air filter DODGE RAM 2001 Service Manual PDF

bearing housing, routes the engine oil back to the
crankcase.
The most common turbocharger failure is bearing
failure related to repeated hot shutdowns with inad-
equate ªcool-downº periods. A sudden engine shut
down after prolonged operation will result in the
transfer of heat from the turbine section of the tur-
bocharger to the bearing housing. This causes the oil
to overheat and break down, which causes bearing
and shaft damage the next time the vehicle is
started.
Letting the engine idle after extended operation
allows the turbine housing to cool to normal operat-
ing temperature. The following chart should be used
as a guide in determining the amount of engine idle
time required to sufficiently cool down the turbo-
charger before shut down, depending upon the type
of driving and the amount of cargo.
REMOVAL
(1) Disconnect the battery negative cables.
(2) Raise vehicle on hoist.
(3) Disconnect the exhaust pipe from the turbo-
charger elbow (Fig. 22).
(4) Lower vehicle.
(5) Disconnect the turbocharger air inlet hose (Fig.
23).
(6) Disconnect the turbocharger oil supply line and
the oil drain tube from the turbocharger (Fig. 24).
(7) Disconnect the charge air cooler inlet pipe from
the turbocharger (Fig. 24).(8) Remove the turbocharger and gasket from the
exhaust manifold.
(9) If the turbocharger is not to be installed imme-
diately, cover the opening to prevent material from
entering into the manifold.
(10) If replacing the turbocharger, transfer the dis-
charge elbow and clamp to the new assembly.
(11) Clean and inspect the sealing surface.
Fig. 21 Turbocharger Oil Supply and Drain
1 - BEARINGS
2 - OIL SUPPLY (FROM FILTER HEAD)
3 - OIL RETURN (TO SUMP)
Fig. 22 Exhaust Pipe Removal/Installation
1 - EXHAUST PIPE
2 - TURBOCHARGER EXHAUST PIPE
Fig. 23 Turbocharger Air Inlet Hose
1 - AIR FILTER HOUSING COVER
2 - TURBOCHARGER
3 - AIR INLET TUBE
4 - HOSE CLAMP
5 - HINGE TABS
6 - FILTER MINDER
7 - CLIPS (4)
8 - TUBE ALIGNMENT NOTCHES
BR/BEEXHAUST SYSTEM 11 - 15
TURBOCHARGER (Continued)

(3)Pre-lube the turbocharger.Pour 50 to 60 cc
(2 to 3 oz.) clean engine oil in the oil supply line fit-
ting. Carefully rotate the turbocharger impeller by
hand to distribute the oil thoroughly.
(4) Install and tighten the oil supply line fitting
nut to 20 N´m (133 in. lbs.) torque.
(5) Position the charge air cooler inlet pipe to the
turbocharger. With the clamp in position, tighten the
clamp nut to 11 N´m (95 in. lbs.) torque.
(6) Position the air inlet hose to the turbocharger
(Fig. 23). Tighten the clamp to 11 N´m (95 in. lbs.)
torque.
(7) Raise vehicle on hoist.
(8) Connect the exhaust pipe to the turbocharger
(Fig. 22) and tighten the bolts to 34 N´m (25 ft. lbs.)
torque.
(9) Lower the vehicle.
(10) Connect the battery negative cables.
(11) Start the engine to check for leaks.
CHARGE AIR COOLER AND
PLUMBING
DESCRIPTION
The charge air system (Fig. 28) consists of the
charge air cooler piping, charge air cooler and intake
air grid heater.
The charge air cooler is a heat exchanger that uses
air flow from vehicle motion to dissipate heat from
the intake air. As the turbocharger increases air
pressure, the air temperature increases. Lowering
the intake air temperature increases engine effi-
ciency and power.
OPERATION
Intake air is drawn through the air cleaner and
into the turbocharger compressor housing. Pressur-
ized air from the turbocharger then flows forward
through the charge air cooler located in front of the
radiator. From the charge air cooler the air flows
back into the intake manifold.
REMOVAL
WARNING: IF THE ENGINE WAS JUST TURNED
OFF, THE AIR INTAKE SYSTEM TUBES MAY BE
HOT.
(1) Disconnect the battery negative cables.
(2) Remove the front bumper (Refer to 13 -
FRAMES & BUMPERS/BUMPERS/FRONT
BUMPER - REMOVAL).
Fig. 26 Measure Turbocharger Axial End Play
Fig. 27 Measure Turbocharger Bearing Radial
Clearance
1 - FEELER GAUGE
Fig. 28 Intake Air Circulation
1 - CHARGE AIR COOLER
2 - AIRFILTER
3 - TURBOCHARGER
BR/BEEXHAUST SYSTEM 11 - 17
TURBOCHARGER (Continued)

FUEL DELIVERY - GASOLINE
DESCRIPTION - FUEL DELIVERY SYSTEM
The fuel delivery system consists of:
²the fuel pump module containing the electric
fuel pump, fuel filter/fuel pressure regulator, rollover
valve (certain modules), fuel gauge sending unit (fuel
level sensor) and a separate fuel filter located at bot-
tom of pump module
²fuel tubes/lines/hoses
²quick-connect fittings
²fuel injector rail
²fuel injectors
²fuel tank
²fuel tank filler/vent tube assembly
²fuel tank filler tube cap
²accelerator pedal
²throttle cable
OPERATION - FUEL DELIVERY SYSTEM
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 with any gas-
oline powered engine.
The fuel tank assembly consists of: the fuel tank,
fuel pump module assembly, fuel pump module lock-
nut/gasket and rollover valve(s) (refer to 25, Emis-
sion Control System for rollover valve 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 25, 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.
DIAGNOSIS AND TESTING - FUEL PRESSURE
LEAK DOWN TEST
Use this test in conjunction with the Fuel Pump
Pressure Test and Fuel Pump Capacity Test.
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. Afterthe 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.
Abnormally long periods of cranking to restart a
hotengine that has been shut down for a short
period of time may be caused by:
²Fuel pressure bleeding past a fuel injector(s).
²Fuel pressure bleeding past the check valve in
the fuel pump module.
(1) Disconnect the fuel inlet line at fuel rail. Refer
to Fuel Tubes/Lines/Hoses and Clamps for proce-
dures. On some engines, air cleaner housing removal
may be necessary before fuel line disconnection.
(2) 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.
(3) Connect correct Fuel Line Pressure Test
Adapter Tool Hose between disconnected fuel line
and fuel rail (Fig. 1).
Fig. 1 Connecting Adapter ToolÐTypical
1 - VEHICLE FUEL LINE
2 - TEST PORT ªTº
3 - SPECIAL TOOL 6923, 6631, 6541 OR 6539
4 - FUEL PRESSURE TEST GAUGE
5 - FUEL LINE CONNECTION AT RAIL
6 - FUEL RAIL
14 - 2 FUEL DELIVERY - GASOLINEBR/BE

INSTALLATION
The fuel gauge sending unit (fuel level sensor) and
float assembly is located on the side of fuel pump
module (Fig. 9). The fuel pump module is located
inside of fuel tank.
(1) Position sending unit into tracks. Note wire
routing.
(2) Push unit on tracks until lock tab snaps into
notch.
(3) Connect 2 sending unit wires into 4±way con-
nector and install locking collar.
(4) Connect 4±way electrical connector to module.
(5) Install fuel pump module. Refer to Fuel Pump
Module Removal/Installation.
(6) Install fuel tank. Refer to Fuel Tank±All
Engines in the Removal/Installation section.
FUEL LINES
DESCRIPTION
Also refer to Quick-Connect Fittings.
WARNING: THE FUEL SYSTEM IS UNDER A CON-
STANT PRESSURE (EVEN WITH THE ENGINE OFF).
BEFORE SERVICING ANY FUEL SYSTEM HOSES, FIT-
TINGS OR LINES, THE FUEL SYSTEM PRESSURE
MUST BE RELEASED. REFER TO THE FUEL SYSTEM
PRESSURE RELEASE PROCEDURE IN THIS GROUP.
The lines/tubes/hoses used on fuel injected vehicles
are of a special construction. This is due to the
higher fuel pressures and the possibility of contami-
nated fuel in this system. If it is necessary to replace
these lines/tubes/hoses, only those marked EFM/EFI
may be used.
If equipped:The hose clamps used to secure rub-
ber hoses on fuel injected vehicles are of a special
rolled edge construction. This construction is used to
prevent the edge of the clamp from cutting into the
hose. Only these rolled edge type clamps may be
used in this system. All other types of clamps may
cut into the hoses and cause high-pressure fuel leaks.
Use new original equipment type hose clamps.
FUEL PUMP
DESCRIPTION
The fuel pump is located inside of the fuel pump
module. A 12 volt, permanent magnet, electric motor
powers the fuel pump.
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.
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 graduated 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.
BR/BEFUEL DELIVERY - GASOLINE 14 - 9
FUEL LEVEL SENDING UNIT / SENSOR (Continued)

(7) Connect two mounting straps and mounting
strap nuts.
(8) Tighten strap nuts to 41 N´m (30 ft. lbs.)
torque. Do not over tighten retaining strap nuts.
(9) Remove transmission jack.
(10) Connect fuel filler tube assembly to body.
(11) If equipped, connect grounding wire (strap)
and screw.
(12) Refill fuel tank and inspect all hoses and lines
for leaks.
(13)
Connect negative battery cable(s) to battery(s).
INLET FILTER
REMOVAL
The fuel pump inlet filter (strainer) is located on
the bottom of the fuel pump module (Fig. 40). The
fuel pump module is located inside of fuel tank.
(1) Remove fuel tank. Refer to Fuel Tank Removal/
Installation.
(2) Remove fuel pump module. Refer to Fuel Pump
Module Removal/Installation.
(3) Remove filter by carefully prying 2 lock tabs at
bottom of module with 2 screwdrivers. Filter is
snapped to module.
(4) Clean bottom of pump module.
INSTALLATION
The fuel pump inlet filter (strainer) is located on
the bottom of the fuel pump module (Fig. 40). The
fuel pump module is located inside of fuel tank.
(1) Snap new filter to bottom of module. Be sure
o-ring is in correct position.(2) Install fuel pump module. Refer to Fuel Pump
Module Removal/Installation.
(3) Install fuel tank. Refer to Fuel Tank Removal/
Installation.
QUICK CONNECT FITTING
DESCRIPTION
Different types of quick-connect fittings are used to
attach various fuel system components, lines and
tubes. These are: a single-tab type, a two-tab type or
a plastic retainer ring type. Some are equipped with
safety latch clips. Some may require the use of a spe-
cial tool for disconnection and removal. Refer to
Quick-Connect Fittings Removal/Installation for more
information.
CAUTION: The interior components (o-rings, clips)
of quick-connect fittings are not serviced sepa-
rately, but new plastic spacers are available for
some types. If service parts are not available, do
not attempt to repair the damaged fitting or fuel line
(tube). If repair is necessary, replace the complete
fuel line (tube) assembly.
STANDARD PROCEDURES - QUICK-CONNECT
FITTINGS
Also refer to Fuel Tubes/Lines/Hoses and Clamps.
Different types of quick-connect fittings are used to
attach various fuel system components, lines and
tubes. These are: a single-tab type, a two-tab type or
a plastic retainer ring type. Safety latch clips are
used on certain components/lines. Certain fittings
may require use of a special tool for disconnection.
DISCONNECTING
WARNING: THE FUEL SYSTEM IS UNDER A CON-
STANT PRESSURE (EVEN WITH ENGINE OFF).
BEFORE SERVICING ANY FUEL SYSTEM HOSE,
FITTING OR LINE, FUEL SYSTEM PRESSURE MUST
BE RELEASED. REFER TO FUEL SYSTEM PRES-
SURE RELEASE PROCEDURE.
CAUTION: The interior components (o-rings, spac-
ers) of some types of quick-connect fitting are not
serviced separately. If service parts are not avail-
able, do not attempt to repair a damaged fitting or
fuel line. If repair is necessary, replace complete
fuel line assembly.
(1) Perform fuel pressure release procedure. Refer
to Fuel Pressure Release Procedure.
(2) Disconnect negative battery cable from battery.
Fig. 40 Fuel Pump Inlet Filter
1 - FUEL PUMP INLET FILTER
2 - LOCK TABS (2)
3 - FUEL PUMP MODULE (BOTTOM)
14 - 22 FUEL DELIVERY - GASOLINEBR/BE
FUEL TANK (Continued)

REMOVAL - 8.0L
The crankshaft position sensor is located on the
right-lower side of the cylinder block, forward of the
right engine mount, just above the oil pan rail (Fig.
28).
(1) Raise and support vehicle.
(2) Disconnect sensor pigtail harness from main
engine wiring harness.
(3) Remove sensor mounting bolt (Fig. 29).
(4) Cut plastic tie strap (Fig. 28) securing sensor
pigtail harness to side of engine block.
(5) Carefully pry sensor from cylinder block in a
rocking action with two small screwdrivers.
(6) Remove sensor from vehicle.
(7) Check condition of sensor o-ring (Fig. 30).
INSTALLATION - 3.9L/5.2L/5.9L
(1) Position crankshaft position sensor to engine.
(2) Install mounting bolts and tighten to 8 N´m (70
in. lbs.) torque.
(3) Connect main harness electrical connector to
sensor.
(4) Install air cleaner tube.
INSTALLATION - 8.0L
The crankshaft position sensor is located on the
right-lower side of the cylinder block, forward of the
right engine mount, just above the oil pan rail (Fig.
28).(1) Apply a small amount of engine oil to sensor
o-ring (Fig. 30).
(2) Install sensor into cylinder block 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 cylinder block
(Fig. 29). If sensor is not flush, damage to sensor
mounting tang may result.
(3) Install mounting bolt and tighten to 8 N´m (70
in. lbs.) torque.
(4) Connect sensor pigtail harness to main engine
wiring harness
Fig. 28 Crankshaft Position Sensor LocationÐ8.0L
V-10 Engine
1 - CRANKSHAFT POSITION SENSOR
2 - HOLE
3 - OIL FILTER
4 - PLASTIC TIE STRAP
5 - PIGTAIL HARNESS
Fig. 29 Sensor Removal/InstallationÐ8.0L V-10
Engine
1 - CRANKSHAFT POSITION SENSOR
2 - MOUNTING BOLT
3 - SENSOR POSITIONED FLUSH TO CYLINDER BLOCK
Fig. 30 Sensor O-RingÐ8.0L V-10 Engine
1 - CRANKSHAFT POSITION SENSOR O-RING
2 - ELECTRICAL CONNECTOR
3 - PIGTAIL HARNESS
14 - 40 FUEL INJECTION - GASOLINEBR/BE
CRANKSHAFT POSITION SENSOR (Continued)

WARNING: THE EXHAUST MANIFOLD, EXHAUST
PIPES AND CATALYTIC CONVERTER BECOME
VERY HOT DURING ENGINE OPERATION. ALLOW
ENGINE TO COOL BEFORE REMOVING OXYGEN
SENSOR.
(1) Raise and support the vehicle.
(2) Disconnect the wire connector from the O2S
sensor.
CAUTION: When disconnecting the sensor electrical
connector, do not pull directly on wire going into
sensor.
(3) Remove the O2S sensor with an oxygen sensor
removal and installation tool.
INSTALLATION
Threads of new oxygen sensors are factory coated
with anti-seize compound to aid in removal.DO
NOT add any additional anti-seize compound to
the threads of a new oxygen sensor.
(1) Install the O2S sensor. Tighten to 30 N´m (22
ft. lbs.) torque.
(2) Connect the O2S sensor wire connector.
(3) Lower the vehicle.
PTO SWITCH
DESCRIPTION
This Powertrain Control Module (PCM) input is
used only on models equipped with aftermarket
Power Take Off (PTO) units.
OPERATION
The input is used only to tell the PCM that the
PTO has been engaged. The PCM will disable (tem-
porarily shut down) certain OBD II diagnostic trou-
ble codes when the PTO is engaged.
When the aftermarket PTO switch has been
engaged, a 12V + signal is sent through circuit G113
to PCM pin A13. The PCM will then sense and deter-
mine that the PTO has been activated.
THROTTLE BODY
DESCRIPTION
The throttle body is located on the intake manifold.
Fuel does not enter the intake manifold through the
throttle body. Fuel is sprayed into the manifold by
the fuel injectors.
OPERATION
Filtered air from the air cleaner enters the intake
manifold through the throttle body. The throttle body
contains an air control passage controlled by an Idle
Air Control (IAC) motor. The air control passage is
used to supply air for idle conditions. A throttle valve
(plate) is used to supply air for above idle conditions.
Certain sensors are attached to the throttle body.
The accelerator pedal cable, speed control cable and
transmission control cable (when equipped) are con-
nected to the throttle body linkage arm.
A (factory adjusted) set screw is used to mechani-
cally limit the position of the throttle body throttle
plate.Never attempt to adjust the engine idle
speed using this screw.All idle speed functions are
controlled by the PCM.
REMOVAL - 3.9L/5.2L/5.9L
A (factory adjusted) set screw is used to mechani-
cally limit the position of the throttle body throttle
plate.Never attempt to adjust the engine idle
speed using this screw.All idle speed functions are
controlled by the powertrain control module (PCM).
(1) Remove the air cleaner.
(2) Disconnect throttle body electrical connectors
at MAP sensor, IAC motor and TPS (Fig. 41).
(3) Remove vacuum line at throttle body.
(4) Remove all control cables from throttle body
(lever) arm. Refer to the Accelerator Pedal and Throt-
tle Cable section of this group for additional informa-
tion.
Fig. 41 Sensor Electrical ConnectorsÐ3.9L/5.2L/5.9L
EnginesÐTypical
1 - MAP SENSOR
2 - IDLE AIR CONTROL MOTOR
3 - THROTTLE POSITION SENSOR
14 - 48 FUEL INJECTION - GASOLINEBR/BE
O2 SENSOR (Continued)

FUEL DELIVERY - DIESEL
TABLE OF CONTENTS
page page
FUEL DELIVERY - DIESEL
DESCRIPTION...........................54
OPERATION.............................56
DIAGNOSIS AND TESTING.................56
AIR IN FUEL SYSTEM...................56
FUEL SUPPLY RESTRICTIONS............56
STANDARD PROCEDURE..................56
WATER DRAINING AT FUEL FILTER........56
CLEANING FUEL SYSTEM PARTS..........57
AIR BLEED............................57
SPECIFICATIONS........................58
SPECIAL TOOLS.........................59
FUEL FILTER / WATER SEPARATOR
DESCRIPTION...........................59
OPERATION.............................59
REMOVAL..............................60
INSTALLATION...........................61
FUEL HEATER
DESCRIPTION...........................62
OPERATION.............................62
DIAGNOSIS AND TESTING.................62
FUEL HEATER.........................62
REMOVAL..............................63
FUEL HEATER RELAY
DESCRIPTION...........................63
OPERATION.............................63
DIAGNOSIS AND TESTING.................64
FUEL HEATER RELAY...................64
REMOVAL..............................65
INSTALLATION...........................65
FUEL INJECTION PUMP
DESCRIPTION...........................65
OPERATION.............................66
DIAGNOSIS AND TESTING.................66
FUEL INJECTION PUMP TIMING...........66
REMOVAL..............................68
INSTALLATION...........................71
FUEL INJECTION PUMP DATA PLATE
SPECIFICATIONS........................73FUEL LEVEL SENDING UNIT / SENSOR
DESCRIPTION...........................73
OPERATION.............................73
FUEL LINES
DESCRIPTION...........................73
OPERATION.............................74
DIAGNOSIS AND TESTING.................74
HIGH-PRESSURE FUEL LINE LEAK.........74
REMOVAL..............................75
INSTALLATION...........................77
FUEL TANK
DESCRIPTION...........................78
FUEL TANK MODULE
DESCRIPTION...........................78
OPERATION.............................78
REMOVAL..............................78
INSTALLATION...........................79
FUEL TRANSFER PUMP
DESCRIPTION...........................79
OPERATION.............................79
DIAGNOSIS AND TESTING.................80
FUEL TRANSFER PUMP PRESSURE........80
REMOVAL..............................83
INSTALLATION...........................83
OVERFLOW VALVE
DESCRIPTION...........................83
OPERATION.............................83
DIAGNOSIS AND TESTING.................84
OVERFLOW VALVE.....................84
REMOVAL..............................84
INSTALLATION...........................85
WATER IN FUEL SENSOR
DESCRIPTION...........................85
OPERATION.............................85
REMOVAL..............................85
FUEL DRAIN MANIFOLD
DESCRIPTION...........................86
OPERATION.............................86
REMOVAL..............................86
INSTALLATION...........................86
FUEL DELIVERY - DIESEL
DESCRIPTION - DIESEL FUEL DELIVERY
SYSTEM
The fuel system on the Cummins 24 valveÐTurbo
Diesel Engine uses anelectronicfuel injection
pump with three control modules.Also refer to the Powertrain Control Module (PCM)
or Engine Control Module sections.
Some fuel system components are shown in (Fig.
1).
The fuel delivery system consists of the:
²Accelerator pedal
²Air cleaner housing/element
²Fuel drain manifold (passage)
14 - 54 FUEL DELIVERY - DIESELBR/BE

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)
BR/BEFUEL DELIVERY - DIESEL 14 - 55
FUEL DELIVERY - DIESEL (Continued)

²Fuel filter/water separator
²Fuel heater
²Fuel heater relay
²Fuel transfer (lift) pump
²Fuel injection pump
²Fuel injectors
²Fuel heater temperature sensor
²Fuel tank
²Fuel tank filler/vent tube assembly
²Fuel tank filler tube cap
²Fuel tank module containing the rollover valve,
fuel gauge sending unit (fuel level sensor) and a sep-
arate fuel filter located at bottom of tank module
²Fuel tubes/lines/hoses
²High-pressure fuel injector lines
²In-tank fuel filter (at bottom of fuel tank mod-
ule)
²Low-pressure fuel supply lines
²Low-pressure fuel return line
²Overflow valve
²Quick-connect fittings
²Throttle cable
²Water draining
OPERATION
WARNING: HIGH-PRESSURE FUEL LINES DELIVER
DIESEL FUEL UNDER EXTREME PRESSURE FROM
THE INJECTION PUMP TO THE FUEL INJECTORS.
THIS MAY BE AS HIGH AS 120,000 KPA (17,405
PSI). 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 - AIR IN FUEL
SYSTEM
Air will enter the fuel system whenever fuel supply
lines, separator filters, injection pump, high-pressure
lines or injectors are removed or disconnected. Air
trapped in the fuel system can result in hard start-
ing, a rough running engine, engine misfire, low
power, excessive smoke and fuel knock. After service
is performed, air must be bled from the system
before starting the engine.Inspect the fuel system from the fuel transfer
pump to the injectors for loose connections. Leaking
fuel is an indicator of loose connections or defective
seals. Air can also enter the fuel system between the
fuel tank and the transfer pump. Inspect the fuel
tank and fuel lines for damage that might allow air
into the system.
For air bleeding, refer to the Air Bleed Procedure.
DIAGNOSIS AND TESTING - FUEL SUPPLY
RESTRICTIONS
LOW-PRESSURE LINES
Fuel supply line restrictions or a defective fuel
transfer pump can cause starting problems and pre-
vent engine from accelerating. The starting problems
include; low power and/or white fog like exhaust.
Test all fuel supply lines for restrictions or block-
age. Flush or replace as necessary. Bleed fuel system
of air once a fuel supply line has been replaced. Refer
to Air Bleed Procedure for procedures.
To test for fuel line restrictions, a vacuum restric-
tion test may be performed. Refer to Fuel Transfer
Pump Pressure Test.
HIGH-PRESSURE LINES
Restricted (kinked or bent) high-pressure lines can
cause starting problems, poor engine performance,
engine mis-fire and white smoke from exhaust.
Examine all high-pressure lines for any damage.
Each radius on each high-pressure line must be
smooth and free of any bends or kinks.
Replace damaged, restricted or leaking high-pres-
sure fuel lines with correct replacement line.
CAUTION: All high-pressure fuel lines must be
clamped securely in place in holders. 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 line is kinked or bent, it
must be replaced. Use only recommended lines
when replacement of high-pressure fuel line is nec-
essary.
STANDARD PROCEDURES - WATER DRAINING
AT FUEL FILTER
Refer to Fuel Filter/Water Separator removal/in-
stallation for procedures.
14 - 56 FUEL DELIVERY - DIESELBR/BE
FUEL DELIVERY - DIESEL (Continued)