1998 DODGE RAM 1500 Body

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.
(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. 19).
(5) Drain fuel tank by attaching drain hose from
an approved draining station to auxiliary fitting on
top of tank module (Fig. 19).
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. 20) and
remove both tank support straps.
(4) Carefully lower tank a few inches and discon-
nect fuel pump module electrical connector (Fig. 19)
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. 19). Refer to Quick-Connect Fit-
tings for procedures.
(6) Continue to lower tank for removal.
(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
at top of tank.
(5) Connect fuel supply and return lines to tank
module.
(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
of module.
Fig. 19 FUEL TANK MODULE - 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
14 - 62 FUEL DELIVERY - DIESELDR

CAUTION: Do not attempt to remove sensor from
its mounting bracket as electronic calibration will
be destroyed (sensor-to-bracket mounting screws
are permanently attached). Two accelerator lever
set screws (Fig. 3) are used to position lever. Do
not attempt to alter positions of these set screws as
electronic calibration will be destroyed.
(1) Disconnect both negative battery cables at both
batteries.
(2) Remove cable cover (Fig. 1). Cable cover is
attached with 2 Phillips screws, 2 plastic retention
clips and 2 push tabs (Fig. 1). Remove 2 Phillips
screws and carefully pry out 2 retention clips. After
clip removal, push rearward on front tab, and
upward on lower tab for cover removal.
(3) Using finger pressure only, disconnect end of
speed control servo cable from throttle lever pin by
pulling forward on connector while holding lever
rearward (Fig. 2).DO NOT try to pull connector
off perpendicular to lever pin. Connector will
be broken.
(4) Using two small screwdrivers, pry throttle
cable connector socket from throttle lever ball (Fig.
2).Be very careful not to bend throttle lever
arm.
(5) Disconnect transmission control cable at lever
arm (if equipped). Refer to 21, Transmission.
(6) Squeeze pinch tabs on speed control cable (Fig.
2) and pull cable rearward to remove from cable
mounting bracket.
(7) Squeeze pinch tabs on throttle cable (Fig. 2)
and pull cable rearward to remove from cable mount-
ing bracket.
(8) Refer to 21, Transmission for transmission con-
trol cable removal procedures.
(9) Disconnect wiring harness clip (Fig. 3) at bot-
tom of bracket.
(10) Remove 6 mounting bolts (Fig. 3) and par-
tially remove APPS assembly from engine. After
assembly is partially removed, disconnect electrical
connector from bottom of sensor by pushing on con-
nector tab (Fig. 4).
(11) Remove APPS assembly from engine.
Battery Tray Mounted Sensor :
The APPS is serviced (replaced) as one assembly
including the sensor, plastic housing and cable. The
APPS assembly is located under the left (drivers
side) vehicle battery tray (Fig. 5). Access to APPS is
gained from over top of left / front tire.
(1) Disconnect negative battery cable at battery.
(2) Disconnect APPS cable at accelerator pedal.
Refer to Accelerator Pedal Removal / Installation.
(3) Remove wheel house liner at left / front wheel.
Refer to Body.(4) Gain access to APPS electrical connector by
opening swing-down door (Fig. 6). Disconnect electri-
cal connector.
(5) Remove 3 mounting bolts (Fig. 6).
(6) Remove APPS assembly from battery tray.
Fig. 1 CABLE/LEVER/THROTTLE LINKAGE COVER
1 - CABLE/LEVER/LINKAGE COVER
2 - PUSH UP LOWER TAB
3 - SCREWS/CLIPS (2)
4 - TAB PUSH HERE
Fig. 2 SERVO CABLE AT THROTTLE LEVER
1 - PINCH (2) TABS
2 - CABLE MOUNTING BRACKET
3 - PINCH TABS (2)
4 - OFF
5 - THROTTLE CABLE
6 - THROTTLE LEVER
7 - THROTTLE LEVER PIN
8 - OFF
9 - CONNECTOR
10 - SPEED CONTROL CABLE
DRFUEL INJECTION - DIESEL 14 - 69
ACCELERATOR PEDAL POSITION SENSOR (Continued)

INSTALLATION
Engine Mounted Sensor :
The APPS is serviced (replaced) as one assembly
including the lever, brackets and sensor. The APPS is
calibrated to its mounting bracket.
(1) Snap electrical connector into bottom of sensor.
(2) Position APPS assembly to engine and install 6
bolts. Tighten bolts to 24 N´m (18 ft. lbs.) torque.
(3) Connect wiring harness clip at bottom of
bracket.
(4) Refer to Group 21, Transmission for transmis-
sion control cable installation procedures.
(5) Install speed control cable into mounting
bracket. Be sure pinch tabs have secured cable.
(6) Install throttle cable into mounting bracket. Be
sure pinch tabs have secured cable.
(7) Connect throttle cable at lever (snaps on).
(8) Connect speed control cable to lever by pushing
cable connector rearward onto lever pin while hold-
ing lever forward.
(9) Install cable cover.
(10) Connect both negative battery cables to both
batteries.
(11) If necessary, use DRB IIItScan Tool to erase
any Diagnostic Trouble Codes (DTC's) from ECM.Battery Tray Mounted Sensor :
(1) Install Accelerator Pedal Position Sensor
(APPS) cable to accelerator pedal. Refer to Accelera-
tor Pedal Removal / Installation.
(2) Connect electrical connector to APPS.
(3) If necessary, connect cable to APPS lever ball
socket (snaps on).
(4) Snap APPS cable cover closed.
(5) Position APPS assembly to bottom of battery
tray and install 3 bolts. Refer to Torque Specifica-
tions.
(6) Install wheelhouse liner. Refer to Body.
(7) Perform the following procedure:
(a) Connect negative battery cables to both bat-
teries.
(b) Turn key switch ON, but do not crank
engine.
(c) Leave key switch ON for a minimum of 10
seconds. This will allow ECM to learn electrical
parameters.
(8) If necessary, use DRB IIItScan Tool to erase
any Diagnostic Trouble Codes (DTC's) from ECM.
CAMSHAFT POSITION
SENSOR
DESCRIPTION
The Camshaft Position Sensor (CMP) on the 5.9L
diesel engine is located below the fuel injection
pump. It is bolted to the back of the timing gear
housing.
OPERATION
The diesel Camshaft Position Sensor (CMP) con-
tains a hall effect device. A rotating target wheel
(tonewheel) for the CMP is located on the camshaft
gear. This hall effect device detects notches located
on the back side of the camshaft gear. As the cam-
shaft gear rotates, the notches pass the tip of the
CMP.
When the leading edge of the notch passes the tip
of the CMP, the following occurs: The interruption of
magnetic field causes the voltage to switch high
resulting in a signal of approximately 5 volts.
When the trailing edge of the notch passes the tip
of the CMP, the following occurs: The change of the
magnetic field causes the signal voltage to switch low
to 0 volts.
The CMP (Fig. 8) provides a signal to the Engine
Control Module (ECM) at all times when the engine
is running. The ECM uses the CMP information pri-
marily on engine start-up. Once the engine is run-
ning, the ECM uses the CMP as a backup sensor for
engine speed. The Crankshaft Position Sensor (CKP)
Fig. 7 APPS CABLE (OFF ENGINE MOUNTING)
1 - APPS LEVER
2 - BALL SOCKET
3 - SWING-DOWN DOOR
4 - CABLE CLIP
5 - CABLE
DRFUEL INJECTION - DIESEL 14 - 71
ACCELERATOR PEDAL POSITION SENSOR (Continued)

MAP SENSOR
DESCRIPTION
A combination, dual function Intake Manifold Air
Temperature Sensor/MAP Sensor is used. Refer to
Intake Air Temperature Sensor/MAP Sensor for infor-
mation.
THROTTLE CONTROL CABLE
REMOVAL
If Equipped With Engine Mounted Accelerator Pedal
Position Sensor
(1) Disconnect both negative battery cables at both
batteries.
(2) From inside vehicle, hold up accelerator pedal.
Remove plastic cable retainer and throttle cable core
wire from upper end of pedal arm (Fig. 32). The plas-
tic cable retainer snaps into pedal arm.
(3) From inside vehicle, remove cable clip (Fig. 32).
(4) Remove cable core wire at pedal arm.
(5) Remove cable housing from dash panel and
pull cable into engine compartment.
(6) Remove cable cover (Fig. 33). Cable cover is
attached with 2 Phillips screws, 2 plastic retention
clips and 2 push tabs (Fig. 33). Remove 2 Phillips
screws and carefully pry out 2 retention clips. After
clip removal, push rearward on front tab, and
upward on lower tab for cover removal.
(7) Using 2 screwdrivers, pry cable connector
socket from throttle lever ball (Fig. 34).Be very
careful not to bend throttle lever arm.
If Equipped With Battery Tray Mounted Accelerator Pedal
Position Sensor
The Throttle Control Cable connects the accelera-
tor pedal to the Accelerator Pedal Position Sensor
(APPS). A separate mechanical cable is not routed to
the throttle body.
CAUTION: Be careful not to damage or kink cable
core wire (within cable sheathing) while servicing
accelerator pedal, cables or APPS.
(1) Disconnect both negative battery cables at both
batteries.
(2) From inside vehicle, hold up accelerator pedal.
Remove plastic cable retainer and throttle cable core
wire from upper end of pedal arm (Fig. 35). The plas-
tic cable retainer snaps into pedal arm.
(3) Remove cable core wire at pedal arm.
(4) Remove APPS. Refer to (Diesel) Accelerator
Pedal Position Sensor (APPS) Removal / Installation.
(5) From inside vehicle, remove cable clip (Fig. 35).
Fig. 30 INTAKE/MAP SENSOR
1 - TOP OF INTAKE MANIFOLD
2 - IAT/MAP SENSOR
3 - ELEC. CONNECTOR
4 - MOUNTING BOLTS (2)
Fig. 31 SENSOR O-RING
1 - IAT/MAP SENSOR
2 - O-RING
DRFUEL INJECTION - DIESEL 14 - 83
INTAKE AIR TEMPERATURE SENSOR/MAP SENSOR (Continued)

NOTE: When servicing the steering wheel after
removing the old bolt a new bolt must be used
when installing.
NOTE: When servicing the coupler a new bolt must
be used when installing.
DIAGNOSIS AND TESTING - STEERING
COLUMN
If the vehicle is involved in a front end collision/the
air bag has deployed the column must be inspected.
This inspection will determine if the Column has col-
lapsed. Inspect the column mounting capsules visu-
ally and manually push and pull them to check for
separation or fractures. If capsules are fractured or
have moved the column MUST be replaced.
REMOVAL
WARNING: BEFORE SERVICING THE STEERING
COLUMN THE AIRBAG SYSTEM MUST BE DIS-
ARMED. REFER TO ELECTRICAL RESTRAINT SYS-
TEM FOR SERVICE PROCEDURES. FAILURE TO DO
SO MAY RESULT IN ACCIDENTAL DEPLOYMENT OF
THE AIRBAG AND POSSIBLE PERSONAL INJURY.CAUTION: All fasteners must be torqued to specifi-
cation to ensure proper operation of the steering
column.
(1) Position the front wheelsstraight ahead.
(2) Disconnect the negative (ground) cable from
the battery.
(3) Remove the two switches from the steering
wheel.
(4) Remove the airbag, (Refer to 8 - ELECTRICAL/
RESTRAINTS/DRIVER AIRBAG - REMOVAL).
(5) Remove the steering wheel with special tool
CJ98±1 or an appropriate steering wheel puller.
CAUTION: Ensure the puller bolts are fully engaged
into the steering wheel and not into the clock-
spring, before attempting to remove the wheel. Fail-
ure to do so may damage the steering wheel/
clockspring.
(6) Remove the steering column opening cover
(Refer to 23 - BODY/INSTRUMENT PANEL/STEER-
ING COLUMN OPENING COVER - REMOVAL).
(7) Remove the tilt lever.
(8) Remove the column shrouds (Fig. 2).
(9) Remove the clock spring, (Refer to 8 - ELEC-
TRICAL/RESTRAINTS/CLOCKSPRING -
REMOVAL).
(10) Disconnect the wiring harness to the column.
Fig. 1 STEERING COLUMN
1 - LOCK CYLINDER
2 - GEAR SHIFT LEVER
3 - MOUNTING HOLES
4 - STEERING COLUMN
5 - TILT LEVER
Fig. 2 UPPER & LOWER SHROUDS
1 - UPPER SHROUD
2 - LOWER SHROUD
DRCOLUMN 19 - 7
COLUMN (Continued)

(17) Remove the steering column assembly from
the vehicle. (Fig. 7)
INSTALLATION
WARNING: BEFORE SERVICING THE STEERING
COLUMN THE AIRBAG SYSTEM MUST BE DIS-
ARMED. REFER TO ELECTRICAL RESTRAINT SYS-
TEM FOR SERVICE PROCEDURES. FAILURE TO DO
SO MAY RESULT IN ACCIDENTAL DEPLOYMENT OF
THE AIRBAG AND POSSIBLE PERSONAL INJURY.
CAUTION: All fasteners must be torqued to specifi-
cation to ensure proper operation of the steering
column.
(1) Position the steering column on the dash panel
support and loosely install the mounting nuts.
(2) Firmly slide the steering column upward
against the studs in dash panel and hand tighten the
nuts.
(3) Install the steering shaft coupler on the steer-
ing shaft and loosely install anewbolt.
(4) Center steering column in dash opening and
tighten mounting nuts to 28 N´m (250 in. lbs.).
NOTE: Torque the upper left nut first then the lower
right nut. Then torque the lower left nut then the
upper right nut.
NOTE: A new bolt must be used for reinstallation.
(5) Tighten the coupler bolt to 57 N´m (42 ft. lbs.).(6) Install a new brake light switch (Refer to 8 -
ELECTRICAL/LAMPS/LIGHTING - EXTERIOR/
BRAKE LAMP SWITCH - REMOVAL).
(7) Install the shifter cable. (Refer to 21 - TRANS-
MISSION/TRANSAXLE/AUTOMATIC - 32RH/GEAR
SHIFT CABLE - INSTALLATION)
(8) Connect the wiring harness to the column.
(9) Install the SKIM module.
(10) Install the clockspring(Refer to 8 - ELECTRI-
CAL/RESTRAINTS/CLOCKSPRING - REMOVAL).
(11) Install the shrouds.
(12) Install the steering column opening cover
(Refer to 23 - BODY/INSTRUMENT PANEL/STEER-
ING COLUMN OPENING COVER - INSTALLA-
TION).
(13) Align the spline on the wheel hub to shaft.
(14) Then install the steering wheel and install a
newbolt. Tighten the bolt to 61 N´m (45 ft. lbs.).
(15) Install the airbag (Refer to 8 - ELECTRICAL/
RESTRAINTS/DRIVER AIRBAG - INSTALLATION).
(16) Install the two steering wheel switches.
(17) Install the tilt lever handle.
(18) Install the negative battery terminal.
(19) Test the operation of the horn, Electronic
PRNDL Indicator, lights and any other functions that
are steering column operated.
IGNITION SWITCH
DESCRIPTION
The ignition switch is located on the steering col-
umn. It is used as the main on/off switching device
for most electrical components. The mechanical key
cylinder is used to engage/disengage the electrical
ignition switch.
OPERATION
Vehicles equipped with an automatic trans-
mission and a steering column mounted shifter:
an interlock device is located within the shift cable.
This interlock device is used to lock the transmission
shifter in the PARK position when the key cylinder is
in any position and the brake pedal is not depressed.
DIAGNOSIS AND TESTING - IGNITION SWITCH
TEST AND REPAIR
If the key removal effort is excessive on a vehicle
with a automatic transmission first adjust the shift
linkage, (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - 46RE/GEAR SHIFT CABLE -
ADJUSTMENTS).
If the ignition switch effort is excessive remove the
ignition key cylinder from the steering column. (Refer
to 19 - STEERING/COLUMN/LOCK CYLINDER
Fig. 7 STEERING COLUMN
1 - Steering Wheel
2 - Key Cylinder
3 - Gear Shift Lever
4 - Steering Column
5 - Tilt Lever Cable
DRCOLUMN 19 - 9
COLUMN (Continued)

KEY CYLINDER
REMOVAL
The ignition key must be in the key cylinder for
cylinder removal.
(1) Disconnect negative cable from battery.
(2) Remove upper and lower covers (shrouds) from
steering column.
(3) Place shifter in PARK position.
(4) A retaining pin (Fig. 12) is located at side of
key cylinder assembly.
(a) Rotate key to RUN position.
(b) Press in on retaining pin while pulling key
cylinder from ignition switch (Fig. 13).
INSTALLATION
The ignition key must be in the key cylinder for
cylinder installation.
(1) Install the key cylinder into the housing using
care to align the end of the key cylinder with the
ignition switch.
(2) Push the key cylinder in until it clicks.
(3) Replace the upper and lower shrouds.
(4) Reconnect the battery.
GEAR SHIFT LEVER
REMOVAL
(1) Remove the kneeblocker. (Refer to 23 - BODY/
INSTRUMENT PANEL/KNEE BLOCKER -
REMOVAL).
(2) Remove the upper and lower column shroud.
(3) Remove and discard the brake light switch.
(4) Loosen the column bolts and lower the column
enough to allow clearance for the gear shift lever
removal.
(5) Disconnect the overdrive switch harness (if
equipped).
(6) Disconnect the shift cable from the shift lever.
(7) Remove the SKIM.
(8) Remove the gear shift lever mounting screws
and remove the lever. (Fig. 14)
(9) Remove the blocker pin from the inhibit link
slot (Fig. 14).
INSTALLATION
(1) Install the lever assembly using care to install
the pin in the blocker to slider slot (Fig. 15) and
install the mounting screws and tighten to 12 N´m
(105 in. lbs.).
Fig. 12 KEY CYLINDER
1 - KEY
2 - KEY CYLINDER
3 - RETAINING PIN HOLE
Fig. 13 KEY CYLINDER
1 - KEY CYLINDER
2 - PUNCH
Fig. 14 GEAR SHIFT LEVER
1 - PARK INHIBIT BLOCKER SPRING
2 - GEAR SHIFT LEVER
19 - 12 COLUMNDR

(2) Cycle the key from ACC to RUN and ensure
that the blocker does not stick or bind.
(3) Turn the key to the OFF position and ensure
that the shifter will not pull from the PARK position.
(4) Connect the over drive switch harness (if
equipped).
NOTE: Route and tie off harness to original loca-
tion.
(5) Connect the shift cable to the lever.
(6) Ensure the gear shift lever and transmission
are in the PARK position and snap the cable adjust
clip in place.
(7) Install a new brake light switch (Refer to 8 -
ELECTRICAL/LAMPS/LIGHTING - EXTERIOR/
BRAKE LAMP SWITCH - INSTALLATION).
(8) Install the SKIM and halo.
(9) Install the upper and lower column shroud.
(10) Install the column back into place and
tighten.
(11) Install the kneeblocker. (Refer to 23 - BODY/
INSTRUMENT PANEL/KNEE BLOCKER - INSTAL-
LATION).
UPPER STEERING COUPLING
REMOVAL
(1) Disconnect the negative battery cable.
NOTE: The steering column on vehicles with an
automatic transmission may not be equipped with
an internal locking shaft that allows the ignition key
cylinder to be locked with the key. Alternative meth-
ods of locking the steering wheel for service will
have to be used.(2) Lock the steering wheel with the tire in the
straight position.
(3) Remove and discard the lower pinch bolt.
(4) Lower the steering coupler shaft from the col-
umn.
(5) Remove the upper steering coupling shaft seal
by pushing in the four tags securing it to the panel
(Fig. 16).
(6) Remove and discard the lower coupler pinch
bolt from the lower steering coupling shaft (Fig. 17).
(7) Remove the upper steering coupling shaft from
the vehicle (Fig. 17).
INSTALLATION
(1) Install the upper steering coupling shaft to the
vehicle (Fig. 17).
Fig. 15 GEAR SHIFT LEVER SPRING
1 - BLOCKER TO INHIBIT LINK SLOT
2 - GEAR SHIFT LEVER
Fig. 16 RELEASE TANGS
1 - RELEASE TANGS (4)
2 - UPPER STEERING COUPLER SHAFT
Fig. 17 UPPER STEERING COUPLER SHAFT
1 - LOWER STEERING COUPLER
2 - RELEASE TANGS (4)
3 - UPPER STEERING COUPLER SHAFT
DRCOLUMN 19 - 13
GEAR SHIFT LEVER (Continued)