ESP DODGE RAM 2001 Service Manual PDF

²If the actual speed is not within 20 mph of the
set speedThe previous disengagement conditions are
programmed for added safety.
Once the speed control has been disengaged,
depressing the ACCEL switch restores the vehicle to
the target speed that was stored in the ECM's RAM.
NOTE: Depressing the OFF switch will erase the set
speed stored in the ECM's RAM.
If, while the speed control is engaged, the driver
wishes to increase vehicle speed, the ECM is pro-
grammed for an acceleration feature. With the
ACCEL switch held closed, the vehicle accelerates
slowly to the desired speed. The new target speed is
stored in the ECM's RAM when the ACCEL switch is
released. The ECM also has a9tap-up9feature in
which vehicle speed increases at a rate of approxi-
mately 2 mph for each momentary switch activation
of the ACCEL switch.
The ECM also provides a means to decelerate with-
out disengaging speed control. To decelerate from an
existing recorded target speed, depress and hold the
COAST switch until the desired speed is reached.
Then release the switch. The ON, OFF switch oper-
ates two components: the ECM's ON, OFF input, and
the battery voltage to the brake switch, which powers
the speed control servo.
REMOVAL
WARNING: BEFORE BEGINNING ANY AIRBAG SYS-
TEM COMPONENT REMOVAL OR INSTALLATION,
REMOVE AND ISOLATE THE NEGATIVE (-)
CABLE(S) FROM THE BATTERY. THIS IS THE ONLY
SURE WAY TO DISABLE THE AIRBAG SYSTEM.
THEN WAIT TWO MINUTES FOR SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE FURTHER SYSTEM
SERVICE. FAILURE TO DO THIS COULD RESULT IN
ACCIDENTAL AIRBAG DEPLOYMENT AND POSSI-
BLE INJURY.
(1) Disconnect and isolate negative battery
cable(s).
(2) Remove airbag module. Refer to 8, Restraint
Systems for procedures.
(3) Remove switch-to-steering wheel mounting
screws (Fig. 20).
(4) Remove switch.
(5) Remove electrical connector at switch.
INSTALLATION
(1) Install electrical connector to switch.
(2) Install switch and mounting screws.
(3) Tighten screws to 3 N´m (26 in. lbs. +/± 2 in.
lbs.) torque.(4) Install airbag module. Refer to 8, Restraint
Systems for procedures.
(5) Connect negative battery cable(s).
VACUUM RESERVOIR
DESCRIPTION
Gasoline Powered Engines :A vacuum reservoir
is used to supply the vacuum needed to maintain
proper speed control operation when engine vacuum
drops, such as in climbing a grade while driving. A
one-way check valve is used in the vacuum line
between the reservoir and the vacuum source. This
check valve is used to trap engine vacuum in the res-
ervoir. On certain vehicle applications, this reservoir
is shared with the heating/air-conditioning system.
The vacuum reservoir cannot be repaired and must
be replaced if faulty.
Diesel Powered Engines With Auto. Trans. :A
vacuum reservoir is not used if equipped with a die-
sel powered engine. Instead, an engine driven pump
(vacuum pump) is used to supply vacuum for speed
control operation. This vacuum pump is used with
the diesel engine only if it is equipped with an auto-
matic transmission. Refer to Vacuum Pump in 9,
Engines for information.
REMOVAL
The vacuum reservoir is located under the plastic
cowel plenum cover at lower base of windshield. The
vacuum reservoir is not used if equipped with a die-
sel engine.
Fig. 20 Speed Control Switches
1 - MOUNTING SCREWS (2)
2 - SPEED CONTROL SWITCHES (2)
BR/BESPEED CONTROL 8P - 13
SWITCH (Continued)

VEHICLE THEFT SECURITY
TABLE OF CONTENTS
page page
VEHICLE THEFT SECURITY
DESCRIPTION............................1
OPERATION.............................2
DIAGNOSIS AND TESTING..................3
VEHICLE THEFT SECURITY SYSTEM........3VTSS INDICATOR
DESCRIPTION............................3
OPERATION.............................3
DIAGNOSIS AND TESTING..................3
VTSS INDICATOR.......................3
VEHICLE THEFT SECURITY
DESCRIPTION
The Vehicle Theft Security System (VTSS) is an
available factory-installed option on this model when
it is also equipped with the high-line or premium
Central Timer Module (CTM). The VTSS is designed
to provide perimeter protection against unauthorized
use or tampering by monitoring the vehicle doors and
the ignition system. If unauthorized vehicle use or
tampering is detected, the system responds by puls-
ing the horn, flashing the headlamps, and preventing
the engine from operating.
The VTSS includes the following major compo-
nents, which are described in further detail else-
where in this service manual:
²Central Timer Module- The high-line or pre-
mium Central Timer Module (CTM) is located under
the driver side end of the instrument panel, inboard
of the instrument panel steering column opening.
The high-line or premium CTM contains a micropro-
cessor and software that allow it to provide many
electronic functions and features not available with
base version of the CTM, including the VTSS. The
CTM provides all of the proper VTSS features and
outputs based upon the monitored inputs. The CTM
circuitry monitors hard wired switch inputs, as well
as message inputs received from other vehicle elec-
tronic modules over the Chrysler Collision Detection
(CCD) data bus network. (Refer to 8 - ELECTRICAL/
ELECTRONIC CONTROL MODULES/BODY CON-
TROL/CENTRAL TIMER MODULE -
DESCRIPTION).
²Door Ajar Switch- A door ajar switch is
located on the hinge pillar of each front door in the
vehicle. These switches provide an input to the VTSS
indicating whether the door is opened or closed.
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
INTERIOR/DOOR AJAR SWITCH - DESCRIPTION).
²Door Cylinder Lock Switch- A door cylinder
lock switch is located on the back of each front door
lock cylinder. This switch provides an input to theVTSS indicating whether the system should remain
armed or be disarmed. (Refer to 8 - ELECTRICAL/
POWER LOCKS/DOOR CYLINDER LOCK SWITCH
- DESCRIPTION).
²Horn Relay- The horn relay is located in the
Power Distribution Center (PDC) in the engine com-
partment near the battery. The horn relay is nor-
mally activated by the horn switch to control the
sounding of the vehicle horn or horns. However, it
can also be activated by an output of the Central
Timer Module (CTM) to provide an audible indication
that unauthorized vehicle use or tampering has been
detected. (Refer to 8 - ELECTRICAL/HORN/HORN
RELAY - DESCRIPTION).
²Headlamp Relay- The headlamp relay (also
known as the security relay) is located in the Power
Distribution Center (PDC) in the engine compart-
ment near the battery. The headlamp relay is nor-
mally activated by the Central Timer Module (CTM)
based upon inputs from the Remote Keyless Entry
(RKE) panic mode feature. However, it can also be
activated by an output of the CTM to flash the head-
lamp low beams to provide a highly visible indication
that unauthorized vehicle use or tampering has been
detected. (Refer to 8 - ELECTRICAL/LAMPS/LIGHT-
ING - EXTERIOR/HEADLAMP RELAY - DESCRIP-
TION).
²VTSS Indicator- A red Light Emitting Diode
(LED) located on the lower surface of the overhead
console near the windshield is illuminated by an out-
put of the Central Timer Module (CTM) to indicate
the status of the VTSS. This LED is integral to the
electronic circuit board for the Compass Mini-Trip
Computer (CMTC). (Refer to 8 - ELECTRICAL/
OVERHEAD CONSOLE/COMPASS/MINI-TRIP
COMPUTER - DESCRIPTION).
The engine no-run feature of the VTSS relies upon
communication between the high-line or premium
CTM and the Powertrain Control Module (PCM) over
the Chrysler Collision Detection (CCD) data bus net-
work.
Hard wired circuitry connects many of the VTSS
components to each other through the electrical sys-
BR/BEVEHICLE THEFT SECURITY 8Q - 1

er-up mode will also apply if the battery goes dead
while the system is armed, and battery jump-starting
is attempted. The engine no-run feature will prevent
the engine from starting until the alarm system has
been actively or passively disarmed. The VTSS will
be armed until the technician or vehicle operator has
actively or passively disarmed the alarm system. If
the VTSS is in the disarmed mode prior to a battery
disconnect or failure, it will remain disarmed after
the battery is reconnected or replaced, or if jump-
starting is attempted.
TAMPER ALERT
The VTSS tamper alert feature will sound the horn
three times upon disarming, if the alarm was trig-
gered and has since timed-out (about fifteen min-
utes). This feature alerts the vehicle operator that
the VTSS alarm was activated while the vehicle was
unattended.
DIAGNOSIS AND TESTING - VEHICLE THEFT
SECURITY SYSTEM
The VTSS-related hard wired inputs to and out-
puts from the high-line or premium Central Timer
Module (CTM) may be diagnosed and tested using
conventional diagnostic tools and procedures. Refer
to the appropriate wiring information. The wiring
information includes wiring diagrams, proper wire
and connector repair procedures, further details on
wire harness routing and retention, as well as pin-
out and location views for the various wire harness
connectors, splices and grounds.
However, conventional diagnostic methods may not
prove conclusive in the diagnosis of the CTM, the
Powertrain Control Module (PCM), or the Chrysler
Collision Detection (CCD) data bus network. In order
to obtain conclusive testing of the VTSS, the CTM,
the PCM, and the CCD data bus network must also
be checked. The most reliable, efficient, and accurate
means to diagnose the VTSS requires the use of a
DRBIIIž scan tool. Refer to the appropriate diagnos-
tic information. The DRBIIIž scan tool can provide
confirmation that the CCD data bus network is func-
tional, that all of the electronic modules are sending
and receiving the proper messages over the CCD
data bus, and that these modules are receiving the
proper hard wired inputs and responding with the
proper hard wired outputs needed to perform their
functions. See the ªVehicle Theft Security Systemº
menu item on the DRBIIIž scan tool.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
VTSS INDICATOR
DESCRIPTION
The Vehicle Theft Security System (VTSS) indica-
tor consists of a red Light-Emitting Diode (LED)
located on the electronic circuit board of the Compass
Mini-Trip Computer (CMTC) within the overhead
console. The LED extends through a hole in the
CMTC lens located near the forward end of the over-
head console housing near the windshield.
The VTSS indicator cannot be adjusted or repaired
and, if faulty or damaged, the entire CMTC unit
must be replaced. (Refer to 8 - ELECTRICAL/OVER-
HEAD CONSOLE/COMPASS/MINI-TRIP COM-
PUTER - DESCRIPTION).
OPERATION
The Vehicle Theft Security System (VTSS) indica-
tor gives a visible indication of the VTSS arming sta-
tus. One side of Light-Emitting Diode (LED) in the
VTSS indicator is connected to battery current
through a fused B(+) circuit and a fuse in the Junc-
tion Block (JB), so the indicator remains functional
regardless of the ignition switch position. The other
side of the LED is hard wired to the Central Timer
Module (CTM), which controls the operation of the
VTSS indicator by pulling this side of the LED cir-
cuit to ground. When the VTSS arming is in
progress, the CTM will flash the LED rapidly on and
off for about fifteen seconds. When the VTSS has
been successfully armed, the CTM will flash the LED
on and off continually at a much slower rate until
the VTSS has been disarmed. The VTSS indicator
can be diagnosed using conventional diagnostic tools
and methods.
DIAGNOSIS AND TESTING - VTSS INDICATOR
The diagnosis found here addresses an inoperative
Vehicle Theft Security System (VTSS) indicator con-
dition. If the problem being diagnosed is related to
indicator accuracy, be certain to confirm that the
problem is with the indicator and not with an inop-
erative VTSS. (Refer to 8 - ELECTRICAL/VEHICLE
THEFT SECURITY SYSTEM- DIAGNOSIS AND
BR/BEVEHICLE THEFT SECURITY 8Q - 3
VEHICLE THEFT SECURITY (Continued)

activates the washer pump/motor, which dispenses
washer fluid onto the windshield glass through the
washer nozzles.
When the ignition switch is in the Accessory or On
positions, battery current from a fuse in the Junction
Block (JB) is provided through a fused ignition
switch output (run-acc) circuit to the wiper motor
park switch, the wiper relay, and the multi-function
switch. The internal circuitry of the multi-function
switch provides a direct hard wired battery current
output to the low speed or high speed brushes of the
wiper motor when the Lo or Hi switch setting is
selected, which causes the wipers to cycle at the
selected speed. The intermittent wipe, and wipe-af-
ter-wash features of the wiper and washer system
are provided by the electronic intermittent wipe logic
circuit within the Central Timer Module (CTM). In
order to provide the intermittent wipe feature, the
CTM monitors the wiper switch state and the wiper
motor park switch state. In order to provide the
wipe-after-wash feature, the CTM monitors both the
washer switch state and the wiper motor park switch
state. When a Delay position is selected with the
multi-function switch control knob, the CTM logic cir-
cuit responds by calculating the correct delay inter-
val. The CTM then energizes the wiper relay by
pulling the relay control coil to ground. The ener-
gized wiper relay directs battery current through the
normally open contact of the relay back through the
internal circuitry of the multi-function switch to the
low speed brush of the wiper motor. The CTM moni-
tors the wiper motor operation through the wiper
park switch sense circuit, which allows the CTM to
determine the proper timing to begin the next wiper
blade sweep. The normal delay intervals are driver
adjustable from about one-half second to about eigh-
teen seconds.
The high-line and premium CTM also provides a
speed sensitive intermittent wipe feature. By moni-
toring vehicle speed messages received from the Pow-
ertrain Control Module (PCM) over the Chrysler
Collision Detection (CCD) data bus network, the
high-line or premium CTM is able to adjust the delay
intervals to compensate for vehicle speed. Above
about sixteen kilometers-per-hour (ten miles-per-
hour) the delay is driver adjustable from about one-
half second to about eighteen seconds. Below about
sixteen kilometers-per-hour (ten miles-per-hour) the
delay times are doubled by the CTM, from about one
second to about thirty-six seconds.
When the Off position of the multi-function switch
wiper control knob is selected, one of two events is
possible. The event that will occur depends upon the
position of the wiper blades on the windshield at the
moment that the Off position is selected. If the wiper
blades are in the down position on the windshieldwhen the Off position is selected, the park switch
that is integral to the wiper motor is closed to ground
and the wiper motor ceases to operate. If the wiper
blades are not in the down position on the windshield
at the moment the Off position is selected, the park
switch is closed to battery current through a fused
ignition switch output (run-acc) circuit. The park
switch sense circuit directs this battery current to
the low speed brush of the wiper motor through the
normally closed contact of the wiper relay and the
internal Off position circuitry of the multi-function
switch. This causes the wiper motor to continue run-
ning until the wiper blades are in the down position
on the windshield and the park switch is again
closed to ground.
When the Wash position of the multi-function
switch is selected, the Wash position circuitry within
the switch directs battery current to the washer
pump/motor. The CTM monitors the washer switch
state through a washer switch sense input. When the
washer switch is closed with the wiper system turned
Off, the CTM operates the wiper motor through the
wiper relay in the same manner as it does to provide
the Delay mode operation. After the state of the
washer switch changes to open, the CTM monitors
the wiper motor through the wiper park switch sense
circuit, which allows the CTM to monitor the number
of wiper blade sweeps.
Proper testing of the CTM, the PCM, or the CCD
data bus vehicle speed messages requires a DRBIIIt
scan tool. Refer to the appropriate diagnostic infor-
mation. Refer to the owner's manual in the vehicle
glove box for more information on the features and
operation of the wiper and washer system.
DIAGNOSIS AND TESTING - WIPER &
WASHER SYSTEM
WIPER SYSTEM
The diagnosis found here addresses an electrically
inoperative wiper system. If the wiper motor oper-
ates, but the wipers do not move on the windshield,
replace the faulty wiper module. If the wipers oper-
ate, but chatter, lift, or do not clear the glass, clean
and inspect the wiper system components as
required. (Refer to 8 - ELECTRICAL/WIPERS/
WASHERS - INSPECTION) and (Refer to 8 - ELEC-
TRICAL/WIPERS/WASHERS - CLEANING). Refer to
the appropriate wiring information. The wiring infor-
mation includes wiring diagrams, proper wire and
connector repair procedures, details of wire harness
routing and retention, connector pin-out information
and location views for the various wire harness con-
nectors, splices and grounds.
The following tests will help to diagnose the hard
wired components and circuits of the wiper system.
BR/BEWIPERS/WASHERS 8R - 3
WIPERS/WASHERS (Continued)

TERMINOLOGY
This is a list of terms and definitions used in the
wiring diagrams.
LHD .................Left Hand Drive Vehicles
RHD................Right Hand Drive Vehicles
ATX . . Automatic Transmissions-Front Wheel Drive
MTX....Manual Transmissions-Front Wheel Drive
AT ....Automatic Transmissions-Rear Wheel Drive
MT .....Manual Transmissions-Rear Wheel Drive
SOHC...........Single Over Head Cam Engine
DOHC..........Double Over Head Cam Engine
Built-Up-Export........ Vehicles Built For Sale In
Markets Other Than North America
Except-Built-Up-Export . . Vehicles Built For Sale In
North America
WARNINGS - GENERAL
WARNINGSprovide information to prevent per-
sonal injury and vehicle damage. Below is a list of
general warnings that should be followed any time a
vehicle is being serviced.
WARNING:: ALWAYS WEAR SAFETY GLASSES FOR
EYE PROTECTION.
WARNING: USE SAFETY STANDS ANYTIME A PRO-
CEDURE REQUIRES BEING UNDER A VEHICLE.
WARNING: BE SURE THAT THE IGNITION SWITCH
ALWAYS IS IN THE OFF POSITION, UNLESS THE
PROCEDURE REQUIRES IT TO BE ON.
WARNING: SET THE PARKING BRAKE WHEN
WORKING ON ANY VEHICLE. AN AUTOMATIC
TRANSMISSION SHOULD BE IN PARK. A MANUAL
TRANSMISSION SHOULD BE IN NEUTRAL.
WARNING: OPERATE THE ENGINE ONLY IN A
WELL-VENTILATED AREA.
WARNING: KEEP AWAY FROM MOVING PARTS
WHEN THE ENGINE IS RUNNING, ESPECIALLY THE
FAN AND BELTS.
WARNING: TO PREVENT SERIOUS BURNS, AVOID
CONTACT WITH HOT PARTS SUCH AS THE RADIA-
TOR, EXHAUST MANIFOLD(S), TAIL PIPE, CATA-
LYTIC CONVERTER AND MUFFLER.WARNING: DO NOT ALLOW FLAME OR SPARKS
NEAR THE BATTERY. GASES ARE ALWAYS
PRESENT IN AND AROUND THE BATTERY.
WARNING: ALWAYS REMOVE RINGS, WATCHES,
LOOSE HANGING JEWELRY AND LOOSE CLOTH-
ING.
DIAGNOSIS AND TESTING - WIRING HARNESS
TROUBLESHOOTING TOOLS
When diagnosing a problem in an electrical circuit
there are several common tools necessary. These tools
are listed and explained below.
²Jumper Wire - This is a test wire used to con-
nect two points of a circuit. It can be used to bypass
an open in a circuit.
WARNING: NEVER USE A JUMPER WIRE ACROSS
A LOAD, SUCH AS A MOTOR, CONNECTED
BETWEEN A BATTERY FEED AND GROUND.
²Voltmeter - Used to check for voltage on a cir-
cuit. Always connect the black lead to a known good
ground and the red lead to the positive side of the
circuit.
CAUTION: Most of the electrical components used
in today's vehicles are Solid State. When checking
voltages in these circuits, use a meter with a 10 -
megohm or greater impedance rating.
²Ohmmeter - Used to check the resistance
between two points of a circuit. Low or no resistance
in a circuit means good continuity.
CAUTION: Most of the electrical components used
in today's vehicles are Solid State. When checking
resistance in these circuits use a meter with a 10 -
megohm or greater impedance rating. In addition,
make sure the power is disconnected from the cir-
cuit. Circuits that are powered up by the vehicle's
electrical system can cause damage to the equip-
ment and provide false readings.
²Probing Tools - These tools are used for probing
terminals in connectors (Fig. 4)Select the proper size
tool from Special Tool Package 6807, and insert it
into the terminal being tested. Use the other end of
the tool to insert the meter probe.
BR/BE8W-01 WIRING DIAGRAM INFORMATION 8W - 01 - 5
WIRING DIAGRAM INFORMATION (Continued)

(8) Turn crankshaft and camshaft to line up with
keyway location in crankshaft sprocket and in cam-
shaft sprocket.
(9) Lift sprockets and chain (keep sprockets tight
against the chain in position as described).
(10) Slide both sprockets evenly over their respec-
tive shafts and use a straightedge to check alignment
of timing marks (Fig. 22).
(11) Install the camshaft bolt/cup washer. Tighten
bolt to 68 N´m (50 ft. lbs.) torque.
(12) Measure camshaft end play (Fig. 23). (Refer to
9 - ENGINE - SPECIFICATIONS) for proper clear-
ance. If not within limits, install a new timing chain
tensioner.
(13) Each tappet reused must be installed in the
same position at which it was removed.When cam-
shaft is replaced, all of the tappets must be
replaced.Install hydraulic tappets (Refer to 9 -
ENGINE/ENGINE BLOCK/HYDRAULIC LIFTERS
(CAM IN BLOCK) - INSTALLATION).
(14) Install timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(15) Install intake manifold (Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - INSTALLA-
TION).
(16) Install distributor.
(17) Install cylinder head covers (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(18) Install radiator (Refer to 7 - COOLING/EN-
GINE/RADIATOR - INSTALLATION).
(19) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(20) Connect battery negative cable.
(21) Start engine and check for leaks.
CONNECTING ROD BEARINGS
STANDARD PROCEDURE-CONNECTING ROD
BEARING FITTING
Fit all rods on a bank until completed. DO NOT
alternate from one bank to another, because connect-
ing rods and pistons are not interchangeable from
one bank to another.
The bearing caps are not interchangeable and
should be marked at removal to ensure correct
assembly.
Each bearing cap has a small V-groove across the
parting face. When installing the lower bearing shell,
be certain that the V-groove in the shell is in line
with the V-groove in the cap. This provides lubrica-
tion of the cylinder wall in the opposite bank.The bearing shells must be installed so that the
tangs are in the machined grooves in the rods and
caps.
Limits of taper or out-of-round on any crankshaft
journals should be held to 0.025 mm (0.001 in.).
Bearings are available in 0.025 mm (0.001 in.), 0.051
mm (0.002 in.), 0.076 mm (0.003 in.), 0.254 mm
(0.010 in.) and 0.305 mm (0.012 in.) undersize.
Install the bearings in pairs. DO NOT use a new
bearing half with an old bearing half. DO NOT
file the rods or bearing caps.
CRANKSHAFT
DESCRIPTION
The crankshaft (Fig. 24) is of a forged steel splayed
type design, with four main bearing journals.The
crankshaft is located at the bottom of the engine
block and is held in place with four main bearing
caps.
OPERATION
The crankshaft transfers force generated by com-
bustion within the cylinder bores to the flywheel or
flexplate.
REMOVAL
(1) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(2) Remove the oil pump (Refer to 9 - ENGINE/
LUBRICATION/OIL PUMP - REMOVAL).
(3) Identify bearing caps before removal. Remove
bearing caps and bearings one at a time.
(4) Lift the crankshaft out of the block.
Fig. 24 CrankshaftÐ3.9L Engine
BR/BEENGINE 3.9L 9 - 31
CAMSHAFT & BEARINGS (IN BLOCK) (Continued)

HYDRAULIC LIFTERS (CAM IN
BLOCK)
DIAGNOSIS AND TESTINGÐHYDRAULIC
TAPPETS
Before disassembling any part of the engine to cor-
rect tappet noise, check the oil pressure. If vehicle
has no oil pressure gauge, install a reliable gauge at
the pressure sending-unit. The pressure should be
between 207-552 kPa (30-80 psi) at 3,000 RPM.
Check the oil level after the engine reaches normal
operating temperature. Allow 5 minutes to stabilize
oil level, check dipstick. The oil level in the pan
should never be above the FULL mark or below the
ADD OIL mark on dipstick. Either of these two con-
ditions could be responsible for noisy tappets.
OIL LEVEL
HIGH
If oil level is above the FULL mark, it is possible
for the connecting rods to dip into the oil. With the
engine running, this condition could create foam in
the oil pan. Foam in oil pan would be fed to the
hydraulic tappets by the oil pump causing them to
lose length and allow valves to seat noisily.
LOW
Low oil level may allow oil pump to take in air.
When air is fed to the tappets, they lose length,
which allows valves to seat noisily. Any leaks on
intake side of oil pump through which air can be
drawn will create the same tappet action. Check the
lubrication system from the intake strainer to the
pump cover, including the relief valve retainer cap.
When tappet noise is due to aeration, it may be
intermittent or constant, and usually more than one
tappet will be noisy. When oil level and leaks have
been corrected, operate the engine at fast idle. Run
engine for a sufficient time to allow all of the air
inside the tappets to be bled out.
TAPPET NOISE DIAGNOSIS
(1) To determine source of tappet noise, operate
engine at idle with cylinder head covers removed.
(2) Feel each valve spring or rocker arm to detect
noisy tappet. The noisy tappet will cause the affected
spring and/or rocker arm to vibrate or feel rough in
operation.
NOTE: Worn valve guides or cocked springs are
sometimes mistaken for noisy tappets. If such is
the case, noise may be dampened by applying side
thrust on the valve spring. If noise is not apprecia-
bly reduced, it can be assumed the noise is in thetappet. Inspect the rocker arm push rod sockets
and push rod ends for wear.
(3) Valve tappet noise ranges from light noise to a
heavy click. A light noise is usually caused by exces-
sive leak-down around the unit plunger, or by the
plunger partially sticking in the tappet body cylinder.
The tappet should be replaced. A heavy click is
caused by a tappet check valve not seating, or by for-
eign particles wedged between the plunger and the
tappet body. This will cause the plunger to stick in
the down position. This heavy click will be accompa-
nied by excessive clearance between the valve stem
and rocker arm as valve closes. In either case, tappet
assembly should be removed for inspection and clean-
ing.
(4) The valve train generates a noise very much
like a light tappet noise during normal operation.
Care must be taken to ensure that tappets are mak-
ing the noise. If more than one tappet seems to be
noisy, it's probably not the tappets.
LEAK-DOWN TEST
After cleaning and inspection, test each tappet for
specified leak-down rate tolerance to ensure zero-lash
operation (Fig. 38).
Swing the weighted arm of the hydraulic valve tap-
pet tester away from the ram of the Universal Leak-
Down Tester.
(1) Place a 7.925-7.950 mm (0.312-0.313 inch)
diameter ball bearing on the plunger cap of the tap-
pet.
(2) Lift the ram and position the tappet (with the
ball bearing) inside the tester cup.
(3) Lower the ram, then adjust the nose of the ram
until it contacts the ball bearing. DO NOT tighten
the hex nut on the ram.
(4) Fill the tester cup with hydraulic valve tappet
test oil until the tappet is completely submerged.
(5) Swing the weighted arm onto the push rod and
pump the tappet plunger up and down to remove air.
When the air bubbles cease, swing the weighted arm
away and allow the plunger to rise to the normal
position.
(6) Adjust the nose of the ram to align the pointer
with the SET mark on the scale of the tester and
tighten the hex nut.
(7) Slowly swing the weighted arm onto the push
rod.
(8) Rotate the cup by turning the handle at the
base of the tester clockwise one revolution every 2
seconds.
(9) Observe the leak-down time interval from the
instant the pointer aligns with the START mark on
the scale until the pointer aligns with the 0.125
mark. A normally functioning tappet will require
9 - 38 ENGINE 3.9LBR/BE

(3) Using the transmission jack, lower the trans-
mission and support cushion onto the crossmember
(Fig. 49).
(4) Install the support cushion bolts and tighten to
41 N´m (30 ft. lbs.) torque.
(5) Remove the transmission jack.
(6) Lower the vehicle.
LUBRICATION
DESCRIPTION
A gear-type positive displacement pump (Fig. 50)is
mounted at the underside of the rear main bearing
cap. The pump uses a pick-up tube and screen
assembly to gather engine oil from the oil pan.
OPERATION
The pump draws oil through the screen and inlet
tube from the sump at the rear of the oil pan. The oil
is driven between the drive and idler gears and
pump body, then forced through the outlet to the
block. An oil gallery in the block channels the oil to
the inlet side of the full flow oil filter. After passing
through the filter element, the oil passes from the
center outlet of the filter through an oil gallery that
channels the oil up to the main gallery, which
extends the entire length on the right side of the
block. The oil then goes down to the No. 1 main bear-
ing, back up to the left side of the block, and into the
oil gallery on the left side of the engine.
Galleries extend downward from the main oil gal-
lery to the upper shell of each main bearing. The
crankshaft is drilled internally to pass oil from the
main bearing journals to the connecting rod journals.
Each connecting rod bearing has half a hole in it, oil
passes through the hole when the rods rotate and the
hole lines up, oil is then thrown off as the rod
rotates. This oil throwoff lubricates the camshaft
lobes, distributor drive gear, cylinder walls, and pis-
ton pins.The hydraulic valve tappets receive oil directly
from the main oil gallery. The camshaft bearings
receive oil from the main bearing galleries. The front
camshaft bearing journal passes oil through the cam-
shaft sprocket to the timing chain. Oil drains back to
the oil pan under the No. 1 main bearing cap.
The oil supply for the rocker arms and bridged
pivot assemblies is provided by the hydraulic valve
tappets, which pass oil through hollow push rods to a
hole in the corresponding rocker arm. Oil from the
rocker arm lubricates the valve train components.
The oil then passes down through the push rod guide
holes and the oil drain-back passages in the cylinder
head, past the valve tappet area, and then returns to
the oil pan (Fig. 51).
Fig. 50 Positive Displacement Oil PumpÐTypical
1 - INNER ROTOR AND SHAFT
2 - BODY
3 - DISTRIBUTOR DRIVESHAFT (REFERENCE)
4 - COTTER PIN
5 - RETAINER CAP
6 - SPRING
7 - RELIEF VALVE
8 - LARGE CHAMFERED EDGE
9 - BOLT
10 - COVER
11 - OUTER ROTOR
BR/BEENGINE 3.9L 9 - 45
REAR MOUNT (Continued)

INSPECTIONÐMEASURING TIMING CHAIN
STRETCH
NOTE: Timing chain tensioner must be removed for
this operation.
(1) Place a scale next to the timing chain so that
any movement of the chain can be measured.
(2) Place a torque wrench and socket over cam-
shaft sprocket attaching bolt. Apply torque in the
direction of crankshaft rotation to take up slack; 41
N´m (30 ft. lbs.) torque with cylinder head installed
or 20 N´m (15 ft. lbs.) torque with cylinder head
removed. With torque applied to the camshaft
sprocket bolt, crankshaft should not be permitted to
move. It may be necessary to block the crankshaft to
prevent rotation.
(3) Hold a scale with dimensional reading even
with the edge of a chain link. With cylinder heads
installed, apply 14 N´m (30 ft. lbs.) torque in the
reverse direction. With the cylinder heads removed,
apply 20 N´m (15 ft. lbs.) torque in the reverse direc-
tion. Note the amount of chain movement (Fig. 76).
(4) Install a new timing chain, if its movement
exceeds 3.175 mm (1/8 inch).
INSTALLATION
(1) If tensioner assembly is being replaced, install
tensioner and mounting bolts. Torque bolts to 24 N´m
(210 in. lbs.).
(2) Place both camshaft sprocket and crankshaft
sprocket on the bench with timing marks on an exact
imaginary center line through both camshaft and
crankshaft bores.
(3) Place timing chain around both sprockets.
(4) Lift sprockets and chain (keep sprockets tight
against the chain in position as described).(5) Slide both sprockets evenly over their respec-
tive shafts and verify alignment of timing marks
(Fig. 77) with a straight-edge if necessary.
(6) Install the camshaft bolt. Tighten the bolt to 68
N´m (50 ft. lbs.) torque.
(7)Remove tensioner pin.Again, verify align-
ment of timing marks.
(8) Install timing cover (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT / CHAIN COVER(S)
- INSTALLATION).
(9) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(10) Connect battery negative cable.
(11) Start engine and check for oil and coolant
leaks.
Fig. 76 Measuring Timing Chain Wear and Stretch
1 - TORQUE WRENCH
2 - 3.175 MM
(0.125 IN.)
Fig. 77 Alignment of Timing Marks
1 - TIMING MARKS
9 - 58 ENGINE 3.9LBR/BE
TIMING BELT/CHAIN AND SPROCKETS (Continued)

(4) Install the intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSTALLATION).
(5) Install the distributor (Refer to 8 - ELECTRI-
CAL/IGNITION CONTROL/DISTRIBUTOR -
INSTALLATION).
HYDRAULIC LIFTERS (CAM IN
BLOCK)
DIAGNOSIS AND TESTINGÐHYDRAULIC
TAPPETS
Before disassembling any part of the engine to cor-
rect tappet noise, check the oil pressure. If vehicle
has no oil pressure gauge, install a reliable gauge at
the pressure sending-unit. The pressure should be
between 207-552 kPa (30-80 psi) at 3,000 RPM.
Check the oil level after the engine reaches normal
operating temperature. Allow 5 minutes to stabilize
oil level, check dipstick. The oil level in the pan
should never be above the FULL mark or below the
ADD OIL mark on dipstick. Either of these two con-
ditions could be responsible for noisy tappets.
OIL LEVEL
HIGH
If oil level is above the FULL mark, it is possible
for the connecting rods to dip into the oil. With the
engine running, this condition could create foam in
the oil pan. Foam in oil pan would be fed to the
hydraulic tappets by the oil pump causing them to
lose length and allow valves to seat noisily.LOW
Low oil level may allow oil pump to take in air.
When air is fed to the tappets, they lose length,
which allows valves to seat noisily. Any leaks on
intake side of oil pump through which air can be
drawn will create the same tappet action. Check the
lubrication system from the intake strainer to the
pump cover, including the relief valve retainer cap.
When tappet noise is due to aeration, it may be
intermittent or constant, and usually more than one
tappet will be noisy. When oil level and leaks have
been corrected, operate the engine at fast idle. Run
engine for a sufficient time to allow all of the air
inside the tappets to be bled out.
TAPPET NOISE DIAGNOSIS
(1) To determine source of tappet noise, operate
engine at idle with cylinder head covers removed.
(2) Feel each valve spring or rocker arm to detect
noisy tappet. The noisy tappet will cause the affected
spring and/or rocker arm to vibrate or feel rough in
operation.
NOTE: Worn valve guides or cocked springs are
sometimes mistaken for noisy tappets. If such is
the case, noise may be dampened by applying side
thrust on the valve spring. If noise is not apprecia-
bly reduced, it can be assumed the noise is in the
tappet. Inspect the rocker arm push rod sockets
and push rod ends for wear.
(3) Valve tappet noise ranges from light noise to a
heavy click. A light noise is usually caused by exces-
sive leak-down around the unit plunger, or by the
plunger partially sticking in the tappet body cylinder.
The tappet should be replaced. A heavy click is
caused by a tappet check valve not seating, or by for-
eign particles wedged between the plunger and the
tappet body. This will cause the plunger to stick in
the down position. This heavy click will be accompa-
nied by excessive clearance between the valve stem
and rocker arm as valve closes. In either case, tappet
assembly should be removed for inspection and clean-
ing.
(4) The valve train generates a noise very much
like a light tappet noise during normal operation.
Care must be taken to ensure that tappets are mak-
ing the noise. If more than one tappet seems to be
noisy, it's probably not the tappets.
LEAK-DOWN TEST
After cleaning and inspection, test each tappet for
specified leak-down rate tolerance to ensure zero-lash
operation (Fig. 36).
Swing the weighted arm of the hydraulic valve tap-
pet tester away from the ram of the Universal Leak-
Down Tester.
Fig. 35 Burnishing Distributor Driveshaft Bushing
1 - SPECIAL TOOL C-3053
2 - BUSHING
BR/BEENGINE 5.2L 9 - 95
DISTRIBUTOR BUSHING (Continued)