2002 DODGE RAM Fuel

(2) Thoroughly clean area around transfer pump
and fuel lines of any contamination.
(3) Remove starter motor. Refer to Starter Remov-
al/Installation in 8, Starting System for procedures.
(4) Place a drain pan below the pump.
(5) Disconnect fuel line quick-connect fitting at
fuel supply line (Fig. 64) at rear of pump.
(6) Remove support bracket bolt at top of pump
(Fig. 64).
(7) Remove front and rear banjo bolts at pump
(Fig. 64).
(8) Disconnect electrical connector at side of pump
(Fig. 64).
(9) Remove three pump bracket nuts (Fig. 64) and
remove pump from vehicle.
INSTALLATION
The fuel transfer pump (fuel lift pump) is located
on left side of engine, below and rearward of fuel fil-
ter (Fig. 64).
(1) Install new gaskets to fuel supply line/support
bracket and banjo bolt at rear of pump. Install line
and banjo bolt to pump.Do nottighten banjo bolt at
this time.
(2) Install new gaskets to fuel line and banjo bolt
at front of pump.
(3) Position 3 pump studs into pump mounting
bracket and install 3 nuts.Do nottighten nuts at
this time.
(4) Install support bracket bolt (Fig. 64).Do not
tighten bolt at this time.
(5) Tighten 3 pump nuts to 12 N´m (9 ft. lbs.)
torque.
(6) Tighten both banjo bolts to 24 N´m (18 ft. lbs.)
torque.
(7) Tighten support bracket bolt 12 N´m (9 ft. lbs.)
torque.
(8) Connect electrical connector to pump (Fig. 64).
(9) Connect fuel line quick-connect fitting to fuel
supply line at rear of pump.
(10) Install starter motor. Refer to Starter Remov-
al/Installation in 8, Starting for procedures.
(11) Connect both negative battery cables at both
batteries.
(12) Bleed air at fuel supply line at side of fuel
injection pump. Refer to the Air Bleed Procedure.
(13) Start engine and check for leaks.
OVERFLOW VALVE
DESCRIPTION
The overflow valve is located on the side of the
injection pump (Fig. 65). It is also used to connect
the fuel return line (banjo fitting) to the fuel injection
pump.
OPERATION
Fuel volume from the fuel transfer (lift) pump will
always provide more fuel than the fuel injection
pump requires. The overflow valve (a check valve) is
used to route excess fuel through the fuel return line
and back to the fuel tank. Approximately 70% of sup-
plied fuel is returned to the fuel tank. The valve
opens at approximately 97 kPa (14 psi). If the check
valve within the assembly is sticking open, fuel
drainage of the injection pump could cause hard
starting.
If a Diagnostic Trouble Code (DTC) has been stored
for ªdecreased engine performance due to high injec-
tion pump fuel temperatureº, the overflow valve may
be stuck in closed position.
DIAGNOSIS AND TESTING - OVERFLOW VALVE
Fuel volume from the fuel transfer (lift) pump will
always provide more fuel than the fuel injection
pump requires. The overflow valve (a check valve) is
used to route excess fuel through the fuel return line
and back to the fuel tank. Approximately 70% of sup-
plied fuel is returned to the fuel tank. The valve is
located on the side of the injection pump (Fig. 66). It
is also used to connect the fuel return line (banjo fit-
ting) to the fuel injection pump. The valve opens at
approximately 97 kPa (14 psi). If the check valve
Fig. 65 Overflow Valve Location
1 - FUEL SUPPLY LINE
2 - FUEL RETURN LINE
3 - BANJO BOLT (TEST PORT FITTING)
4 - OVERFLOW VALVE
5 - BANJO FITTING
BR/BEFUEL DELIVERY - DIESEL 14 - 87
FUEL TRANSFER PUMP (Continued)

within the assembly is sticking, low engine power or
hard starting may result.
If a Diagnostic Trouble Code (DTC) has been stored
for ªdecreased engine performance due to high injec-
tion pump fuel temperatureº, the overflow valve may
be stuck in closed position.
A rubber tipped blow gun with regulated air line
pressure is needed for this test.
(1) Clean area around overflow valve and fuel
return line at injection pump before removal.
(2) Remove valve from pump and banjo fitting.
(3) Discard old sealing gaskets.
(4) Set regulated air pressure to approximately 97
kPa (14±16 psi).
(5) Using blow gun, apply pressure to overflow
valve inlet end (end that goes into injection pump).
(6) Internal check valve should release, and air
should pass through valve at 97 kPa (14±16 psi). If
not, replace valve.
(7) Reduce regulated air pressure to 10 psi and
observe valve. Valve should stay shut. If not, replace
valve.
(8) Install new sealing gaskets to valve.
(9) Install valve through banjo fitting and into
pump.
(10) Tighten to 30 N´m (24 ft. lbs.) torque.REMOVAL
The overflow valve (pressure relief valve) is located
at the outside of fuel injection pump (Fig. 67). It con-
nects the fuel return line (banjo fitting) to the pump.
The valve has no internal serviceable parts and must
be replaced as an assembly. Two sealing gaskets are
used. One gasket is located between pump and banjo
fitting. The other is located between the banjo fitting
and end of valve.
(1) Clean area around overflow valve and fuel
return line at injection pump before removal.
(2) Remove valve from pump and banjo fitting.
(3) Discard old sealing gaskets.
INSTALLATION
The overflow valve (pressure relief valve) is located
at the outside of fuel injection pump (Fig. 67). It con-
nects the fuel return line (banjo fitting) to the pump.
The valve has no internal serviceable parts and must
be replaced as an assembly. Two sealing gaskets are
used. One gasket is located between pump and banjo
fitting. The other is located between the banjo fitting
and end of valve.
(1) Install new sealing gaskets to valve.
(2) Install valve through banjo fitting and into
pump.
(3) Tighten to 30 N´m (24 ft. lbs.) torque.
Fig. 66 Overflow Valve Location
1 - FUEL SUPPLY LINE
2 - FUEL RETURN LINE
3 - BANJO BOLT (TEST PORT FITTING)
4 - OVERFLOW VALVE
5 - BANJO FITTING
Fig. 67 Overflow Valve Location
1 - FUEL SUPPLY LINE
2 - FUEL RETURN LINE
3 - BANJO BOLT (TEST PORT FITTING)
4 - OVERFLOW VALVE
5 - BANJO FITTING
14 - 88 FUEL DELIVERY - DIESELBR/BE
OVERFLOW VALVE (Continued)

WATER IN FUEL SENSOR
DESCRIPTION
The WIF sensor is located on the side of the fuel
filter/water separator canister (Fig. 68).
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 at the end of the intake manifold air heater
post-heat cycle.
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.
FUEL DRAIN MANIFOLD
DESCRIPTION
The fuel drain manifold is actually a rifled passage
within the cylinder head (Fig. 69).
OPERATION
When the engine is running, and during injection,
a small amount of fuel flows past the injector nozzle
and is not injected into the combustion chamber. This
fuel is used to lubricate the fuel injectors. Excess fuel
drains into the fuel drain manifold (or passage). Fuel
is drained from this passage into a line at the rear of
the cylinder head (Fig. 69). After exiting the cylinder
head, fuel is routed (returned) back to the fuel tank.
A ªTº is installed into the fuel return line (Fig. 69).
This ªTº is used to allow excess fuel from the injec-
tion pump to be returned into the fuel tank. A one-
way check valve within the overflow valve prevents
fuel (from the fuel drain manifold) from entering the
fuel injection pump.
Asmallamount of fuel is returned from the fuel
injectors, while alargeamount (about 70% of sup-
plied fuel) is returned from the fuel injection pump.
Fig. 68 Water-in-Fuel Sensor Location
1 - WATER-IN-FUEL (WIF) SENSOR
2 - FUEL FILTER/WATER SEPARATOR
3 - WIF SENSOR CONNECTOR
Fig. 69 Fuel Drain Manifold Passage
1 - REAR OF CYLINDER HEAD
2 - BANJO FITTING/BOLT
3 - FUEL RETURN TO TANK
4 - FUEL RETURN LINES
5 - FUEL RETURN LINE FROM PUMP OVERFLOW VALVE
6 - FUEL DRAIN MANIFOLD PASSAGE
7 - ªTº
BR/BEFUEL DELIVERY - DIESEL 14 - 89

REMOVAL
The fuel drain manifold (line) connects a fuel
return passage within the cylinder head to a ªTº fit-
ting on the fuel return line. It is located at the rear
of the cylinder head.
(1) Disconnect both negative battery cables at both
batteries.
(2) Remove starter motor. Refer to Group 8B for
procedures.
(3) Disconnect fitting at ªTº (Fig. 70).(4) Remove banjo bolt at rear of cylinder head.
Discard old sealing washers.
(5) Remove fuel line from vehicle.
(6) Clean connection at rear of cylinder head
before line installation.
INSTALLATION
The fuel drain manifold (line) connects a fuel
return passage within the cylinder head to a ªTº fit-
ting on the fuel return line. It is located at the rear
of the cylinder head.
Servicing fuel return components will not require
air bleeding.
(1) Using new sealing washers, assemble banjo
bolt to fuel line.
(2) Position line to engine and loosely tighten fas-
teners.
(3) Tighten banjo bolt to 24 N´m (18 ft. lbs.)
torque.
(4) Tighten fitting at ªTº to 12 N´m (106 in. lbs.)
torque.
(5) Install starter motor. Refer to 8, Starter for
procedures.
(6) Connect both negative battery cables at both
batteries.
Fig. 70 Fuel Return Line at Rear of Cylinder Head
1 - REAR OF CYLINDER HEAD
2 - BANJO FITTING/BOLT
3 - FUEL RETURN TO TANK
4 - FUEL RETURN LINES
5 - FUEL RETURN LINE FROM PUMP OVERFLOW VALVE
6 - FUEL DRAIN MANIFOLD PASSAGE
7 - ªTº
14 - 90 FUEL DELIVERY - DIESELBR/BE
FUEL DRAIN MANIFOLD (Continued)

FUEL INJECTION - DIESEL
TABLE OF CONTENTS
page page
FUEL INJECTION - DIESEL
DESCRIPTION - DIESEL FUEL INJECTION
SYSTEM............................91
DIAGNOSIS AND TESTING - BOOST
PRESSURE..........................93
SPECIFICATIONS
TORQUE - DIESEL ENGINE.............94
ACCELERATOR PEDAL POSITION SENSOR
DESCRIPTION.........................95
OPERATION...........................95
REMOVAL.............................95
INSTALLATION.........................97
FUEL INJECTOR
DESCRIPTION.........................97
OPERATION...........................98
DIAGNOSIS AND TESTINGÐFUEL INJECTOR
TEST...............................99
REMOVAL............................101
INSTALLATION........................102
FUEL INJECTION PUMP RELAY
DESCRIPTION........................103
OPERATION..........................103
FUEL TEMPERATURE SENSOR
DESCRIPTION........................104
OPERATION..........................104
INTAKE AIR HEATER
DESCRIPTION........................104OPERATION..........................104
REMOVAL............................104
INSTALLATION........................105
INTAKE AIR HEATER RELAY
DESCRIPTION........................105
OPERATION..........................105
REMOVAL............................106
INSTALLATION........................106
INTAKE AIR TEMPERATURE SENSOR
DESCRIPTION - DIESEL.................106
OPERATION - DIESEL..................106
REMOVAL - DIESEL....................107
INSTALLATION - DIESEL................107
MAP SENSOR
DESCRIPTION - DIESEL.................108
OPERATION - DIESEL..................108
REMOVAL - DIESEL....................108
INSTALLATION........................108
PTO SWITCH
DESCRIPTION
OPERATION........................108
THROTTLE CONTROL CABLE
REMOVAL............................109
INSTALLATION........................110
FUEL INJECTION - DIESEL
DESCRIPTION - DIESEL FUEL INJECTION
SYSTEM
The Engine Control Module (ECM) and Fuel Injec-
tion Pump Control Module (FPCM) are used prima-
rily for fuel system control. The ECM is a separate
replaceable component, while the FPCM is internal
to the fuel injection pump and is a non-serviceable
part. The ECM and FPCM are interconnected (wired
together) for fuel injection control.The Powertrain Control Module (PCM) is used to
regulate or control the A/C, charging and speed con-
trol systems. It is also used to partially control cer-
tain electronic automatic transmission components.
The PCM also has control over certain instrument
panel components.
Refer to either Powertrain Control Module (PCM)
or Engine Control Module (ECM) for additional infor-
mation. Refer to (Fig. 1) for a partial list of fuel sys-
tem components.
BR/BEFUEL INJECTION - DIESEL 14 - 91

Fig. 1 FUEL SYSTEM COMPONENTS - DIESEL
1 - ENGINE COOLANT TEMPERATURE (ECT) SENSOR 14 - FUEL SUPPLY LINE (LOW-PRESSURE, TO ENGINE)
2 - THROTTLE LEVER BELLCRANK AND APPS (ACCELERATOR
PEDAL POSITION SENSOR)15 - FUEL TRANSFER (LIFT) PUMP
3 - INTAKE MANIFOLD AIR HEATER/ELEMENTS 16 - OIL PRESSURE SENSOR
4 - HIGH-PRESSURE FUEL LINES 17 - FUEL FILTER/WATER SEPARATOR
5 - FUEL HEATER 18 - DRAIN TUBE
6 - FUEL PRESSURE TEST PORT 19 - WATER-IN-FUEL (WIF) SENSOR
7 - MAP (BOOST) SENSOR 20 - ENGINE CONTROL MODULE (ECM)
8 - FUEL INJECTORS 21 - FUEL PRESSURE TEST PORT
9 - FUEL INJECTOR CONNECTOR 22 - CAMSHAFT POSITION SENSOR (CMP)
10 - INTAKE AIR TEMPERATURE (IAT) SENSOR 23 - OVERFLOW VALVE
11 - FUEL DRAIN MANIFOLD 24 - FUEL INJECTION PUMP
12 - DRAIN VALVE 25 - FUEL HEATER TEMPERATURE SENSOR (THERMOSTAT)
13 - FUEL RETURN LINE (TO FUEL TANK)
14 - 92 FUEL INJECTION - DIESELBR/BE
FUEL INJECTION - DIESEL (Continued)

DIAGNOSIS AND TESTING - BOOST PRESSURE
Two pressure gauges attached at two different
points are required for this test.(1) Obtain two 6828 fuel pressure test gauges
(equivalent gauges are OK).Gauge Consistency
Test:Connect the gauges together to a common pres-
sure source and verify pressure consistency of both
gauges. Do this consistency test at approximately 206
kPa (30 psi). If pressures are different, they can still
be used for test. Note and record differences in pres-
sures before testing. Make adjustments as necessary.
(2) Remove 3/4º pipe plug fitting at rear of intake
manifold (Fig. 2). Temporarily replace this fitting
with fitting reducer to adapt to pressure gauge.
Note: This pipe plug is located to front of MAP
sensor. Do not remove plug to rear of MAP sen-
sor. This is a COOLANT passage plug.
(3) Loosen hose clamp and disconnect rubber sig-
nal line (Fig. 3) from 1/8º brass fitting at front of tur-
bocharger.
(4) Remove 1/8º brass fitting (Fig. 3) from turbo-
charger. Temporarily replace this fitting with a 1/8º
ªTº fitting to adapt to pressure gauge.
(5) Reattach signal line to temporary ªTº.
(6) Attach first pressure gauge to intake manifold
fitting.
(7) Attach second pressure gauge to ªTº fitting at
turbocharger.
Engine must be at rated RPM and full load for the
test.
If gauge pressure differential is greater than 3 psi
(6 in. Hg), check intercooler and associated piping for
restrictions, plugging or damage.
Maximum pressure at intake manifold (rated rpm
and load) is 36±37 in/hg   3 in/hg (17.7±18.2 psi  
1.5 psi).
Wastegate should open at no higher than 38.7
in/hg (19 psi) at wide open throttle, full load. If
wastegate is out of adjustment, a DTC may have
been set. Refer to Wastegate Adjustment in Engines
for adjustment procedures.
Fig. 2 Boost Pressure Test at Intake Manifold
1 - REAR OF INTAKE MANIFOLD
2 - 3/49PIPE PLUG
Fig. 3 Boost Pressure Test at Turbocharger
1 - TURBOCHARGER
2 - 1/89FITTING
3 - SIGNAL LINE
4 - WASTEGATE ACTUATOR
5 - CONTROL ROD
6 - OIL SUPPLY LINE
BR/BEFUEL INJECTION - DIESEL 14 - 93
FUEL INJECTION - DIESEL (Continued)

SPECIFICATIONS
TORQUE - DIESEL ENGINE
DESCRIPTION N m Ft. Lbs. In. Lbs.
Accelerator Pedal Position Sensor Bracket Bolts 12 9 105
Air Intake Housing Bolts 24 18 212
Banjo Fittings at top of Filter/Separator 24 18 212
Banjo Fittings at Fuel Return Lines 24 18 212
Banjo Fitting At Fuel Supply Line (Injector Pump) 24 18 212
Camshaft Position Sensor (CMP) Bolt 20 15 177
ECM Mounting Bolts 24 18 212
Engine Coolant Temperature (ECT) Sensor 14 10 124
Engine Lifting Bracket Bolts 77 57 681
Fuel Drain Manifold ªTº Fitting 12 9 106
Fuel Filter Canister Bracket Bolts 24 18 212
Fuel Filter Canister Mounting Nut 14 10 124
Fuel Filter Drain Valve Mounting Screws 3-5 2-4 30-40
Fuel Heater Screws 2-3 1-2 15-20
Fuel Injector Clamp Bolts 10 7 89
Fuel Pump Module Locknut 24-44 18-32 212-389
Fuel Tank Mounting Nuts 41 30 363
Fuel Transfer Pump Mounting Nuts 12 9 106
High-Pressure Fuel Line Fittings (at Injectors) 38 28 336
High-Pressure Fuel Line Fittings (at Pump) 24 18 212
High-Pressure Fuel Line Clamps-to-Intake Manifold 24 18 212
Hose Clamps at Intercooler Tube 8 6 72
Injection Pump-to-Injection Pump Gear Nut 170 125
Injection Pump Mounting Nuts 43 32 380
Intake Manifold Air Temperature (IAT) Sensor 14 10
Intake Manifold Air Heater Relay Bolts 4.5 40
Manifold Air Pressure (MAP) Sensor 14 10
PCM Mounting Bolts 4 35
Overflow Valve-to-Fuel Injection Pump 24 18
Water-In-Fuel (WIF) Sensor 2-3 15-20
14 - 94 FUEL INJECTION - DIESELBR/BE
FUEL INJECTION - DIESEL (Continued)