ignition DODGE RAM 2002 Service Repair Manual
[x] Cancel search | Manufacturer: DODGE, Model Year: 2002, Model line: RAM, Model: DODGE RAM 2002Pages: 2255, PDF Size: 62.07 MB
Page 1317 of 2255

(5) Push therightfuel rail down until fuel injec-
tors have bottomed on injector shoulder. Push the
leftfuel rail down until fuel injectors have bottomed
on injector shoulder.
(6) Install fuel rail mounting bolts.
(7) Connect electrical connector to intake manifold
air temperature sensor.
(8) Connect electrical connectors at all fuel injec-
tors. To install connector, refer to (Fig. 26). Push con-
nector onto injector (1) and then push and lock red
colored slider (2). Verify connector is locked to injec-
tor by lightly tugging on connector.
(9) Install the A/C support bracket (if equipped).
(10) Install throttle body to intake manifold. Refer
to Throttle Body installation in this section of the
group.
(11) Install fuel tube (line) at side of fuel rail.
Refer to Quick-Connect Fittings for procedures.
(12) Install air cleaner.
(13) Connect battery cable to battery.
(14) Start engine and check for leaks.
INSTALLATION - 8.0L
(1) Apply a small amount of engine oil to each fuel
injector o-ring. This will help in fuel rail installation.
(2) Install injector(s) and injector clip(s) to fuel
rail.
NOTE: The fuel injector electrical connectors on all
10 injectors should be facing to the right (passen-
ger) side of the vehicle (Fig. 31).
(3) Position the fuel rail/fuel injector assembly to
the injector openings on the intake manifold.
(4) Guide each injector into the intake manifold.
Be careful not to tear the injector o-ring.
(5) Push therightfuel rail down until fuel injec-
tors have bottomed on injector shoulder. Push the
leftfuel rail down until fuel injectors have bottomed
on injector shoulder.
(6) Install the six fuel rail mounting bolts into the
lower half of intake manifold. Tighten bolts to 15
N´m (136 in. lbs.) torque.
(7) Connect electrical connectors at all fuel injec-
tors. To install connector, refer to (Fig. 30). Push con-
nector onto injector (1) and then push and lock red
colored slider (2). Verify connector is locked to injec-
tor by lightly tugging on connector. The injector wir-
ing harness is numerically tagged.
(8) Install upper half of intake manifold. Refer to
Engines for procedures.
(9) Connect main fuel line at fuel rail. Refer to
Quick-Connect Fittings for procedures.
(10) Install ignition coil pack and bracket assem-
bly at intake manifold and right engine valve cover
(four bolts).(11) Install throttle body to intake manifold. Refer
to Throttle Body removal in this group.
(12) Install throttle body linkage to throttle body.
(13) Install air cleaner tube and housing.
(14) Install negative battery cable at battery.
(15) Start engine and check for leaks.
FUEL TANK
DESCRIPTION
The fuel tank is constructed of a plastic material.
Its main functions are for fuel storage and for place-
ment of the fuel pump module.
OPERATION
All models pass a full 360 degree rollover test
without fuel leakage. To accomplish this, fuel and
vapor flow controls are required for all fuel tank con-
nections.
A fuel tank check valve(s) is mounted into the top
of the fuel tank (or pump module). Refer to Emission
Control System for fuel tank check valve information.
An evaporation control system is connected to the
rollover valve(s) to reduce emissions of fuel vapors
into the atmosphere. When fuel evaporates from the
fuel tank, vapors pass through vent hoses or tubes to
a charcoal canister where they are temporarily held.
When the engine is running, the vapors are drawn
into the intake manifold. Certain models are also
equipped with a self-diagnosing system using a Leak
Detection Pump (LDP). Refer to Emission Control
System for additional information.
REMOVAL
WARNING: GASOLINE POWERED ENGINES: THE
FUEL SYSTEM IS UNDER A CONSTANT PRESSURE
EVEN WITH THE ENGINE OFF. BEFORE SERVICING
THE FUEL TANK, FUEL SYSTEM PRESSURE MUST
BE RELEASED. REFER TO THE FUEL SYSTEM
PRESSURE RELEASE PROCEDURE BEFORE SER-
VICING THE FUEL TANK.
Two different procedures may be used to drain fuel
tank (lowering tank or using DRB scan tool). When
equipped with a diesel engine, the DRB scan tool
cannot be used (no electric fuel pump).
The quickest draining procedure involves lowering
the fuel tank.
Gasoline Powered Engines:As an alternative
procedure, the electric fuel pump may be activated
allowing tank to be drained at fuel rail connection.
Refer to DRB scan tool for fuel pump activation pro-
cedures. Before disconnecting fuel line at fuel rail,
release fuel pressure. Refer to the Fuel System Pres-
sure Release Procedure in this group for procedures.
14 - 18 FUEL DELIVERY - GASOLINEBR/BE
FUEL RAIL (Continued)
Page 1328 of 2255

FUEL INJECTION - GASOLINE
DIAGNOSIS AND TESTING
VISUAL INSPECTIONÐ5.9L ENGINES
A visual inspection for loose, disconnected or incor-
rectly routed wires and hoses should be made. This
should be done before attempting to diagnose or ser-
vice the fuel injection system. A visual check will
help spot these faults and save unnecessary test and
diagnostic time. A thorough visual inspection will
include the following checks:
(1) Verify that the three 32±way electrical connec-
tors are fully inserted into the connector of the pow-
ertrain control module (PCM) (Fig. 1).
(2) Inspect the battery cable connections. Be sure
that they are clean and tight.
(3) Inspect fuel pump relay and air conditioning
compressor clutch relay (if equipped). Inspect the
ASD relay connections. Inspect starter motor relay
connections. Inspect relays for signs of physical dam-
age and corrosion. The relays are located in the
Power Distribution Center (PDC) (Fig. 2). Refer to
label on PDC cover for relay location.
(4) Inspect ignition coil connections. Verify that
coil secondary cable is firmly connected to coil (Fig.
3).
(5) Verify that distributor cap is correctly attached
to distributor. Be sure that spark plug cables are
firmly connected to the distributor cap and the spark
plugs are in their correct firing order. Be sure that
coil cable is firmly connected to distributor cap and
coil. Be sure that camshaft position sensor wire con-nector (at the distributor) is firmly connected to har-
ness connector. Inspect spark plug condition. Refer to
8, Ignition. Connect vehicle to an oscilloscope and
inspect spark events for fouled or damaged spark
plugs or cables.
(6) Verify that generator output wire, generator
connector and ground wire are firmly connected to
the generator.
(7) Inspect the system body grounds for loose or
dirty connections. Refer to 8, Wiring for ground loca-
tions.
(8) Verify positive crankcase ventilation (PCV)
valve operation. Refer to 25, Emission Control Sys-
tem for additional information. Verify PCV valve
hose is firmly connected to PCV valve and manifold
(Fig. 4).
Fig. 1 Powertrain Control Module (PCM)
1 - PCM MOUNTING BOLTS (3)
2 - POWERTRAIN CONTROL MODULE (PCM)
3 - (3) 32±WAY CONNECTORS
Fig. 2 Power Distribution Center (PDC)
1 - POWER DISTRIBUTION CENTER (PDC)
Fig. 3 Ignition CoilÐ5.9L EnginesÐTypical
1 - ACCESSORY DRIVE BELT TENSIONER
2 - COIL CONNECTOR
3 - IGNITION COIL
4 - COIL MOUNTING BOLTS
BR/BEFUEL INJECTION - GASOLINE 14 - 29
Page 1331 of 2255

(29) Inspect transmission torque convertor housing
(automatic transmission) or clutch housing (manual
transmission) for damage to timing ring on drive
plate/flywheel.
(30) Verify that battery cable and solenoid feed
wire connections to the starter solenoid are tight and
clean. Inspect for chaffed wires or wires rubbing up
against other components.
VISUAL INSPECTIONÐ8.0L ENGINE
A visual inspection for loose, disconnected or incor-
rectly routed wires and hoses should be made. This
should be done before attempting to diagnose or ser-
vice the fuel injection system. A visual check will
help spot these faults and save unnecessary test and
diagnostic time. A thorough visual inspection will
include the following checks:
(1) Verify that the three 32±way electrical connec-
tors are fully inserted into the connector of the pow-
ertrain control module (PCM) (Fig. 12).
(2) Inspect the battery cable connections. Be sure
that they are clean and tight.
(3) Inspect fuel pump relay and air conditioning
compressor clutch relay (if equipped). Inspect the
ASD relay connections. Inspect starter motor relay
connections. Inspect relays for signs of physical dam-
age and corrosion. The relays are located in the
Power Distribution Center (PDC) (Fig. 13). Refer to
label on PDC cover for relay location.
(4) Inspect ignition coil pack primary connections.
Verify that secondary cables are firmly connected to
coils (Fig. 14).
(5) Be sure that spark plug cables are firmly con-
nected and the spark plugs are in their correct firing
order. Be sure that camshaft position sensor wire
connector is firmly connected to harness connector.
Inspect spark plug condition. Refer to 8, Ignition.Connect vehicle to an oscilloscope and inspect spark
events for fouled or damaged spark plugs or cables.
(6) Verify that generator output wire, generator
connector and ground wire are firmly connected to
the generator.
(7) Inspect the system body grounds for loose or
dirty connections. Refer to 8, Wiring for ground loca-
tions.
(8) Verify crankcase ventilation (CCV) operation.
Refer to 25, Emission Control System for additional
information.
(9) Inspect fuel tube quick-connect fitting-to-fuel
rail connections.
(10) Verify that hose connections to all ports of
vacuum fittings on intake manifold are tight and not
leaking.
Fig. 11 Oxygen SensorsFig. 12 Powertrain Control Module (PCM)
1 - PCM MOUNTING BOLTS (3)
2 - POWERTRAIN CONTROL MODULE (PCM)
3 - (3) 32±WAY CONNECTORS
Fig. 13 Power Distribution Center (PDC)
1 - POWER DISTRIBUTION CENTER (PDC)
14 - 32 FUEL INJECTION - GASOLINEBR/BE
FUEL INJECTION - GASOLINE (Continued)
Page 1332 of 2255

(11) Inspect accelerator cable, transmission throt-
tle cable (if equipped) and cruise control cable con-
nections (if equipped). Check their connections to the
throttle arm of throttle body for any binding or
restrictions.
(12) If equipped with vacuum brake booster, verify
that vacuum booster hose is firmly connected to fit-
ting on intake manifold. Also check connection to
brake vacuum booster.
(13) Inspect the air cleaner inlet and air cleaner
element for dirt or restrictions.
(14) Inspect radiator grille area, radiator fins and
air conditioning condenser for restrictions.
(15) Verify that the intake manifold air tempera-
ture sensor wire connector is firmly connected to har-
ness connector (Fig. 15).(16) Verify that MAP sensor electrical connector is
firmly connected to MAP sensor (Fig. 16).
(17) Verify that fuel injector wire harness connec-
tors are firmly connected to injectors in the correct
order. Each harness connector is numerically tagged
with the injector number (INJ 1, INJ 2 etc.) of its
corresponding fuel injector and cylinder number.
(18) Verify harness connectors are firmly con-
nected to idle air control (IAC) motor and throttle
position sensor (TPS).
(19) Verify that wire harness connector is firmly
connected to the engine coolant temperature sensor
(Fig. 17).
Fig. 14 Ignition Coil PackÐ8.0L Engine
Fig. 15 Air Temperature SensorÐ8.0L Engine
1 - INTAKE MANIFOLD AIR TEMP. SENSOR
2 - INTAKE MANIFOLD
Fig. 16 Map Sensor Ð8.0L Engine
1 - MAP SENSOR
2 - MOUNTING BOLTS
3 - THROTTLE BODY
Fig. 17 Engine Coolant Temperature SensorÐ8.0L
Engine
1 - ENGINE COOLANT TEMP. SENSOR
2 - THERMOSTAT HOUSING
3 - GENERATOR
BR/BEFUEL INJECTION - GASOLINE 14 - 33
FUEL INJECTION - GASOLINE (Continued)
Page 1336 of 2255

INSTALLATION
(1) Position pedal/bracket assembly over pivot pin
(Fig. 22) .
(2) Install two new pivots/bushings. Using large
pliers, press both bushings together until they bot-
tom on sides of pedal/bracket assembly. Bushing
retaining ears will snap into position when properly
installed.
(3) From inside vehicle, hold up accelerator pedal.
Install throttle cable core wire and plastic cable
retainer into and through upper end of pedal arm
(the plastic retainer is snapped into pedal arm).
When installing plastic retainer to accelerator pedal
arm, note index tab on pedal arm (Fig. 21) . Align
index slot on plastic cable retainer to this index tab.
CRANKSHAFT POSITION
SENSOR
DESCRIPTION
DESCRIPTION - 5.9L
The Crankshaft Position (CKP) sensor is located
near the outer edge of the flywheel (starter ringear).
DESCRIPTION - 8.0L
The Crankshaft Position (CKP) 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. 23).
OPERATION
OPERATION - 5.9L
Engine speed and crankshaft position are provided
through the CKP sensor. The sensor generates pulses
that are the input sent to the Powertrain Control
Module (PCM). The PCM interprets the sensor input
to determine the crankshaft position. The PCM then
uses this position, along with other inputs, to deter-
mine injector sequence and ignition timing.
The sensor is a hall effect device combined with an
internal magnet. It is also sensitive to steel within a
certain distance from it.
On 5.9L V-8 engines, the flywheel/drive plate has 8
single notches, spaced every 45 degrees, at its outer
edge (Fig. 24).
The notches cause a pulse to be generated when
they pass under the sensor. The pulses are the input
to the PCM. For each engine revolution, there are 8
pulses generated on V-8 engines.
The engine will not operate if the PCM does not
receive a CKP sensor input.
Fig. 22 Accelerator PedalÐRemoval or Installation
1 - PEDAL MOUNTING BRACKET
2 - PIVOTS/BUSHINGS
3 - PEDAL/BRACKET
4 - PIVOT PIN
Fig. 23 CKP Sensor LocationÐ8.0L V-10 Engine
1 - CRANKSHAFT POSITION SENSOR
2 - HOLE
3 - OIL FILTER
4 - PLASTIC TIE STRAP
5 - PIGTAIL HARNESS
BR/BEFUEL INJECTION - GASOLINE 14 - 37
ACCELERATOR PEDAL (Continued)
Page 1337 of 2255

OPERATION - 8.0L
The Crankshaft Position (CKP) sensor detects
notches machined into the middle of the crankshaft
(Fig. 25).There are five sets of notches. Each set contains
two notches. Basic ignition timing is determined by
the position of the last notch in each set of notches.
Once the Powertrain Control Module (PCM) senses
the last notch, it will determine crankshaft position
(which piston will next be at Top Dead Center). An
input from the camshaft position sensor is also
needed. It may take the module up to one complete
engine revolution to determine crankshaft position
during engine cranking.
The PCM uses the signal from the camshaft posi-
tion sensor to determine fuel injector sequence. Once
crankshaft position has been determined, the PCM
begins energizing a ground circuit to each fuel injec-
tor to provide injector operation.
REMOVAL
REMOVAL - 5.9L
The sensor is bolted to the top of the cylinder block
near the rear of right cylinder head (Fig. 26).
(1) Remove the air cleaner intake tube.
(2) Disconnect crankshaft position sensor pigtail
harness from main wiring harness.
(3) Remove two sensor (recessed hex head) mount-
ing bolts (Fig. 26).
(4) Remove sensor from engine.
Fig. 24 CKP Sensor OperationÐ5.9L Engine
1 - CRANKSHAFT POSITION SENSOR
2 - NOTCHES
3 - FLYWHEEL
Fig. 25 CKP Sensor OperationÐ8.0L V-10 Engine
1 - CRANKSHAFT NOTCHES
2 - CRANKSHAFT
3 - CRANKSHAFT POSITION SENSOR
Fig. 26 Crankshaft Position Sensor
1 - GROMMET
2 - MOUNTING BOLTS (2)
3 - CRANKSHAFT POSITION SENSOR
4 - RIGHT EXHAUST MANIFOLD
5 - TRANSMISSION BELL HOUSING
14 - 38 FUEL INJECTION - GASOLINEBR/BE
CRANKSHAFT POSITION SENSOR (Continued)
Page 1339 of 2255

CAUTION: Before tightening sensor mounting bolt,
be sure sensor is completely flush to cylinder block
(Fig. 28). 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
(5) Install new plastic tie strap (Fig. 27) to secure
sensor pigtail harness to side of engine block. Thread
tie strap through casting hole on cylinder block.
FUEL PUMP RELAY
DESCRIPTION
The 5±pin, 12±volt, fuel pump relay is located in
the Power Distribution Center (PDC). Refer to the
label on the PDC cover for relay location.
OPERATION
The Powertrain Control Module (PCM) energizes
the electric fuel pump through the fuel pump relay.
The fuel pump relay is energized by first applying
battery voltage to it when the ignition key is turned
ON, and then applying a ground signal to the relay
from the PCM.
Whenever the ignition key is turned ON, the elec-
tric fuel pump will operate. But, the PCM will shut-
down the ground circuit to the fuel pump relay in
approximately 1±3 seconds unless the engine is oper-
ating or the starter motor is engaged.
REMOVAL
The fuel pump relay is located in the Power Distri-
bution Center (PDC) (Fig. 30). Refer to label on PDC
cover for relay location.
(1) Remove PDC cover.
(2) Remove relay from PDC.
(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.
INSTALLATION
The fuel pump relay is located in the Power Distri-
bution Center (PDC) (Fig. 30) . Refer to label on PDC
cover for relay location.
(1) Install relay to PDC.
(2) Install cover to PDC.
IDLE AIR CONTROL MOTOR
DESCRIPTION
The IAC stepper motor is mounted to the throttle
body, and regulates the amount of air bypassing the
control of the throttle plate. As engine loads and
ambient temperatures change, engine rpm changes.
A pintle on the IAC stepper motor protrudes into a
passage in the throttle body, controlling air flow
through the passage. The IAC is controlled by the
Powertrain Control Module (PCM) to maintain the
target engine idle speed.
OPERATION
At idle, engine speed can be increased by retract-
ing the IAC motor pintle and allowing more air to
pass through the port, or it can be decreased by
restricting the passage with the pintle and diminish-
ing the amount of air bypassing the throttle plate.
The IAC is called a stepper motor because it is
moved (rotated) in steps, or increments. Opening the
IAC opens an air passage around the throttle blade
which increases RPM.
The PCM uses the IAC motor to control idle speed
(along with timing) and to reach a desired MAP dur-
ing decel (keep engine from stalling).
The IAC motor has 4 wires with 4 circuits. Two of
the wires are for 12 volts and ground to supply elec-
trical current to the motor windings to operate the
stepper motor in one direction. The other 2 wires are
also for 12 volts and ground to supply electrical cur-
rent to operate the stepper motor in the opposite
direction.
Fig. 30 Power Distribution Center (PDC)
1 - POWER DISTRIBUTION CENTER (PDC)
14 - 40 FUEL INJECTION - GASOLINEBR/BE
CRANKSHAFT POSITION SENSOR (Continued)
Page 1349 of 2255

INSTALLATION
(1)5.9L Engines:
(a) Rotate and hold the throttle cam in the full
wide open position. Snap the cable end onto lever
pin (Fig. 43).
(b) Connect cable to throttle body mounting
bracket (push down and lock).
(c) Connect cable to fan shroud routing clip.
(2)8.0L V-10 Engine:
(a) Connect cable end socket to throttle body
lever ball (snaps on) (Fig. 44).
(b) Connect cable to throttle body mounting
bracket (push down and lock).
(3) Install the remaining cable housing end into
and through the dash panel opening (snaps into posi-
tion). The two plastic pinch tabs (Fig. 21) should lock
the cable to dash panel.
(4) From inside the vehicle, hold up the accelera-
tor pedal. Install the throttle cable core wire and
plastic cable retainer into and through the upper end
of the pedal arm (the plastic retainer is snapped into
the pedal arm). When installing the plastic retainer
to the accelerator pedal arm, note the index tab on
the pedal arm (Fig. 21). Align the index slot on the
plastic cable retainer to this index tab.
THROTTLE POSITION SENSOR
DESCRIPTION
The 3±wire Throttle Position Sensor (TPS) is
mounted on the throttle body and is connected to the
throttle blade.
OPERATION
The TPS is a 3±wire variable resistor that provides
the Powertrain Control Module (PCM) with an input
signal (voltage) that represents the throttle blade
position of the throttle body. The sensor is connected
to the throttle blade shaft. As the position of the
throttle blade changes, the resistance (output volt-
age) of the TPS changes.
The PCM supplies approximately 5 volts to the
TPS. The TPS output voltage (input signal to the
PCM) represents the throttle blade position. The
PCM receives an input signal voltage from the TPS.
This will vary in an approximate range of from .26
volts at minimum throttle opening (idle), to 4.49 volts
at wide open throttle. Along with inputs from other
sensors, the PCM uses the TPS input to determine
current engine operating conditions. In response to
engine operating conditions, the PCM will adjust fuel
injector pulse width and ignition timing.
The PCM needs to identify the actions and position
of the throttle blade at all times. This information is
needed to assist in performing the following calcula-
tions:
²Ignition timing advance
²Fuel injection pulse-width
²Idle (learned value or minimum TPS)
²Off-idle (0.06 volt)
²Wide Open Throttle (WOT) open loop (2.608
volts above learned idle voltage)
²Deceleration fuel lean out
²Fuel cutoff during cranking at WOT (2.608 volts
above learned idle voltage)
²A/C WOT cutoff (certain automatic transmis-
sions only)
REMOVAL
REMOVAL - 5.9L
The TPS is located on the side of the throttle body.
(1) Remove air intake tube at throttle body.
(2) Disconnect TPS electrical connector.
(3) Remove two TPS mounting bolts (Fig. 46).
(4) Remove TPS from throttle body.
REMOVAL - 8.0L
The TPS is located on the side of the throttle body
(Fig. 47).
(1) Remove air intake tube at air cleaner housing.
(2) Remove the air cleaner cover.
(3) Remove the 4 air cleaner housing mounting
nuts and remove housing from throttle body.
(4) Disconnect TPS electrical connector.
(5) Remove two TPS mounting bolts (Fig. 47).
(6) Remove TPS from throttle body.
Fig. 45 Cable Release
1-TAB
14 - 50 FUEL INJECTION - GASOLINEBR/BE
THROTTLE CONTROL CABLE (Continued)
Page 1351 of 2255

(2) Tighten bolts to 7 N´m (60 in. lbs.) torque.
(3) Manually operate the throttle control lever by
hand to check for any binding of the TPS.
(4) Connect TPS electrical connector to TPS.
(5) Install air cleaner housing to throttle body.
(6) Install 4 air cleaner housing mounting nuts.
Tighten nuts to 11 N´m (96 in. lbs.) torque.
(7) Install air cleaner housing cover.
(8) Install air intake tube to cover.
FUEL INJECTOR
DESCRIPTION
A separate fuel injector (Fig. 50) is used for each
individual cylinder.
OPERATION
OPERATION
The fuel injectors are electrical solenoids. The
injector contains a pintle that closes off an orifice at
the nozzle end. When electric current is supplied to
the injector, the armature and needle move a short
distance against a spring, allowing fuel to flow out
the orifice. Because the fuel is under high pressure, a
fine spray is developed in the shape of a pencil
stream. The spraying action atomizes the fuel, add-
ing it to the air entering the combustion chamber.
An individual fuel injector is used for each individ-
ual cylinder. The top (fuel entry) end of the injector is
attached into an opening on the fuel rail.The nozzle (outlet) ends of the injectors are posi-
tioned into openings in the intake manifold just
above the intake valve ports of the cylinder head.
The engine wiring harness connector for each fuel
injector is equipped with an attached numerical tag
(INJ 1, INJ 2 etc.). This is used to identify each fuel
injector.
The injectors are energized individually in a
sequential order by the Powertrain Control Module
(PCM). The PCM will adjust injector pulse width by
switching the ground path to each individual injector
on and off. Injector pulse width is the period of time
that the injector is energized. The PCM will adjust
injector pulse width based on various inputs it
receives.
Battery voltage is supplied to the injectors through
the ASD relay.
The PCM determines injector pulse width based on
various inputs.
OPERATION - PCM OUTPUT
The nozzle ends of the injectors are positioned into
openings in the intake manifold just above the intake
valve ports of the cylinder head. The engine wiring
harness connector for each fuel injector is equipped
with an attached numerical tag (INJ 1, INJ 2 etc.).
This is used to identify each fuel injector with its
respective cylinder number.
The injectors are energized individually in a
sequential order by the Powertrain Control Module
(PCM). The PCM will adjust injector pulse width by
switching the ground path to each individual injector
on and off. Injector pulse width is the period of time
that the injector is energized. The PCM will adjust
injector pulse width based on various inputs it
receives.
Battery voltage (12 volts +) is supplied to the injec-
tors through the ASD relay. The ASD relay will shut-
down the 12 volt power source to the fuel injectors if
the PCM senses the ignition is on, but the engine is
not running. This occurs after the engine has not
been running for approximately 1.8 seconds.
The PCM determines injector on-time (pulse width)
based on various inputs.
Fig. 50 Fuel Injector
1 - FUEL INJECTOR
2 - NOZZLE
3 - TOP (FUEL ENTRY)
14 - 52 FUEL INJECTION - GASOLINEBR/BE
THROTTLE POSITION SENSOR (Continued)
Page 1363 of 2255

REMOVAL
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. 14) serves two pur-
poses. One is topartiallydrain filter housing of
excess water. The other is tocompletelydrain hous-
ing for fuel filter, drain valve, heater element or
water-in-fuel sensor replacement.
The filter housing should be partially drained
whenever water-in-fuel warning lamp remains illumi-
nated. (Note that lamp will be illuminated for
approximately two seconds when ignition key is ini-
tially placed in ON position for a bulb check).
(1) A drain hose is located at bottom of drain valve
(Fig. 14). Place drain pan under drain hose.
(2)With engine not running,pull drain valve
handle upward to OPEN (DRAIN) position (Fig. 14).
Hold drain valve open until all water and contami-
nants have been removed and clean fuel exits drain
hose.
(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
downward to CLOSE position (Fig. 14).
(5)Fuel Filter Replacement:The fuel filter is
located inside of the fuel filter housing (Fig. 15).
(a) Unscrew and remove fuel filter cap at top of
fuel filter housing (Fig. 14). To unscrew, attach tool
to 6±sided hex center of cap. Do not attempt to
loosen cap at outer edge. The fuel filter cap is
designed to remove filter while pulling up on cap.
(b) Remove o-ring (Fig. 15) from filter cap and
discard.
(c) The filter is retained to the cap with a series
of locking fingers. Carefully pry back a few of the
fingers to unlock filter from cap.
(6)Water-In-Fuel (WIF) Sensor Replacement:
The WIF sensor is located on the side of the fuel fil-
ter housing (Fig. 15).
(a) Disconnect electrical connector at sensor
(Fig. 16).
(b) Unscrew sensor from filter housing.
Fig. 14 Water Drain Valve and Drain Hose
1 - FUEL FILTER CAP
2 - DRAIN VALVE HANDLE
3 - DRAIN HOSE
4 - FUEL FILTER/WATER SEPARATOR
Fig. 15 Fuel Filter/Water Separator Components
1 - CAP
2 - O-RING
3 - FUEL FILTER
4 - FUEL HEATER ELEMENT
5 - HOUSING
6 - O-RINGS
7 - DRAIN VALVE
8 - FUEL HEATER THERMOSTAT
9 - WATER-IN-FUEL SENSOR
14 - 64 FUEL DELIVERY - DIESELBR/BE
FUEL FILTER / WATER SEPARATOR (Continued)