Page 2337 of 5267
4.7L V-8
The TPS (2) is located on the throttle body.
1. Remove air duct and tube at throttle body.
2. Disconnect TPS electrical connector.
3. Remove two TPS mounting bolts (screws).
4. Remove TPS from throttle body.
5.7L V-8
The 5.7L V-8 engine does not use a separate Throttle Position Sensor (TPS) on the throttle body.
8.3L - SRT-10
The TPS is attached to the throttle body.
1. Disconnect the TPS electrical connector.
2. Remove the TPS mounting screws.
3. Remove the TPS.
Page 2338 of 5267
INSTALLATION
3.7L V-6
The Throttle Position Sensor (TPS) (1) is mounted to
the throttle body.
The throttle shaft end of throttle body slides into a
socket in TPS. The TPS must be installed so that it
can be rotated a few degrees. (If sensor will not
rotate, install sensor with throttle shaft on other side of
socket tangs). The TPS will be under slight tension
when rotated.
1. Install TPS and retaining screws.
2. Tighten screws to 7 Nꞏm (60 in. lbs.) torque.
3. Connect TPS electrical connector to TPS.
4. Manually operate throttle (by hand) to check for
any TPS binding before starting engine.
5. Install air cleaner tube to throttle body.
Page 2339 of 5267
4.7L V-8
The throttle shaft end of throttle body (5) slides into a
socket in TPS. The TPS must be installed so that it
can be rotated a few degrees. If sensor will not rotate,
install sensor with throttle shaft on other side of socket
tangs. The TPS will be under slight tension when
rotated.
1. Install TPS and two retaining bolts.
2. Tighten bolts to 7 Nꞏm (60 in. lbs.) torque.
3. Manually operate throttle control lever by hand to
check for any binding of TPS.
4. Connect TPS electrical connector to TPS.
5. Install air duct/air box to throttle body.
Page 2340 of 5267
8.3L - SRT-10
The TPS is attached to the throttle body.
The throttle shaft end of the throttle body slides into a
socket in the TPS. When indexed correctly, the TPS
can rotate a few degrees to line up the mounting
screw holes with the screw holes in the throttle body.
If the sensor will not rotate into place, install the sen-
sor with the throttle shaft on the other side of the
socket tangs. The TPS has slight tension when rotated
to align the mounting holes.
1. Install TPS and mounting screws.
2. Attach electrical connector to the TPS.
Page 2341 of 5267

page page
FUEL DELIVERY - DIESEL
DESCRIPTION - DIESEL FUEL SYSTEM ....... 105
STANDARD PROCEDURE
WATER DRAINING AT FUEL FILTER ......... 106
CLEANING FUEL SYSTEM PARTS .......... 106
FUEL SYSTEM PRIMING................... 106
DRAINING FUEL TANK - DIESEL............ 107
SPECIFICATIONS
FUEL INJECTOR FIRING ORDER - DIESEL . . 107
TORQUE .................................. 107
SPECIAL TOOLS
DIESEL FUEL SYSTEM . .................... 109
FILTER - FUEL / WATER SEPARATOR
DESCRIPTION ............................... 111
OPERATION ................................. 111
REMOVAL ................................... 111
INSTALLATION .............................. 113
HEATER-FUEL
DESCRIPTION ............................... 115
OPERATION ................................. 115
DIAGNOSIS AND TESTING
FUEL HEATER ............................. 115
REMOVAL ................................... 116
PUMP - FUEL INJECTION
DESCRIPTION ............................... 117
OPERATION ................................. 117
DIAGNOSIS AND TESTING
FUEL INJECTION PUMP TIMING ............ 117
REMOVAL ................................... 117
INSTALLATION .............................. 120
SENSOR - FUEL LEVEL SENDING UNIT
DESCRIPTION ............................... 124
OPERATION ................................. 124
REMOVAL
REMOVAL/INSTALLATION .................. 124
LINES - FUEL
DESCRIPTION ............................... 125
OPERATION ................................. 125DIAGNOSIS AND TESTING
HIGH-PRESSURE FUEL LINE LEAKS........ 125
REMOVAL ................................... 126
INSTALLATION .............................. 127
SENSOR - FUEL PRESSURE
DESCRIPTION ............................... 129
OPERATION ................................. 129
REMOVAL ................................... 129
INSTALLATION .............................. 129
VALVE - FUEL PRESSURE LIMITING
DESCRIPTION ............................... 130
OPERATION ................................. 130
REMOVAL ................................... 130
INSTALLATION .............................. 131
TA N K - F U E L
DESCRIPTION ............................... 132
REMOVAL ................................... 132
INSTALLATION .............................. 133
MODULE - FUEL TANK
DESCRIPTION ............................... 134
OPERATION ................................. 134
REMOVAL ................................... 134
INSTALLATION .............................. 134
PUMP - FUEL TRANSFER
DESCRIPTION ............................... 136
OPERATION ................................. 136
REMOVAL ................................... 136
INSTALLATION .............................. 136
VALVE - CASCADE OVERFLOW
DESCRIPTION ............................... 137
OPERATION ................................. 137
SENSOR-WATER IN FUEL
DESCRIPTION ............................... 138
OPERATION ................................. 138
REMOVAL ................................... 138
CIRCUIT - FUEL DRAIN
OPERATION ................................. 139
Page 2342 of 5267

FUEL DELIVERY - DIESEL
DESCRIPTION - DIESEL FUEL SYSTEM
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
160,000 kpa (23,206 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.
The fuel system used on the Cummins engine is an electronically controlled, Bosch HPCR (High-Pressure Common
Rail) system. The HPCR system consists of five main components:
Electric Fuel Transfer (lift) Pump Located in the Fuel Tank
Fuel Pump/Gear Pump (attached to fuel injection pump)
High-Pressure Fuel Injection Pump
Fuel Injection Rail
Fuel Injectors
Also to be considered as part of the overall fuel system are:
Accelerator Pedal
Air Cleaner Housing/Element
Check Valve Banjo Fitting at Rear of Cylinder Head
Fuel Connector Tubes
Fuel Drain Manifold (passage)
Fuel Drain Valve (at filter)
Fuel Filter/Water Separator
Fuel Heater
Fuel Heater Relay
Fuel Transfer Pump Relay
Fuel Level (gauge) Sending Unit
Fuel Pressure Limiting Valve
Fuel Tank
Fuel Tank Module (containing a fuel gauge sending unit, separate fuel filter located at bottom of tank module,
and fuel transfer pump)
Fuel Tank Filler/Vent Tube Assembly
Fuel Tank Filler Tube Cap
Fuel Tubes/Lines/Hoses
High-Pressure Fuel Injector Lines
In-Tank Fuel Filter (at bottom of fuel tank module)
Low-Pressure Fuel Supply Lines
Low-Pressure Fuel Return Lines
Overflow Valve
Quick-Connect Fuel Line Fittings
Accelerator Pedal Position Sensor (APPS) Located in Cab
Water Draining (maintenance)
Water-In-Fuel (WIF) Sensor
Screened Banjo Bolt (22)
The fuel injection pump supplies high pressure to the fuel rail independent of engine speed. This high pressure fuel
is then accumulated in the fuel rail. High pressure fuel is constantly supplied to the injectors by the fuel rail. The
Engine Control Module (ECM) controls the fueling and timing of the engine by actuating the injectors.
Page 2343 of 5267

Fuel enters the system from the electric fuel transfer (lift) pump, which is located inside of the fuel tank and attached
to the fuel tank module (the fuel transfer pump is no longer attached to the engine). Fuel is forced through the fuel
filter element and then enters the Fuel Pump/Gear Pump, which is attached to the rear of the fuel injection pump.
The Fuel Pump/Gear Pump is a low-pressure pump and produce pressures ranging from 551.5 kpa (80 psi) to 1241
kpa (180) psi. Fuel then enters the fuel injection pump. Low pressure fuel is then supplied to the FCA (Fuel Control
Actuator).
The FCA is an electronically controlled solenoid valve. The ECM controls the amount of fuel that enters the high-
pressure pumping chambers by opening and closing the FCA based on a demanded fuel pressure. The FPS (Fuel
Pressure Sensor) on the fuel rail monitors the actual fuel pressure and provides it as an input to the ECM. When
the actuator is opened, the maximum amount of fuel is being supplied to the fuel injection pump. Any fuel that does
not enter the injection pump is directed to the overflow valve. The overflow valve regulates how much excess fuel
is used for lubrication of the pump and how much is returned to the tank through the drain manifold.
Fuel entering the injection pump is pressurized to between 300-1600 bar (4351-23,206 psi) by three radial pumping
chambers. The pressurized fuel is then supplied to the fuel rail.
STANDARD PROCEDURE
WATER DRAINING AT FUEL FILTER
Refer to Fuel Filter/Water Separatorremoval/installation for procedures.
CLEANING FUEL SYSTEM PARTS
CAUTION: Cleanliness cannot be overemphasized when handling or replacingdieselfuelsystemcompo-
nents. 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 possible 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. Capor cover any open part after
disassembly. Before assembly, examine each part for dirt, grease or othercontaminants and clean if nec-
essary. When installing new parts, lubricate them with clean engine oil orclean diesel fuel only.
FUEL SYSTEM PRIMING
A certain amount of air becomes trappedin the fuel system when fuel system components on the supply and/or
high-pressure side are serviced or replaced. Fuel system priming is accomplished using the electric fuel transfer (lift)
pump.
Servicing or replacing fuel system components will not require fuel systempriming.
The fuel transfer (lift) pump is self-priming: When the key is first turnedon (without cranking engine), the pump
operates for approximately 1 to 2 second and then shuts off (Note: When ambient temperatures are cold enough to
cause the intake air heaters to operate, the fuel lift pump will operate during the entire intake air pre-heat cycle).
The pump will also operate for up to 25 seconds after the starter is quickly engaged, and then disengaged without
allowing the engine to start. The pump shuts off immediately if the key is onand the engine stops running.
1. Turn key to CRANK position and quickly release key to ON position before engine starts. This will operate fuel
transfer pump for approximately 25 seconds.
2. Crank engine. If the engine does not start after 25 seconds, turn key to OFF position, and leave it off for at least
5 seconds. Repeat previous step until engine starts.
3. Fuel system priming is now completed.
4. Attempt to start engine. If engine will not start, proceed to following steps.When engine does start, it may run
erratically and be noisy for a few minutes. This is a normal condition.
CAUTION: Do not engage the starter motor for more than 30 seconds at a time. Allow two minutes between
cranking intervals.
5. Perform previous fuel priming procedure steps using fuel transfer pump. Be sure fuel is present at fuel tank.
6. Crank the engine for 30 seconds at a time to allow fuel system to prime.
Page 2344 of 5267

WARNING: The fuel injection pump supplies extremely high fuel pressure toeach individual injector
through the high-pressure lines. Fuel under this amount of pressure can penetrate the skin and cause per-
sonal injury. Wear safety goggles and adequate protective clothing. Do not loosen fuel fittings while engine
is running.
WARNING: Engine may start while cranking starter motor.
DRAINING FUEL TANK - DIESEL
Due to a one-way check valve installed into the fuel fill opening fitting atthe tank, the tank cannot be drained con-
ventionally at the fill cap.
1. Raise vehicle.
2. If vehicle is equipped with 4 doors and a 6 foot (short) box, remove left-rear tire/wheel.
3. Thoroughly clean area at top of fuel tank around fuel tank module.
4. Loosen clamp and disconnect rubber fuel fill hose at tank.
5. Drain fuel tank by attaching drain hose from an approved diesel fuel draining station to the fuel fill fitting of tank.
SPECIFICATIONS
FUEL INJECTOR FIRING ORDER - DIESEL
1–5–3–6–2–4
TORQUE
DESCRIPTION N-m Ft. Lbs. In. Lbs.
Crankshaft Position
Sensor980
Camshaft Position Sensor 9 - 80
Engine Coolant
Temperature Sensor18 13 160
Rear Engine Lift Bracket
Bolts77 56 -
Fuel Connector Nut at
Cylinder Head50 37 -
Fuel Filler Hose Clamp at
Ta n k3-27
Fuel Filler Housing-to-
Body Screws2-17
Fuel Filter Lid 34 25 -
Fuel Filter Drain Valve
Screws1.5 - 14
Fuel Heater Element
Screws1.5 - 14
Fuel Line Banjo Fitting
Bolts24 18 -
Screened Banjo Bolt 24 18 -
Fuel Line Banjo Fitting
Bolts at Fuel Filter
Housing24 18 -