Login- Download PDF Manual
-
the throttle body (Fig. 56), or (Fig. 57).
(1) Remove air resonator tube at throttle body. (2) Disconnect TPS electrical connector. (3) Remove 2 TPS mounting screws. (4) Remove TPS.
4.7L V-8
The TPS is located on the throttle body (Fig. 58). (1) Remove air duct and tube at throttle body. (2) Disconnect TPS electrical connector. (3) Remove two TPS mounting bolts (screws) (Fig.
58).
(4) Remove TPS from throttle body.
5.7L V-8
The 5.7L V-8 engine does not use a separate Throt-
tle Position Sensor (TPS) on the throttle body.
5.9L V-8
The TPS is located on the side of the throttle body
(Fig. 59).
(1) Remove air intake tube at throttle body. (2) Disconnect TPS electrical connector. (3) Remove two TPS mounting bolts (Fig. 59). (4) Remove TPS from throttle body.
Fig.56TPSLOCATION-3.7LV-6
1 - THROTTLE POSITION SENSOR (TPS) 2 - MOUNTING SCREWS 3 - IDLE AIR CONTROL MOTOR (IAC) 4 - MOUNTING SCREWS
Fig.57TPSINSTALLATION-3.7V-6
1 - THROTTLE BODY 2 - TPS 3 - THROTTLE BODY SHAFT 4 - SOCKET LOCATING TANGS
8.0L V-10
The TPS is located on the side of the throttle body
(Fig. 60).
(1) Remove air plenum. (2) Disconnect TPS electrical connector.
FUEL INJECTION - GAS
14 - 54
THROTTLE POSITION SENSOR (Continued)DR
Fig.58TPSLOCATION-4.7L
1 - THROTTLE BODY 2 - TPS 3 - IAC MOTOR 4 - IAT SENSOR 5 - MOUNTING SCREWS
Fig.59TPSLOCATION-5.9LV-8
1 - THROTTLE POSITION SENSOR 2 - MOUNTING SCREWS
(3) Remove two TPS mounting bolts (Fig. 60). (4) Remove TPS from throttle body.
Fig.60TPSMOUNTINGBOLTS-8.0LV-10
1 - MOUNTING BOLTS (2) 2 - IDLE AIR CONTROL MOTOR 3 - THROTTLE POSITION SENSOR 4 - THROTTLE BODY
INSTALLATION
3.7L V-6
The Throttle Position Sensor (TPS) is mounted to
the throttle body (Fig. 56).
The throttle shaft end of throttle body slides into a socket in TPS (Fig. 61). 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 N·m (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.
4.7L V-8
The throttle shaft end of throttle body slides into a socket in TPS (Fig. 62). 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 N·m (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.
DR THROTTLE POSITION SENSOR (Continued)
FUEL INJECTION - GAS
14 - 55
5.9L V-8
The throttle shaft end of the throttle body slides into a socket in the TPS (Fig. 63). 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 N·m (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 intake tube.
Fig.61TPSINSTALLATION-3.7L
1 - THROTTLE BODY 2 - TPS 3 - THROTTLE BODY SHAFT 4 - SOCKET LOCATING TANGS
(5) Install air duct/air box to throttle body.
Fig.63TPSINSTALLATION-5.9LV-8AND8.0LV-10
1 - THROTTLE BODY 2 - THROTTLE POSITION SENSOR 3 - THROTTLE SHAFT 4 - SOCKET LOCATING TANGS8.0L V-10
The throttle shaft end of the throttle body slides into a socket in the TPS (Fig. 63). 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. Refer to
Torque Specifications.
(2) Manually operate throttle control lever by hand
to check for any binding of TPS.
(3) Connect TPS electrical connector to TPS. (4) Install air plenum.
Fig.62TPSINSTALLATION-4.7L
1 - THROTTLE BODY 2 - LOCATING TANGS 3 - THROTTLE POSITION SENSOR 4 - SOCKET 5 - THROTTLE SHAFT
14 - 56
FUEL DELIVERY - DIESEL
FUEL DELIVERY - DIESEL
TABLE OF CONTENTS
page
DR
page
FUEL DELIVERY - DIESEL
FUEL LINES
DESCRIPTION - DIESEL FUEL SYSTEM . . . . . 57
STANDARD PROCEDURESTANDARD PROCEDURES - WATER
DRAINING AT FUEL FILTER . . . . . . . . . . . . . . 57
STANDARD PROCEDURES - CLEANING
FUEL SYSTEM PARTS . . . . . . . . . . . . . . . . . 58
STANDARD PROCEDURE - FUEL SYSTEM
PRIMING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
SPECIFICATIONS
FUEL SYSTEM PRESSURE - DIESEL FUEL INJECTOR FIRING ORDER - DIESEL
. . . . . . 60
. 60SPECIAL TOOLS
DIESEL FUEL SYSTEM . . . . . . . . . . . . . . . . . 60
FUEL FILTER / WATER SEPARATOR
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 61
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 62FUEL HEATER
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 63
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
DIAGNOSIS AND TESTING - FUEL HEATER . . . 63
REMOVALREMOVAL/INSTALLATION . . . . . . . . . . . . . . . 64
FUEL HEATER RELAY
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 64
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 64FUEL INJECTION PUMP
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 64
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
DIAGNOSIS AND TESTING - FUEL INJECTIONPUMP TIMING . . . . . . . . . . . . . . . . . . . . . . . . 65
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 67FUEL LEVEL SENDING UNIT / SENSOR
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 68
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
REMOVALREMOVAL/INSTALLATION . . . . . . . . . . . . . . . 68
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 69
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
DIAGNOSIS AND TESTING - HIGH-PRESSURE FUEL LINE LEAKS . . . . . . . . . . . 69
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 71FUEL PRESSURE SENSOR
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 72
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 72FUEL PRESSURE LIMITING VALVE
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 72
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 73FUEL TANK
DESCRIPTION - DIESEL . . . . . . . . . . . . . . . . . . 73
. . . . . . . . . . . . . . . . . . . . . 73
REMOVAL - DIESEL INSTALLATION - DIESEL . . . . . . . . . . . . . . . . . 74FUEL TANK MODULE
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 75
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 75FUEL TRANSFER PUMP
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 75
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 76CASCADE OVERFLOW VALVE
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 77
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
REMOVALREMOVAL/INSTALLATION . . . . . . . . . . . . . . . 77
WATER IN FUEL SENSOR
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 77
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78FUEL DRAIN CIRCUIT
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
DR
FUEL DELIVERY - DIESEL
14 - 57
FUEL DELIVERY - DIESEL DESCRIPTION - DIESEL FUEL SYSTEM
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 † Fuel Pump/Gear Pump (attached to fuel injec- tion 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 † Fuel Drain Manifold (passage) † Fuel Drain Valve (at filter) † Fuel Filter/Water Separator † Fuel Heater † Fuel Heater Relay † Fuel Level (gauge) Sending Unit † Fuel Tank † Fuel Tank Module (containing fuel gauge send- ing unit and separate fuel filter located at bottom of tank module)
† 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 mod- ule)† Low-Pressure Fuel Supply Lines † Low-Pressure Fuel Return Line † Overflow Valve † Quick-Connect Fuel Line Fittings † Throttle Cable † Water Draining (maintenance) † Water-In-Fuel (WIF) Sensor The fuel injection pump supplies high pressure to the fuel rail independent of engine speed. This high pressure 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 actu- ating the injectors.
Fuel enters the system from the electric fuel trans- fer (lift) pump, which is attached to the fuel filter assembly. Fuel is forced through the fuel filter ele- ment 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 sup- plied 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 open- ing and closing the FCA based on a demanded fuel pressure. The FPS (Fuel Pressure Sensor) on the fuel rail provides the actual fuel pressure. 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 by three radial pumping chambers. The pressurized fuel is then supplied to the fuel rail.
Some fuel system components are shown in.
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.Certain fuel system components can be found in
(Fig. 1), or (Fig. 2).
STANDARD PROCEDURE
STANDARD PROCEDURES - WATER DRAINING AT FUEL FILTER
Refer to Fuel Filter/Water Separator removal/in-
stallation for procedures.
FUEL DELIVERY - DIESEL
14 - 58
FUEL DELIVERY - DIESEL (Continued)DR
Fig.1DIESELFUELSYSTEMCOMPONENTS
1 - ENGINE COOLANT TEMPERATURE (ECT) SENSOR 2 - THROTTLE LEVER BELLCRANK AND APPS (ACCELERATOR PEDAL POSITION SENSOR) 3 - INTAKE MANIFOLD AIR HEATER/ELEMENTS 4 - FUEL PRESSURE SENSOR 5 - FUEL LIMITING VALVE 6 - HIGH-PRESSURE FUEL LINES 7 - FUEL HEATER 8 - HIGH-PRESSURE FUEL INJECTOR RAIL 9 - FUEL HEATER TEMPERATURE SENSOR (THERMOSTAT) 10 - FUEL FILTER/WATER SEPARATOR 11 - FUEL TRANSFER (LIFT) PUMP 12 - FUEL DRAIN MANIFOLD 13 - DRAIN VALVE
STANDARD PROCEDURES - CLEANING FUEL SYSTEM PARTS
CAUTION: Cleanliness cannot be overemphasized when handling or replacing diesel fuel system com- ponents. This especially includes the fuel injectors, high-pressure 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.
lines and fuel
14 - FUEL SUPPLY LINE (LOW-PRESSURE, TO ENGINE) 15 - FUEL RETURN LINE CONNECTION (TO FUEL TANK)
16 - FUEL DRAIN TUBE 17 - OIL PRESSURE SENSOR 18 - ENGINE CONTROL MODULE (ECM) 19 - FUEL INJECTION PUMP 20 - CRANKSHAFT POSITION (ENGINE SPEED) SENSOR 21 - CAMSHAFT POSITION SENSOR (CMP) 22 - FUEL CONTROL ACTUATOR (FCA) 23 - CASCADE OVERFLOW VALVE
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.
DR FUEL DELIVERY - DIESEL (Continued)
FUEL DELIVERY - DIESEL
14 - 59
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 on and 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) If the engine does not start after 25 seconds, turn key OFF. 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.
Fig.2FUELINJECTORS
1 - SOLENOID CONNECTIONS 2 - ROCKER HOUSING 3 - FUEL INJECTOR 4 - PASSTHROUGH CONNECTOR
STANDARD PROCEDURE - FUEL SYSTEM PRIMING
A certain amount of air becomes trapped in 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 usu-
ally will not require fuel system priming.
The fuel transfer (lift) pump is self-priming: When the key is first turned on (without cranking engine), the pump operates for approximately 2 seconds and then shuts off. The pump will also operate for up to
(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.
WARNING: THE FUEL INJECTION PUMP SUPPLIES EXTREMELY HIGH FUEL PRESSURE TO EACH INDI- VIDUAL INJECTOR THROUGH THE HIGH-PRES- SURE LINES. FUEL UNDER THIS AMOUNT OF PRESSURE CAN PENETRATE THE SKIN AND CAUSE PERSONAL INJURY. WEAR SAFETY GOG- GLES AND ADEQUATE PROTECTIVE CLOTHING. DO NOT LOOSEN FUEL FITTINGS WHILE ENGINE IS RUNNING.
WARNING: ENGINE MAY START WHILE CRANKING STARTER MOTOR.
FUEL DELIVERY - DIESEL
14 - 60
FUEL DELIVERY - DIESEL (Continued) SPECIFICATIONSFUEL SYSTEM PRESSURE - DIESEL
DR
DESCRIPTION
Fuel Transfer (Lift) Pump Pressure
PRESSURE
Minimum 9.5 psi
FUEL INJECTOR FIRING ORDER - DIESEL
1–5–3–6–2–4
SPECIAL TOOLS
DIESEL FUEL SYSTEM
FUELPRESSURETESTADAPTER-#9012
FUELPRESSURETESTADAPTER-#9014
FUELINJECTORREMOVER-#9010
PRESSURECAP-#9011
FUELPRESSURETESTADAPTER-#9013
DR FUEL DELIVERY - DIESEL (Continued)
FUEL DELIVERY - DIESEL
14 - 61
A Water-In-Fuel (WIF) sensor is attached to side of canister. Refer to Water-In-Fuel Sensor Description/ Operation.
The fuel heater is installed into the top of the fil- ter/separator housing. Refer to Fuel Heater Descrip- tion/Operation.
REMOVAL
FUELINJECTORTUBE(CONNECTOR)REMOVER-
#9015
SPANNERWRENCH(FUELTANKMODULE
REMOVAL/INSTALLATION)-#6856
ENGINEROTATING(BARRING)TOOL-#7471B
(ALSOPARTOFKIT#6860)
FUEL FILTER / WATER SEPARATOR DESCRIPTION
The fuel filter/water separator assembly is located on left side of engine above starter motor. The assem- bly also includes the fuel heater and Water-In-Fuel (WIF) sensor, and fuel transfer pump.
OPERATION
The fuel
filter/water separator protects the fuel injection pump by removing water and contaminants from the fuel. The construction of the filter/separator allows fuel to pass through it, but helps prevent moisture (water) from doing so. Moisture collects at the bottom of the canister.
Refer to the maintenance schedules for the recom-
mended fuel filter replacement intervals.
For draining of water from canister, refer to Fuel Filter/Water Separator Removal/Installation section.
Refer to maintenance schedules in this manual for
recommended fuel filter replacement intervals.
Draining water from fuel filter/water separa-
tor housing:
The housing drain valve (Fig. 3) or (Fig. 4) serves two purposes. One is to partially drain filter hous- ing of excess water. The other is to completely drain housing for fuel filter, drain valve, heater element, , water-in-fuel sensor replacement or transfer pump replacement.
The filter housing should be partially drained whenever water-in-fuel warning lamp remains illumi- nated. lamp will be illuminated for approximately two seconds when ignition key is ini- tially placed in ON position for a bulb check).
(Note that
(1) A drain hose (Fig. 3) or (Fig. 4) is located at bottom of drain valve. Place drain pan under drain. (2) With engine not running, rotate drain valve handle rearward to OPEN (DRAIN) position. Hold drain valve open until all water and contaminants have been removed and clean fuel exits.
(3) If drain valve, fuel heater element or Water-In- Fuel (WIF) sensor is being replaced, drain housing completely. Dispose of mixture in drain pan according to applicable regulations.
(4) After draining operation, push valve handle
forward to CLOSE position.
(5) Fuel Filter Replacement: The fuel filter is
located inside of the fuel filter housing.
(a) Clean all debris from around canister. (b) Remove filter lid (Fig. 5) using a socket. Attach socket to large hex on top of lid (Fig. 5). Rotate removal. Remove o-ring.
counter-clockwise
for
(c) Remove filter element by twisting element
sideways from filter lid. (6) Water-In-Fuel (WIF) Sensor Replacement: The WIF sensor is located on the side of the fuel fil- ter housing (Fig. 3) or (Fig. 4).
(a) Disconnect electrical connector at sensor. (b) Clean area around sensor. (c) Remove sensor by rotating counter-clockwise. (d) Check condition of sensor o-ring. Replace if
damaged. (7) Fuel Heater Element Replacement: The heater element is located in the fuel filter housing (Fig. 3) or (Fig. 4).
(a) Remove fuel filter. See previous steps.
FUEL DELIVERY - DIESEL
14 - 62
FUEL FILTER / WATER SEPARATOR (Continued)DR
(b) Disconnect electrical connector. (c) Remove two T-15 Torx head mounting screws
from fuel heater element.
(d) Remove fuel filter cover and filter element. (e) Remove fuel heater.
(8) Drain Valve Replacement: The drain valve assembly is located on the side of the fuel filter hous- ing (Fig. 3) or (Fig. 4).
(a) Disconnect drain hose from the fuel drain
valve.
Torx head).
(b) Remove 4 drain valve mounting screws (T-15
(c) Remove drain valve from filter housing.
Fig.4FILTERHOUSING(LATE)
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
Fig.5FILTERCOVER(LID)
1 - FILTER COVER 2 - ATTACH SOCKET HERE
Fig.3FILTERHOUSING(EARLY)
1 - FILTER HOUSING 2 - FUEL HEATER AND THERMOSTAT 3 - FUEL HEATER MOUNTING SCREWS 4 - FUEL HEATER ELEC. CONNECTOR 5 - DRAIN VALVE 6 - DRAIN VALVE MOUNTING SCREWS 7 - DRAIN HOSE 8 - WIF SENSOR 9 - WIF SENSOR ELEC. CONNECTOR
INSTALLATION
Refer to maintenance schedules for recommended
fuel filter replacement intervals.
(1) Thoroughly clean inside of filter housing, filter
cap and all related components.
(2) Fuel Filter:
(a) The engine has a self-priming low-pres- sure fuel system. Refer to Standard Proce- dures-Fuel System Priming.
(b) Install new o-ring to canister lid and lubri-
cate o-ring with 30W oil.
DR FUEL FILTER / WATER SEPARATOR (Continued)
FUEL DELIVERY - DIESEL
14 - 63
(c) Position new element to canister lid. Place
this assembly into canister by rotating clockwise.
(d) Tighten cap to 34 N·m (25 ft. lbs.) torque. Do
not overtighten cap. (3) Water-In-Fuel (WIF) Sensor:
(a) Install new o-ring seal to WIF sensor. (b) Apply a light film of clean diesel oil to o-ring
seal.
(c) Install sensor into housing. (d) Tighten sensor to 4.5 N·m (39 in. lbs.) torque. (e) Connect electrical connector to WIF sensor.
(4) Fuel Heater Element:
(a) Install fuel heater into fuel filter housing. (b) Install fuel heater thermostat into fuel filter
housing.
thermostat.
(c) Install
fuel heater mounting screws and
tighten to 1-1.5 N·m torque.
(d) Connect electrical connector to fuel heater
(e) Install new filter cover O-ring onto fuel filter
housing cover and lubricate with 30W oil.
(f) Tighten fuel filter housing cover (lid) to 34
N·m (25 ft. lbs.). (5) Drain Valve:
ing.
(a) Install 2 new o-rings to valve and filter hous-
(b) Lubricate with silicon grease. (c) Install fuel drain valve. (d) Install 4 mounting screws and tighten to
1–1.5 N·m (8–13 in. lbs.) torque.
(e) Connect drain hose to drain valve.
(6) Start engine and check for leaks.
FUEL HEATER DESCRIPTION
The fuel heater assembly is located on the side of
the fuel filter housing (Fig. 3) or (Fig. 4).
The heater/element assembly is equipped with a temperature sensor (thermostat) that senses fuel temperature. This sensor is attached to the fuel heat- er/element assembly.
OPERATION
The fuel heater is used to prevent diesel fuel from
waxing during cold weather operation.
When the temperature is below 45 ±8 degrees F, the temperature sensor allows current to flow to the heater element warming the fuel. When the temper- ature is above 75 ±8 degrees F, the sensor stops cur- rent flow to the heater element.
Battery voltage to operate the fuel heater element is supplied from the ignition switch and through the fuel heater relay. Also refer to Fuel Heater Relay.
The fuel heater element and fuel heater relay are not computer controlled.
The heater element operates on 12 volts, 300 watts
at 0 degrees F.
DIAGNOSIS AND TESTING - FUEL HEATER
The fuel heater is used to prevent diesel fuel from
waxing during cold weather operation.
NOTE: The fuel heater element, fuel heater relay and fuel heater temperature sensor are not con- trolled by the Engine Control Module (ECM), or the Powertrain Control Module (PCM).
A malfunctioning fuel heater can cause a wax build-up in the fuel filter/water separator. Wax build-up in the filter/separator can cause engine starting problems and prevent the engine from rev- ving up. It can also cause blue or white fog-like exhaust. If the heater is not operating in cold tem- peratures, the engine may not operate due to fuel waxing.
The fuel heater assembly is located on the side of
fuel filter housing.
The heater assembly is equipped with a built-in fuel temperature sensor (thermostat) that senses fuel temperature. When fuel temperature drops below 45
degrees ± 8 degrees F, the sensor allows current to flow to built-in heater element to warm fuel. When fuel temperature rises above 75 degrees ± 8 degrees F, the sensor stops current flow to heater element (circuit is open).Voltage to operate fuel heater element is supplied from ignition switch, through fuel heater relay (also refer to Fuel Heater Relay), to fuel temperature sen- sor and on to fuel heater element.
The heater element operates on 12 volts, 300 watts at 0 degrees F. As temperature increases, power requirements decrease.
A minimum of 7 volts is required to operate fuel heater. The resistance value of heater element is less than 1 ohm (cold) and up to 1000 ohms warm.
TESTING
(Fig. 3) or (Fig. 4).
(1) Disconnect electrical connector from thermostat
Ambient temperature must be below circuit close temperature, If necessary, induce this ambient tem- perature by placing ice packs on thermostat to pro- duce an effective ambient temperature below circuit close temperature. For first check of thermostat you can hear click of thermostat when circuit closes.
Measure resistance across two pins. Operating
range is 0.3 — 0.45 Ohms.
(2) If resistance is out of range, remove thermostat and check resistance across terminal connections of
FUEL DELIVERY - DIESEL
14 - 64
FUEL HEATER (Continued)heater. The heater can be check at room tempera- ture. Operating range is 0.3 — 0.45 Ohms.
(3) Replace heater if resistance is not within oper-
ating range.
heater thermostat.
(4) If heater is within operating range, replace
REMOVAL
REMOVAL/INSTALLATION
The fuel heater/element/sensor assembly is located inside of the fuel filter housing. Refer to Fuel Filter/ Water Separator Removal/Installation for procedures.
FUEL HEATER RELAY DESCRIPTION
The fuel heater relay is located in Power Distribu- tion Center (PDC) (Fig. 6). Refer to label on inside of PDC cover for relay location.
Fig.6POWERDISTRIBUTIONCENTERLOCATION 1 - CLIP 2 - BATTERY 3 - TRAY 4 - NEGATIVE CABLE 5 - POSITIVE CABLE 6 - CLIP 7 - FENDER INNER SHIELD 8 - POWER DISTRIBUTION CENTER
OPERATION
Battery voltage to operate the fuel heater element is supplied from the ignition switch through the fuel heater relay. The fuel heater element and fuel heater relay are not computer controlled.
REMOVAL
The fuel heater relay is located in the Power Dis- tribution Center (PDC) (Fig. 7). Refer to label under PDC cover for relay location.
(1) Remove PDC cover. (2) Remove relay from PDC.
DR
(3) Check condition of relay terminals and PDC connector terminals for damage or corrosion. Repair if necessary before installing relay.
(4) Check for pin height (pin height should be the same for all terminals within the PDC connector). Repair if necessary before installing relay.
Fig.7POWERDISTRIBUTIONCENTERLOCATION 1 - CLIP 2 - BATTERY 3 - TRAY 4 - NEGATIVE CABLE 5 - POSITIVE CABLE 6 - CLIP 7 - FENDER INNER SHIELD 8 - POWER DISTRIBUTION CENTER
INSTALLATION
The fuel heater relay is located in the Power Dis- tribution Center (PDC) (Fig. 7). Refer to label under PDC cover for relay location.
(1) Install relay to PDC. (2) Install cover to PDC.
FUEL INJECTION PUMP DESCRIPTION
A Robert Bosch high-pressure fuel injection pump is used. The pump is attached to the back of the tim- ing gear cover at the left / rear side of the engine.
OPERATION
The fuel injection pump supplies high pressure to the fuel rail independent of engine speed. This high pressure 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 actu- ating the injectors.
Fuel enters the system from the electric fuel trans- fer (lift) pump, which is attached to the fuel filter assembly. Fuel is forced through the fuel filter ele- ment and then enters the Fuel Pump/Gear Pump, which is attached to the rear of the fuel injection
DR FUEL INJECTION PUMP (Continued)
FUEL DELIVERY - DIESEL
14 - 65
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 sup- plied to the FAC (Fuel Control Actuator).
The FAC is an electronically controlled solenoid valve. The ECM controls the amount of fuel that enters the high-pressure pumping chambers by open- ing and closing the FAC based on a demanded fuel pressure. The FPS (Fuel Pressure Sensor) on the fuel rail provides the actual fuel pressure. 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 by three radial pumping chambers. The pressurized fuel is then supplied to the fuel rail.
DIAGNOSIS AND TESTING - FUEL INJECTION PUMP TIMING
With the Bosch injection pump,
there are no mechanical adjustments needed or necessary to accomplish fuel injection timing. All timing and fuel adjustments are electrically made by the engine mounted Engine Control Module (ECM).
REMOVAL
lines and fuel
CAUTION: Cleanliness cannot be overemphasized when handling or replacing diesel fuel system com- ponents. This especially includes the fuel injectors, high-pressure 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. Cover and isolate ends of both cables.
(2) Remove intake manifold air intake tube (above injection pump) and its rubber connector hose (Fig. 8).
(3) The Engine Control Module (ECM) is mounted to left side of engine (Fig. 9). Remove 5 ECM mount-
ing bolts and position ECM for injection pump removal. Do not disconnect wiring connectors from ECM.
(4) Remove cooling fan shroud. (5) Remove cooling fan assembly. (6) Remove accessory drive belt. (7) Thoroughly clean the rear of injection pump, and attachment points for its 3 fuel lines (Fig. 10). Also clean the opposite ends of these same 3 lines at their attachment points.
(8) Disconnect Fuel Control Actuator (FCA) electri-
cal connector at rear of injection pump (Fig. 11).
(9) Remove fuel
line (injection pump-to-overflow
valve).
housing).
(10) Remove fuel line (injection pump-to-fuel rail). (11) Remove fuel line (injection pump-to-fuel filter
(12) Remove fuel pump drive gear access cover (plate) with a 1/2 inch drive ratchet. Plate is threaded to timing gear cover (Fig. 12).
(13) Remove fuel pump drive gear mounting nut
and washer.
(14) Attach C3428B, or L4407A (or equivalent) gear puller (Fig. 13) to pump drive gear with 2 bolts, and separate gear from pump (a keyway is not used on this particular injection pump). Leave drive gear hanging loose within timing gear cover.
(15) Remove 3 injection pump mounting nuts (Fig.
14), and remove pump from engine.
Fig.8INTAKETUBEANDCONNECTINGHOSE
1 - MANIFOLD ABOVE HEATERS 2 - RUBBER CONNECTING HOSE 3 - METAL INTAKE TUBE 4 - CLAMPS (2)
FUEL DELIVERY - DIESEL
14 - 66
FUEL INJECTION PUMP (Continued)DR
Fig.9ECMREMOVAL/INSTALLATION
Fig.11FUELCONTROLACTUATOR
1 - ECM LOCATION 2 - ELECTRICAL CONNECTORS (2) 3 - CONNECTOR BOLTS 4 - ECM MOUNTING BOLTS (5) 5 - BOTTOM OF INJECTION PUMP
1 - ACTUATOR MOUNTING BOLTS 2 - FCA (FUEL CONTROL ACTUATOR) 3 - ACTUATOR ELECTRICAL CONNECTOR
Fig.10OVERFLOWVALVE
1 - BANJO BOLTS 2 - PUMP MOUNTING NUTS (3) 3 - FUEL INJECTION PUMP 4 - CASCADE OVERFLOW VALVE
Fig.12PUMPDRIVEGEARACCESSCOVER
1 - FRONT TIMING GEAR COVER 2 - GEAR ACCESS PLATE (COVER) 3 - HEX DRIVE (FOR COVER REMOVAL/INSTALLATION)
DR FUEL INJECTION PUMP (Continued)
FUEL DELIVERY - DIESEL
14 - 67
INSTALLATION
lines and fuel
CAUTION: Cleanliness cannot be overemphasized when handling or replacing diesel fuel system com- ponents. This especially includes the fuel injectors, high-pressure 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.
Fig.13DRIVEGEARREMOVAL
1 - FRONT TIMING GEAR COVER 2 - GEAR PULLER TOOL
(1) Inspect pump mounting surfaces at pump and mounting flange for nicks, cuts or damage. Inspect o-ring surfaces for nicks, cuts or damage.
(2) Clean injection pump mounting flange at gear
housing. Also clean front of injection pump.
(3) Install new rubber o-ring into machined groove
(Fig. 14) at pump mounting area.
1 - PUMP DRIVE GEAR NUT 2 - WASHER 3 - PUMP DRIVE GEAR 4 - RUBBER O-RING 5 - FUEL INJECTION PUMP
Fig.14FUELINJECTIONPUMPREMOVAL/INSTALLATION
6 - PUMP MOUNTING NUTS (3) 7 - PUMP MOUNTING STUDS (3) 8 - O-RING MACHINED GROOVE 9 - FRONT TIMING GEAR COVER
FUEL DELIVERY - DIESEL
14 - 68
FUEL INJECTION PUMP (Continued)(4) Apply clean engine oil to injection pump
o-ring only.
The machined tapers on both injection pump shaft and injection pump gear must be abso- lutely dry, clean and free of any dirt or oil film. This will ensure proper gear-to-shaft tighten- ing.
(5) Clean pump gear and pump shaft at machined tapers with an evaporative type cleaner such as brake cleaner.
(6) Position injection pump to mounting flange on cover while aligning injection pump shaft
gear through back of injection pump gear. (7) After pump is positioned flat
to mounting flange, install 3 pump mounting nuts and tighten finger tight only. Do not attempt a final tightening at this time. Do not attempt to tighten (pull) pump to gear cover using mounting nuts. Dam- age to pump or gear cover may occur. The pump must be positioned flat to its mounting flange before attempting to tighten 3 mounting nuts.
(8) To prevent damage or cracking of components,
install and tighten nuts in the following sequence:
(a) Install injection pump shaft washer and nut
to pump shaft. Tighten nut finger tight only.
(b) Do preliminary (light) tightening of injection
pump shaft nut.
N·m (70.8 in. lbs.).
(c) Tighten 3 injection pump mounting nuts to 8
(d) Do a final tightening of pump shaft nut to
105 N·m (77 ft. lbs.). (9) Install drive gear access cover (plate) using a 1/2 inch drive ratchet. Plate is threaded to timing gear cover.
(10) Install Engine Control Module (ECM) to left
side of engine. (11) Install
fuel
line (injection pump-to-overflow
valve). Tighten bolts to 24 N·m (17 ft. lbs.) torque.
(12) Install fuel line (injection pump-to-fuel rail).
Tighten to 24 N·m (17 ft. lbs.) torque.
(13) Install fuel line (injection pump-to-fuel filter
housing). Tighten to 24 N·m (17 ft. lbs.) torque.
(14) Connect Fuel Control Actuator (FCA) electri-
cal connector to rear of injection pump.
(15) Install intake manifold air intake tube (above
injection pump). Tighten clamps.
(16) Install accessory drive belt. (17) Install cooling fan shroud. (18) Install cooling fan assembly. (19) Connect both negative battery cables to both
batteries.
(20) Check system for fuel or engine oil leaks.
DR
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 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 ECM through the sensor return circuit.
level
Both of the electrical circuits between the fuel gauge sending unit and the ECM are hard-wired (not multi-plexed). After the voltage signal is sent from the resistor track, and back to the ECM, the ECM 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.
REMOVAL
REMOVAL/INSTALLATION
For diesel removal and installation procedures, refer to the gas section of Fuel System/Fuel Delivery. See Fuel Level Sending Unit/Sensor Removal/Instal- lation.
DR
FUEL LINES DESCRIPTION
Low-Pressure Lines † the fuel supply line from fuel tank to fuel trans- fer (lift) pump. † the fuel return line back to fuel tank. † the fuel drain manifold line at rear of cylinder head.† the fuel supply line from fuel filter to fuel injec- tion pump.
High-Pressure Lines † the fuel line from fuel injection pump to overflow valve.† the fuel line from fuel injection pump to fuel rail.† the 6 fuel lines from fuel rail up to injector con- nector tubes
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.OPERATION
High-Pressure 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. 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.
If
High-pressure fuel lines deliver fuel (under pres- sure) of up to approximately 160,000 kPa (23,206
PSI) from the injection pump to the fuel injectors. The lines expand and contract from the high-pres- sure fuel pulses generated during the injection pro- cess. 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.FUEL DELIVERY - DIESEL
14 - 69
EXTREME CAUTION WHEN WARNING: USE 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 160,000 kPa (23,206 PSI), USE EXTREME CAUTION WHEN INSPECTING FOR HIGH-PRES- SURE FUEL LEAKS. DO NOT GET YOUR HAND OR A FINGER NEAR A SUSPECTED LEAK. INSPECT FOR HIGH-PRESSURE FUEL LEAKS WITH A SHEET OF CARDBOARD. HIGH FUEL INJECTION PRES- SURE CAN CAUSE PERSONAL INJURY IF CON- TACT IS MADE WITH THE SKIN.
Start the engine. Move the cardboard (Fig. 15) over the suspected high-pressure fuel line leak, and check for fuel spray onto the cardboard. If line is leaking, retorque line. Replace damaged, restricted or leaking high-pressure fuel lines with the correct replacement line.
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
lines and fuel
CAUTION: Cleanliness cannot be overemphasized when handling or replacing diesel fuel system com- ponents. This especially includes the fuel injectors, high-pressure 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.
FUEL DELIVERY - DIESEL
14 - 70
FUEL LINES (Continued)DR
(7) Carefully remove each fuel line from engine. Note position of each while removing. Do not bend lines while removing.
Fig.16BRACKET-#6INJECTOR
1 - BRACKET 2 - REAR OF CYLINDER HEAD 3 - FUEL DRAIN MANIFOLD LINE (TO FUEL TANK) 4 - BANJO BOLT 5 - SLOTTED HOLE 6 - BRACKET BOLTS (2)
Fig.15TYPICALTESTFORLEAKSUSING
CARDBOARD
1 - HIGH-PRESSURE LINE 2 - CARDBOARD 3 - TYPICAL HIGH-PRESSURE FITTING
(1) Disconnect both negative battery cables from
both batteries. Cover and isolate ends of cables.
(2) Thoroughly clean fuel lines at both the cylinder
head and injection pump ends.
(3) If removing fuel line at either #1 or #2 cylinder, the intake manifold air heater elements must first be removed from top of intake manifold. Refer to Intake Air Heater Removal / Installation for procedures.
(4) If removing fuel line at #6 cylinder, a bracket (Fig. 16) is located above fuel line connection at cyl- inder head. Two bolts secure this bracket to rear of cylinder head. The upper bolt hole is slotted. Loosen (but do not remove) these 2 bracket bolts. Tilt bracket down to gain access to #6 fuel line connec- tion.
(5) Remove necessary insulated fuel line support clamps (Fig. 17) and bracket bolts at intake manifold. (6) Place shop towels around fuel lines at fuel rail and injectors. If possible, do not allow fuel to drip down side of engine.
CAUTION: WHEN LOOSENING OR TIGHTENING HIGH-PRESSURE LINES ATTACHED TO A SEPA- RATE FITTING (Fig. 18) , USE A BACK-UP WRENCH ON FITTING. DO NOT ALLOW FITTING TO ROTATE. DAMAGE TO BOTH FUEL LINE AND FITTING WILL RESULT.
Fig.17FUELINJECTORRAIL
1 - FUEL RAIL MOUNTING BOLTS (3) 2 - INSULATED CLAMPS 3 - FUEL INJECTOR RAIL
DR FUEL LINES (Continued)
FUEL DELIVERY - DIESEL
14 - 71
Fig.18HIGHPRESSUREFUELLINES
5 - SEPARATE FITTING (TYPICAL) 6 - CONNECTOR TUBE RETAINER (FITTING) 7 - CONNECTOR TUBE
1 - FUEL INJECTOR 2 - HIGH-PRESSURE LINE 3 - INJECTOR MOUNTING BOLTS 4 - FUEL INJECTOR RAIL
INSTALLATION
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.
(1) Position fuel line support clamp to fuel line.
Install clamp nuts/bolts and tighten finger tight.
(2) Position proper fuel line to proper injector on engine. Tighten fittings hand tight at both ends of line.
(3) Tighten fuel lines at high pressure injector con-
nector to 30 N·m (22 lb. ft.).
(4) Tighten fuel lines at fuel rail to 30 N·m (22 lb.
ft.).
(5) Tighten clamp/support nuts and bolts. (6) Install engine lifting bracket and bolt. Tighten
bolt to 77 N·m (56 lb.ft.).
(7) If fuel line at either #1 or #2 cylinder has been replaced, install intake manifold air heater elements to top of intake manifold. Refer to Intake Air Heater Removal / Installation for procedures.
(8) If fuel line at #6 cylinder has been replaced, tilt metal bracket upward and tighten 2 bolts at rear of cylinder head.
(9) Install remaining fuel line support clamps and
bracket bolts at intake manifold.
(10) Connect both negative battery cables to both
(11) Prime fuel system. Refer to Fuel System
batteries.
Priming.
(12) Check lines/fittings for leaks.
14 - 72
FUEL DELIVERY - DIESEL
DR
FUEL PRESSURE SENSOR DESCRIPTION
The fuel pressure sensor is mounted vertically near
the top/center of the fuel rail.
OPERATION
The fuel pressure sensor monitors actual high- pressure within the fuel rail. An output signal from this sensor (relating to fuel pressure) is sent to the Engine Control Module (ECM).
REMOVAL
The fuel pressure sensor is mounted vertically near
the top/center of the fuel rail (Fig. 19).
(1) Disconnect electrical connector at sensor. (2) Remove sensor from fuel rail. (3) Inspect sensor o-ring.
Fig.19FUELPRESSURESENSOR/FUELPRES.
LIMIT.VALVE
1 - ELEC. CONNECTOR 2 - BANJO BOLT 3 - FUEL PRESSURE LIMITING VALVE 4 - FUEL PRESSURE SENSOR 5 - TOP OF INTAKE HEATER MANIFOLD
INSTALLATION
(1) Inspect fuel pressure sensor o-ring. (2) Lubricate sensor o-ring with clean diesel fuel. (3) Install sensor into fuel rail. (4) To prevent leaks, sensor must be tightened to prescribed torque. Tighten sensor to 101 N·m (75 ft. lbs.) torque.
(5) Connect electrical connector to sensor. (6) Start engine and check for fuel leaks.
FUEL PRESSURE LIMITING VALVE DESCRIPTION
The fuel pressure limiting valve is located on the
top of the fuel rail.
OPERATION
Fuel pressure at the fuel rail is monitered by the fuel rail pressure sensor. If fuel pressure becomes excessive, the pressure limiting valve opens and vents excess pressure into the fuel drain circuit.
REMOVAL
The fuel pressure limiting valve is located on the
top of the fuel rail (Fig. 20).
lines and fuel
CAUTION: Cleanliness cannot be overemphasized when handling or replacing diesel fuel system com- ponents. This especially includes the fuel injectors, high-pressure 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) Thoroughly clean area at pressure limiting
(2) Remove banjo bolt (Fig. 20) at banjo fitting. (3) Remove pressure limiting valve from intake
valve.
manifold.
DR FUEL PRESSURE LIMITING VALVE (Continued)
FUEL DELIVERY - DIESEL
14 - 73
(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) Remove rubber cap from auxiliary fitting on
top of tank module (Fig. 21).
(5) Drain fuel tank by attaching drain hose from an approved draining station to auxiliary fitting on top of tank module (Fig. 21).
Fig.20FUELPRESSURESENSOR/FUEL
PRESSURELIMITINGVALVE
1 - ELEC. CONNECTOR 2 - BANJO BOLT 3 - FUEL PRESSURE LIMITING VALVE 4 - FUEL PRESSURE SENSOR 5 - TOP OF INTAKE HEATER MANIFOLD
INSTALLATION
(1) Be sure both top of manifold and limiting valve
(2) Assemble banjo bolt and new sealing washers
(3) Tighten banjo bolt to 24 N·M (17 ft.
lbs.)
are clean.
to limiting valve.
torque.
FUEL TANK DESCRIPTION - DIESEL
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.
REMOVAL - DIESEL
Fuel Tank Draining
Due to a one-way check valve installed into the fuel fill opening fitting at the tank, the tank cannot be drained conventionally at the fill cap.
(1) Raise vehicle.
Fig.21FUELTANKMODULE-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
Tank Removal
(1) Loosen clamp and disconnect rubber fuel fill
hose at tank.
(2) Support tank with a hydraulic jack. (3) Remove 2 fuel tank strap nuts (Fig. 22) and
remove both tank support straps.
(4) Carefully lower tank a few inches and discon- nect fuel pump module electrical connector (Fig. 21) at top of tank. To disconnect electrical connector: Push upward on red colored tab to unlock. Push on black colored tab while removing connector.
(5) Disconnect fuel supply and return lines at fuel tank module (Fig. 21). Refer to Quick-Connect Fit- tings for procedures.
(6) Continue to lower tank for removal.
FUEL DELIVERY - DIESEL
14 - 74
FUEL TANK (Continued)(7) If fuel tank is to be replaced, remove fuel tank module from tank. Refer to Fuel Tank Module Removal/Installation procedures.
INSTALLATION - DIESEL
(1) If fuel tank is to be replaced, install fuel tank module into tank. Refer to Fuel Tank Module Remov- al/Installation procedures.
(2) Position fuel tank to hydraulic jack. (3) Raise tank until positioned near body. (4) Connect fuel tank module electrical connector
DR
(6) Continue raising tank until positioned snug to
body.
(7) Install and position both tank support straps. Install 2 fuel tank strap nuts and tighten. Tighten rear strap nut first. Refer to Torque Specifications.
(8) Remove hydraulic jack. (9) Connect rubber fill hose to fuel fill tube and
tighten clamp.
(10) Install tire / wheel (if necessary). (11) Lower vehicle. (12) Fill fuel tank with fuel. (13) Start engine and check for fuel leaks near top
at top of tank.
module.
(5) Connect fuel supply and return lines to tank
of module.
1 - FUEL TANK 2 - STRAP MOUNTING STUDS 3 - VEHICLE FRAME
Fig.22FUELTANKMOUNTING
4 - MOUNTING STRAPS 5 - STRAP NUTS
DR
FUEL DELIVERY - DIESEL
14 - 75
FUEL TANK MODULE DESCRIPTION
An electric fuel pump is not used in the fuel tank module for diesel powered engines. Fuel is supplied by the engine mounted fuel transfer (lift) pump.
The fuel tank module is installed in the top of the fuel tank (Fig. 23). The fuel tank module contains the following components: † Fuel reservoir † A separate in-tank fuel filter † Fuel gauge sending unit (fuel level sensor) † Fuel supply line connection † Fuel return line connection † Auxiliary non-pressurized fitting
locknut and remove locknut (Fig. 24). The fuel tank module will spring up when locknut is removed.
(4) Remove module from fuel tank.
Fig.24LOCKNUTREMOVAL/INSTALLATION-
TYPICALMODULE
1 - SPECIAL TOOL 6856
2 - LOCKNUTINSTALLATION
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.)
(6) Install fuel tank. Refer to Fuel Tank Removal/
torque.
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).
Fig.23FUELTANKMODULE-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
OPERATION
Refer to Fuel Gauge Sending Unit.
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
is threaded onto fuel tank. Install Special Tool 6856 to
tank module
locknut
fuel
FUEL DELIVERY - DIESEL
14 - 76
FUEL TRANSFER PUMP (Continued) OPERATIONDR
The purpose of the fuel transfer pump is to supply (transfer) a low-pressure fuel source: from the fuel tank, through the fuel filter/water separator and to the fuel injection pump. Here, the low-pressure is raised to a high-pressure by the fuel injection pump for operation of injectors. Check valves within the pump, control direction of fuel flow and prevent fuel bleed-back during engine shut down.
the high-pressure fuel
Maximum current flow to the pump is 5 amperes. With the engine running, the pump has a 100 per- cent duty-cycle with a minimum pressure of 11.5 psi. The transfer pump is self-priming: When the key is first turned on (without cranking engine), the pump will operate for approximately 1/2 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 injection pump requires. Excess fuel is returned from the injection pump through an overflow valve, and then back to the fuel tank.
than the fuel
REMOVAL
The fuel transfer pump (fuel lift pump) is attached to the rear of the fuel filter/water separator housing (Fig. 25).
(1) Drain fuel from fuel filter housing. Refer to Fuel Filter/Water Separator - Removal. See Draining. (2) Disconnect electrical connector (Fig. 25) from
fuel transfer pump.
fuel
(3) Disconnect
tank supply line from fuel transfer pump extension line. Do this at disconnec- tion point at inside of left inner frame rail (Fig. 26). Refer to quick-connect fittings for procedures. The fuel line extension is permanently attached to the transfer pump. Do not attempt to discon- nect fuel line at transfer pump.
(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.
Fig.25FUELTRANSFER(LIFT)PUMP
1 - FILTER HOUSING 2 - ELEC. CONNECTOR 3 - FUEL TRANSFER (LIFT) PUMP 4 - FUEL LINE EXTENTION 5 - MOUNTING BOLTS (4)
Fig.26TRANSFERPUMPFUELLINECONNECT
1 - LEFT INNER FRAME RAIL 2 - FUEL RETURN LINE 3 - FUEL SUPPLY LINE 4 - QUICK-CONNECT FITTING
DR FUEL TRANSFER PUMP (Continued)
(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 II Scan Tool to actuate transfer pump. Check for leaks.
(8) Operate engine and check for fuel leaks.
CASCADE OVERFLOW VALVE DESCRIPTION
The cascade overflow valve is located on the top/
rear side of the fuel injection pump (Fig. 27).
FUEL DELIVERY - DIESEL
14 - 77
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. 28), or (Fig. 29).
Fig.28FILTERHOUSING(EARLY)
1 - FILTER HOUSING 2 - FUEL HEATER AND THERMOSTAT 3 - FUEL HEATER MOUNTING SCREWS 4 - FUEL HEATER ELEC. CONNECTOR 5 - DRAIN VALVE 6 - DRAIN VALVE MOUNTING SCREWS 7 - DRAIN HOSE 8 - WIF SENSOR 9 - WIF SENSOR ELEC. CONNECTOR
Fig.27OVERFLOWVALVE
1 - BANJO BOLTS 2 - PUMP MOUNTING NUTS (3) 3 - FUEL INJECTION PUMP 4 - CASCADE OVERFLOW VALVE
OPERATION
When the fuel control actuator (FCA) is opened, the maximum amount of fuel is being delivered to the fuel injection pump. Any fuel that does not enter the injection pump is directed to the cascade overflow valve. 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.
FUEL DELIVERY - DIESEL
14 - 78
WATER IN FUEL SENSOR (Continued)DR
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 CIRCUIT OPERATION
incorporates
The Fuel Drain Circuit
several sources of fuel return. Fuel travels from the fuel tank to the fuel transfer pump and is forced through the fuel filter. A portion of that fuel travels through the fuel filter and into the fuel injection pump, while the rest of the fuel flows through a passage in the fuel filter housing. 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 and sent into a passage in the fuel pump. At this point the fuel is channeled into two passages. One passage sends fuel to the FCA (Fuel Control Actua- tor). The other passage sends fuel to the cascade overflow valve. The overflow 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. This fuel line is connected to the same fuel filter housing passage that the fuel transfer pump is con- nected to.
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. This line is connected to the fuel filter housing at the fuel pump drain.
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 in the rear of the cylinder head, an then into an external fuel line. This line is connected to the vehicles fuel return line, and returns excess fuel back to the fuel tank.
Fig.29FILTERHOUSING(LATE)
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
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.
DR
FUEL INJECTION - DIESEL
14 - 79
FUEL INJECTION - DIESEL
TABLE OF CONTENTS
page
page
ACCELERATOR PEDAL POSITION SENSOR
DESCRIPTION
DESCRIPTION (EARLY) DESCRIPTION (LATE)
. . . . . . . . . . . . . . . . 79
. . . . . . . . . . . . . . . . . . 79
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 82CAMSHAFT POSITION SENSOR
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 82
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 83CRANKSHAFT POSITION SENSOR
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 83
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 84FUEL CONTROL ACTUATOR
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 85
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 85FUEL INJECTOR
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 85
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 87FUEL INJECTOR RAIL
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 89
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 89ACCELERATOR PEDAL POSITION SENSOR
DESCRIPTION
DESCRIPTION (EARLY)
The APPS assembly is located at the top-left-front of the engine. A plastic cover is used to cover the assembly. The actual sensor is located behind its mounting bracket.
DESCRIPTION (LATE)
The Accelerator Pedal Position Sensor (APPS) assembly is located under the vehicle battery tray. A cable connects the assembly to the accelerator pedal.
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 90INLET AIR TEMPERATURE SENSOR/
PRESSURE SENSOR DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 90
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 90INTAKE AIR HEATER
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 91
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 91INTAKE AIR HEATER RELAY
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 92
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
