT POSITION SENSOR (Continued)

FUEL CONTROL ACTUATOR
DESCRIPTION
The Fuel Control Actuator (FCA) is located at the
rear of the high-pressure, fuel injection pump (Fig.
13).
OPERATION
The Fuel Control Actuator (FCA) is an electroni-
cally controlled solenoid valve. The ECM controls the
amount of fuel that enters the high-pressure pump-
ing chambers by opening and closing the FCA based
on a demanded fuel pressure. When the FCA is
opened, the maximum amount of fuel is being sup-
plied to the fuel injection pump. Any fuel that does
not enter the injection pump is directed to the cas-
cade overflow valve. The cascade overflow valve reg-
ulates how much excess fuel is used for lubrication of
the pump and how much is returned to the fuel tank
through the drain manifold.
An audible click from the FCA is normal when
operating the key from the ON to the OFF position.
REMOVAL
The Fuel Control Actuator (FCA) is a non-servi-
cable part.
FUEL INJECTOR
DESCRIPTION
Six individual, solenoid actuated high-pressure fuel
injectors are used (Fig. 14). The injectors are verti-
cally mounted into a bored hole in the top of the cyl-
inder head. This bored hole is located between the
intake/exhaust valves. High-pressure connectors (Fig.
15), mounted into the side of the cylinder head, con-
nect each fuel injector to each high-pressure fuel line.
OPERATION
High-pressure fuel is supplied from the injection
pump, through a high-pressure fuel line, into a fuel
rail, through high-pressure lines, through steel con-
nectors and into the solenoid actuated fuel injector.
The ECM actuates the solenoid causing the needle
valve to rise and fuel flows through the spray holes
in the nozzle tip into the combustion chamber.
Each fuel injector is connected to the fuel rail by a
high-pressure fuel line and a steel connector. This
steel connector is positioned into the cylinder head
and sealed with an o-ring. The connector is retained
in the cylinder head by a nut (fitting) that is
threaded into the cylinder head.
Fig. 13 FUEL CONTROL ACTUATOR
1 - ACTUATOR MOUNTING BOLTS
2 - FCA (FUEL CONTROL ACTUATOR)
3 - ACTUATOR ELECTRICAL CONNECTOR
Fig. 14 FUEL INJECTOR - DIESEL
1 - SOLENOID ELECTRICAL CONNECTOR STUDS
2 - MOUNTING BOLTS
3 - MOUNTING PLATES
4- COPPER SEALING WASHER
5 - INJECTOR TIP
6 - INJECTOR O-RING
7 - INJECTOR ELECTRICAL SOLENOID
14 - 74 FUEL INJECTION - DIESELDR

(6) Install injector into cylinder head with male
connector port facing the intake manifold. Push down
on fuel injector mounting flange to engage o-ring and
seat injector.
(7) Tightening Sequence:
(a) Install fuel injector holdown clamp (mount-
ing flange) bolts.Do a preliminary tightening
of these bolts to 5 N´m (44 in. lbs.) torque.
This preliminary tightening insures the fuel
injector is seated and centered.
(b) After tightening, relieve bolt torque, but
leave both bolts threaded in place.
(c) Install high-pressure connector and retaining
nut. Do a preliminary tightening to 15 N´m (11 ft.
lbs.) torque.
(d) Alternately tighten injector holdown bolts to
10 N´m (89 in. lbs.) torque.
(e) Do a final tightening of the high-pressure
connector and retaining nut. Tighten to 50 N´m (37
ft. lbs.) torque.
(8) Connect injector solenoid wires and nuts to top
of injectors (Fig. 18). Tighten connector nuts to 1.25
N´m (11 in. lbs.) torque.Be very careful not to
overtighten these nuts as damage to fuel injec-
tor will occur.
(9) Install exhaust rocker arm assembly. Refer to
Engine.
(10) Set exhaust valve lash. Refer to Engine.
(11) Install high pressure fuel line. Refer to Torque
Specifications.Be sure to use a secondary
back-up wrench on the connector nut (fitting)
while torquing fuel line fitting.Refer to Fuel Line
Installation for additional information.
(12) Install valve cover. Refer to Engine.
(13) Install breather assembly.
(14) Connect negative battery cables to both bat-
teries.
FUEL INJECTOR RAIL
DESCRIPTION
The fuel injector rail is bolted to the top of the
intake manifold.
OPERATION
The fuel rail is used as a distribution device to
supply high-pressure fuel to the high-pressure fuel
lines.
REMOVAL
CAUTION: Cleanliness cannot be overemphasized
when handling or replacing diesel fuel system com-
ponents. This especially includes the fuel injectors,
high-pressure fuel lines and fuel injection pump.Very tight tolerances are used with these parts. Dirt
contamination could cause rapid part wear and pos-
sible plugging of fuel injector nozzle tip holes. This
in turn could lead to possible engine misfire.
Always wash/clean any fuel system component
thoroughly before disassembly and then air dry.
Cap or cover any open part after disassembly.
Before assembly, examine each part for dirt, grease
or other contaminants and clean if necessary. When
installing new parts, lubricate them with clean
engine oil or clean diesel fuel only.
(1) Disconnect both negative battery cables at both
batteries. Isolate ends of both cables.
(2) Disconnect electrical connector at fuel pressure
sensor.
(3) Remove banjo bolt at fuel limiting valve.
(4) Disconnect necessary wiring harness retention
clips from intake manifold.
(5) Lift 2 rubber covers to gain access to positive
(+), intake heater cable nuts. Remove 2 nuts and
remove 2 cables from studs.
(6) Carefully remove 4 high-pressure fuel lines
from top of injector rail engine. Note position of each
line while removing.Do not bend lines while
removing.
CAUTION: WHEN LOOSENING OR TIGHTENING
HIGH-PRESSURE LINES ATTACHED TO A SEPA-
RATE FITTING, USE A BACK-UP WRENCH ON FIT-
TING. DO NOT ALLOW FITTING TO ROTATE.
DAMAGE TO BOTH FUEL LINE AND FITTING WILL
RESULT.
(7) Carefully remove 2 high-pressure fuel lines at
each end of injector rail. Note position of each line
while removing.Do not bend lines while remov-
ing.
(8) Remove fuel line connecting injector pump to
fuel rail.
(9) Remove 3 injector rail mounting bolts (Fig. 22).
(10) Remove rail from top of intake manifold.
INSTALLATION
(1) Clean any dirt/debris from top of intake mani-
fold and bottom of fuel rail.
(2) Position fuel rail to top of manifold and install
3 mounting bolts. Refer to Torque Specifications.
(3) Install all high-pressure lines to rail. Refer to
Fuel Lines for procedures.
(4) Reposition wiring harness to intake manifold
and install new tie wraps.
(5) Install and tighten fuel limiting valve banjo
bolt. Refer to Torque Specifications.
(6) Connect electrical connector to fuel pressure
sensor.
(7) Position 2 positive (+) cables to intake heater
studs. Install 2 nuts.
14 - 78 FUEL INJECTION - DIESELDR
FUEL INJECTOR (Continued)