DODGE RAM 2002 Service Repair Manual

REMOVAL
WARNING: THE FUEL SYSTEM IS UNDER A CON-
STANT PRESSURE (EVEN WITH THE ENGINE OFF).
BEFORE SERVICING THE CHECK VALVE, FUEL
SYSTEM PRESSURE MUST BE RELEASED (GASO-
LINE POWERED ENGINES ONLY). REFER TO THE
FUEL PRESSURE RELEASE PROCEDURE IN
GROUP 14, FUEL SYSTEM.
(1)Diesel Powered Engine:One checkr valve is
used. The valve is located on top of fuel tank module
(Fig. 40) and may be serviced separately.
(a) Disconnect both negative battery cables at
both batteries.
(b) Remove fuel filler cap and drain fuel tank.
(c) Remove fuel tank. Refer to Fuel Tank Remov-
al/Installation in Fuel System.
(d) The check valve is seated into a rubber
grommet. Remove valve by prying one side upward
and then roll valve out of grommet.
(e) Discard old grommet.
(2)Gasoline Powered Engines:
If equipped with
a 26 or 34 gallon fuel tank, two check valves are used.
One of the valves is permanently mounted to top of
fuel tank (Fig. 41). If replacement of this particular
valve is necessary, fuel tank must be replaced. Refer
to Fuel Tank Removal/Installation in Group 14, Fuel
System. The other check valve is located on top of fuel
pump module (Fig. 41). This valve may be serviced
separately. Refer to following steps for procedures.
Fig. 39 Check Valve LocationsÐGas Powered with
35 Gallon Tank
1 - FRONT FUEL TANK CHECK VALVE
2 - FUEL PUMP MODULE
3 - REAR FUEL TANK CHECK VALVE
4 - FUEL TANK
Fig. 40 Check Valve Location - Diesel Powered
1 - AUXILIARY CAPPED FITTING
2 - FUEL PUMP MODULE
3 - FUEL SUPPLY/RETURN FITTINGS
4 - ELECTRICAL CONNECTOR
5 - LOCKNUT
6 - FUEL TANK CHECK VALVE
Fig. 41 Check Valve Locations - Gas Powered -
26/34 Gallon Tank
1 - FUEL FILTER/PRESSURE REGULATOR
2 - FUEL SUPPLY FITTING
3 - REAR FUEL TANK CHECK VALVE
4 - ELECTRICAL CONNECTOR
5 - FUEL PUMP MODULE
6 - FRONT FUEL TANK CHECK VALVE
7 - LOCKNUT
14 - 22 FUEL DELIVERY - GASOLINEBR/BE
FUEL TANK CHECK VALVE (Continued)

If equipped with a 35 gallon fuel tank, two check
valves are also used, but both valves are permanently
mounted to top of fuel tank (Fig. 42). If replacement is
necessary, fuel tank must be replaced. Refer to Fuel
Tank Removal/Installation in Group 14, Fuel System.
(a) Disconnect negative battery cable at battery.
(b) Remove fuel filler cap and drain fuel tank.
(c) Remove fuel tank. Refer to Fuel Tank Remov-
al/Installation in Fuel System.
(d) Disconnect tube (line) at valve.
(e) The check valve is seated into a rubber grom-
met. Remove valve by prying one side upward and
then roll valve out of grommet.
(f) Discard old grommet.
INSTALLATION
(1) Install new grommet into fuel pump (or fuel
tank) module.
(2) Using finger pressure only, press valve into
place.
(3) Install fuel tank. Refer to Fuel Tank Installa-
tion.
(4) Fill fuel tank. Install fuel tank filler cap.
(5) Connect negative battery cable(s).
(6) Start vehicle and check for leaks.
INLET FILTER
REMOVAL
The fuel pump inlet filter (strainer) is located on
the bottom of the fuel pump module (Fig. 43). The
fuel pump module is located inside of fuel tank.
(1) Remove fuel tank. Refer to Fuel Tank Removal/
Installation.
(2) Remove fuel pump module. Refer to Fuel Pump
Module Removal/Installation.
(3) Remove filter by carefully prying 2 lock tabs at
bottom of module with 2 screwdrivers. Filter is
snapped to module.
(4) Clean bottom of pump module.
INSTALLATION
The fuel pump inlet filter (strainer) is located on
the bottom of the fuel pump module (Fig. 43) . The
fuel pump module is located inside of fuel tank.
(1) Snap new filter to bottom of module. Be sure
o-ring is in correct position.
(2) Install fuel pump module. Refer to Fuel Pump
Module Removal/Installation.
(3) Install fuel tank. Refer to Fuel Tank Removal/
Installation.
Fig. 42 Check Valve Locations - Gas Powered with
35 Gallon Tank
1 - FRONT FUEL TANK CHECK VALVE
2 - FUEL PUMP MODULE
3 - REAR FUEL TANK CHECK VALVE
4 - FUEL TANK
Fig. 43 Fuel Pump Inlet Filter
1 - FUEL PUMP INLET FILTER
2 - LOCK TABS (2)
3 - FUEL PUMP MODULE (BOTTOM)
BR/BEFUEL DELIVERY - GASOLINE 14 - 23
FUEL TANK CHECK VALVE (Continued)

QUICK CONNECT FITTING
DESCRIPTION
Different types of quick-connect fittings are used to
attach various fuel system components, lines and
tubes. These are: a single-tab type, a two-tab type or
a plastic retainer ring type. Some are equipped with
safety latch clips. Some may require the use of a spe-
cial tool for disconnection and removal. Refer to
Quick-Connect Fittings Removal/Installation for more
information.
CAUTION: The interior components (o-rings, clips)
of quick-connect fittings are not serviced sepa-
rately, but new plastic spacers are available for
some types. If service parts are not available, do
not attempt to repair the damaged fitting or fuel line
(tube). If repair is necessary, replace the complete
fuel line (tube) assembly.
STANDARD PROCEDURE - QUICK-CONNECT
FITTINGS
Also refer to Fuel Tubes/Lines/Hoses and Clamps.
Different types of quick-connect fittings are used to
attach various fuel system components, lines and
tubes. These are: a single-tab type, a two-tab type or
a plastic retainer ring type. Safety latch clips are
used on certain components/lines. Certain fittings
may require use of a special tool for disconnection.
DISCONNECTING
WARNING: THE FUEL SYSTEM IS UNDER A CON-
STANT PRESSURE (EVEN WITH ENGINE OFF).
BEFORE SERVICING ANY FUEL SYSTEM HOSE,
FITTING OR LINE, FUEL SYSTEM PRESSURE MUST
BE RELEASED. REFER TO FUEL SYSTEM PRES-
SURE RELEASE PROCEDURE.
CAUTION: The interior components (o-rings, spac-
ers) of some types of quick-connect fitting are not
serviced separately. If service parts are not avail-
able, do not attempt to repair a damaged fitting or
fuel line. If repair is necessary, replace complete
fuel line assembly.(1) Perform fuel pressure release procedure. Refer
to Fuel Pressure Release Procedure.
(2) Disconnect negative battery cable from battery.
(3) Clean fitting of any foreign material before dis-
assembly.
(4)2±Button Type Fitting:This type of fitting is
equipped with a push-button located on each side of
quick-connect fitting (Fig. 44). Press on both buttons
simultaneously for removal.
(5)Single-Tab Type Fitting:This type of fitting
is equipped with a single pull tab (Fig. 45). The tab
is removable. After tab is removed, quick-connect fit-
ting can be separated from fuel system component.
(a) Press release tab on side of fitting to release
pull tab (Fig. 46).If release tab is not pressed
prior to releasing pull tab, pull tab will be
damaged.
(b) While pressing release tab on side of fitting,
use screwdriver to pry up pull tab (Fig. 46).
(c) Raise pull tab until it separates from quick-
connect fitting (Fig. 47).
(6)Two-Tab Type Fitting:This type of fitting is
equipped with tabs located on both sides of fitting
(Fig. 48). The tabs are supplied for disconnecting
quick-connect fitting from component being serviced.
Fig. 44 2-BUTTON TYPE FITTING
1 - QUICK-CONNECT FITTING
2 - PUSH-BUTTONS (2)
14 - 24 FUEL DELIVERY - GASOLINEBR/BE

(a) To disconnect quick-connect fitting, squeeze
plastic retainer tabs (Fig. 48) against sides of
quick-connect fitting with your fingers. Tool use is
not required for removal and may damage plastic
retainer.
(b) Pull fitting from fuel system component
being serviced.
(c) The plastic retainer will remain on compo-
nent being serviced after fitting is disconnected.
The o-rings and spacer will remain in quick-con-
nect fitting connector body.(7)Plastic Retainer Ring Type Fitting:This
type of fitting can be identified by the use of a full-
round plastic retainer ring (Fig. 49) usually black in
color.
(a) To release fuel system component from quick-
connect fitting, firmly push fitting towards compo-
nent being serviced while firmly pushing plastic
retainer ring into fitting (Fig. 49). With plastic ring
depressed, pull fitting from component.The plas-
tic retainer ring must be pressed squarely
into fitting body. If this retainer is cocked
during removal, it may be difficult to discon-
nect fitting. Use an open-end wrench on
shoulder of plastic retainer ring to aid in dis-
connection.
Fig. 45 SINGLE-TAB TYPE FITTING
1 - PULL TAB
2 - QUICK-CONNECT FITTING
3 - PRESS HERE TO REMOVE PULL TAB
4 - INSERTED TUBE END
Fig. 46 DISCONNECTING SINGLE-TAB TYPE
FITTING
1 - PULL TAB
2 - SCREWDRIVER
3 - QUICK-CONNECT FITTING
Fig. 47 REMOVING PULL TAB
1 - FUEL TUBE OR FUEL SYSTEM COMPONENT
2 - PULL TAB
3 - QUICK-CONNECT FITTING
4 - FUEL TUBE STOP
Fig. 48 TYPICAL 2±TAB TYPE FITTING
1 - TAB(S)
2 - QUICK-CONNECT FITTING
BR/BEFUEL DELIVERY - GASOLINE 14 - 25
QUICK CONNECT FITTING (Continued)

(b) After disconnection, plastic retainer ring will
remain with quick-connect fitting connector body.
(c) Inspect fitting connector body, plastic retainer
ring and fuel system component for damage.
Replace as necessary.
Fig. 49 PLASTIC RETAINER RING TYPE FITTING
1 - FUEL TUBE
2 - QUICK CONNECT FITTING
3 - PUSH
4 - PLASTIC RETAINER
5 - PUSH
6 - PUSH
7 - PUSH
8 - PUSH
Fig. 50 LATCH CLIP-TYPE 1
1 - TETHER STRAP
2 - FUEL LINE
3 - SCREWDRIVER
4 - LATCH CLIP
5 - FUEL RAIL
Fig. 51 LATCH CLIP-TYPE 2
1 - LATCH CLIP
Fig. 52 FUEL LINE DISCONNECTION USING
SPECIAL TOOL
1 - SPECIAL FUEL LINE TOOL
2 - FUEL LINE
3 - FUEL RAIL
14 - 26 FUEL DELIVERY - GASOLINEBR/BE
QUICK CONNECT FITTING (Continued)

(8)Latch Clips:Depending on vehicle model and
engine, 2 different types of safety latch clips are used
(Fig. 50) or (Fig. 51). Type-1 is tethered to fuel line
and type-2 is not. A special tool will be necessary to
disconnect fuel line after latch clip is removed. The
latch clip may be used on certain fuel line/fuel rail
connection, or to join fuel lines together.
(a) Type 1: Pry up on latch clip with a screw-
driver (Fig. 50).
(b) Type 2: Separate and unlatch 2 small arms
on end of clip (Fig. 51) and swing away from fuel
line.
(c) Slide latch clip toward fuel rail while lifting
with screwdriver.
(d) Insert special fuel line removal tool (Snap-On
number FIH 9055-1 or equivalent) into fuel line
(Fig. 52). Use tool to release locking fingers in end
of line.
(e) With special tool still inserted, pull fuel line
from fuel rail.
(f) After disconnection, locking fingers will
remain within quick-connect fitting at end of fuel
line.
(9) Disconnect quick-connect fitting from fuel sys-
tem component being serviced.CONNECTING
(1) Inspect quick-connect fitting body and fuel sys-
tem component for damage. Replace as necessary.
(2) Prior to connecting quick-connect fitting to
component being serviced, check condition of fitting
and component. Clean parts with a lint-free cloth.
Lubricate with clean engine oil.
(3) Insert quick-connect fitting into fuel tube or
fuel system component until built-on stop on fuel
tube or component rests against back of fitting.
(4) Continue pushing until a click is felt.
(5) Single-tab type fitting: Push new tab down
until it locks into place in quick-connect fitting.
(6) Verify a locked condition by firmly pulling on
fuel tube and fitting (15-30 lbs.).
(7) Latch Clip Equipped: Install latch clip (snaps
into position).If latch clip will not fit, this indi-
cates fuel line is not properly installed to fuel
rail (or other fuel line). Recheck fuel line con-
nection.
(8) Connect negative cable to battery.
(9) Start engine and check for leaks.
BR/BEFUEL DELIVERY - GASOLINE 14 - 27
QUICK CONNECT FITTING (Continued)

FUEL INJECTION - GASOLINE
TABLE OF CONTENTS
page page
FUEL INJECTION - GASOLINE
DIAGNOSIS AND TESTING
VISUAL INSPECTIONÐ5.9L ENGINES.....29
VISUAL INSPECTIONÐ8.0L ENGINE......32
SPECIFICATIONS - TORQUE - GAS FUEL
INJECTION..........................35
SPECIAL TOOLS
FUEL SYSTEM.......................35
ACCELERATOR PEDAL
REMOVAL.............................36
INSTALLATION.........................37
CRANKSHAFT POSITION SENSOR
DESCRIPTION
DESCRIPTION - 5.9L...................37
DESCRIPTION - 8.0L...................37
OPERATION
OPERATION - 5.9L....................37
OPERATION - 8.0L....................38
REMOVAL
REMOVAL - 5.9L......................38
REMOVAL - 8.0L......................39
INSTALLATION
INSTALLATION - 5.9L..................39
INSTALLATION - 8.0L..................39
FUEL PUMP RELAY
DESCRIPTION.........................40
OPERATION...........................40
REMOVAL.............................40
INSTALLATION.........................40
IDLE AIR CONTROL MOTOR
DESCRIPTION.........................40
OPERATION...........................40
REMOVAL
REMOVAL - 5.9L......................41
REMOVAL - 8.0L......................41
INSTALLATION
INSTALLATION - 5.9L..................42
INSTALLATION - 8.0L..................42
INTAKE AIR TEMPERATURE SENSOR
DESCRIPTION - 5.9L/8.0L.................42
OPERATION - 5.9L/8.0L..................42
REMOVAL
REMOVAL - 5.9L......................42
REMOVAL - 8.0L......................43
INSTALLATION
INSTALLATION - 5.9L..................43
INSTALLATION - 8.0L..................43MANIFOLD ABSOLUTE PRESSURE SENSOR
DESCRIPTION - 5.9L/8.0L.................43
OPERATION - 5.9L/8.0L..................43
REMOVAL
REMOVAL - 5.9L......................44
REMOVAL - 8.0L......................44
INSTALLATION
INSTALLATION - 5.9L..................45
INSTALLATION - 8.0L..................45
O2 SENSOR
DESCRIPTION.........................45
OPERATION...........................45
REMOVAL.............................46
INSTALLATION.........................47
PTO SWITCH
DESCRIPTION.........................47
OPERATION...........................47
THROTTLE BODY
DESCRIPTION.........................47
OPERATION...........................47
REMOVAL
REMOVAL - 5.9L......................47
REMOVAL - 8.0L......................47
INSTALLATION
INSTALLATION - 5.9L..................48
INSTALLATION - 8.0L..................49
THROTTLE CONTROL CABLE
REMOVAL.............................49
INSTALLATION.........................50
THROTTLE POSITION SENSOR
DESCRIPTION.........................50
OPERATION...........................50
REMOVAL
REMOVAL - 5.9L......................50
REMOVAL - 8.0L......................50
INSTALLATION
INSTALLATION - 5.9L..................51
INSTALLATION - 8.0L..................51
FUEL INJECTOR
DESCRIPTION.........................52
OPERATION
OPERATION.........................52
OPERATION - PCM OUTPUT............52
DIAGNOSIS AND TESTING - FUEL INJECTOR . 53
REMOVAL.............................53
INSTALLATION.........................53
14 - 28 FUEL INJECTION - GASOLINEBR/BE

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

(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.
(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. 5).
(16) Verify that MAP sensor electrical connector is
firmly connected to MAP sensor (Fig. 6). Also verify
that rubber L-shaped fitting from MAP sensor to the
throttle body is firmly connected (Fig. 7).
(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, throttle posi-
tion sensor (TPS) and manifold absolute pressure
(MAP) sensor (Fig. 6).(19) Verify that wire harness connector is firmly
connected to the engine coolant temperature sensor
(Fig. 8).
(20) Raise and support the vehicle.
(21) Verify oxygen sensor wire connectors are
firmly connected to the sensors. Inspect sensors and
connectors for damage (Fig. 9), (Fig. 10) or (Fig. 11).
Fig. 4 PCV Valve
1 - P C V VA LV E
2 - PCV VALVE HOSE CONNECTIONS
Fig. 5 Air Temperature
1 - INTAKE MANIFOLD AIR TEMPERATURE SENSOR
2 - ELECTRICAL CONNECTOR
Fig. 6 Sensor and IAC Motor LocationÐTypical (V-8
Shown)
1 - MAP SENSOR
2 - IDLE AIR CONTROL MOTOR
3 - THROTTLE POSITION SENSOR
14 - 30 FUEL INJECTION - GASOLINEBR/BE
FUEL INJECTION - GASOLINE (Continued)

(22) Inspect for pinched or leaking fuel tubes.
Inspect for pinched, cracked or leaking fuel hoses.
(23) Inspect for exhaust system restrictions such
as pinched exhaust pipes, collapsed muffler or
plugged catalytic convertor.
(24) If equipped with automatic transmission, ver-
ify that electrical harness is firmly connected to park/
neutral switch. Refer to 21, Automatic Transmission.(25) Verify electrical harness is firmly connected to
rear wheel speed sensor. Verify rear wheel speed sen-
sor is firmly attached to rear axle with proper air
gap. Refer to 5, Brakes for information.
(26) If equipped with 4±wheel antilock brake sys-
tem, verify electrical harness is firmly connected to
each front wheel speed sensor. Verify both front
wheel speed sensors are firmly attached. Refer to 5,
Brakes for information.
(27) Verify that fuel pump/gauge sender unit wire
connector is firmly connected to harness connector.
(28) Inspect fuel hoses at fuel pump/gauge sender
unit for cracks or leaks.
Fig. 7 Rubber L-Shaped FittingÐMAP Sensor-to-
Throttle BodyÐ5.9L Engines
1 - MAP SENSOR
2 - RUBBER FITTING
3 - IDLE AIR PASSAGE
Fig. 8 Engine Coolant Temperature
1 - GENERATOR
2 - A/C COMPRESSOR
3 - ENGINE COOLANT TEMPERATURE SENSOR
4 - ELEC. CONN.
Fig. 9 Left/Right Oxygen SensorsÐHDC Engines
1 - DUAL OXYGEN SENSORS
2 - TOP OF TRANSMISSION
Fig. 10 Pre-Catalyst/Post-Catalyst Sensors
1 - POST CATALYST OXYGEN SENSOR (1/3)
2 - PRE-CATALYST OXYGEN SENSOR (1/2)
BR/BEFUEL INJECTION - GASOLINE 14 - 31
FUEL INJECTION - GASOLINE (Continued)