fuel type DODGE RAM 2001 Service User Guide

CONDITION POSSIBLE CAUSES CORRECTION
5. Pressure cap not installed tightly. If cap
is loose, boiling point of coolant will be
lowered. Also refer to the following Step
6.5. Tighten cap
6. Poor seals at the radiator cap. 6. (a) Check condition of cap and cap
seals. Refer to Radiator Cap. Replace
cap if necessary.
(b) Check condition of radiator filler neck.
If neck is bent or damaged, replace
radiator.
7. Coolant level low in radiator but not in
coolant reserve/overflow tank. This
means the radiator is not drawing coolant
from the coolant reserve/overflow tank as
the engine cools7. (a) Check condition of radiator cap and
cap seals. Refer to Radiator Cap in this
Group. Replace cap if necessary.
(b) Check condition of radiator filler neck.
If neck is bent or damaged, replace
radiator.
(c) Check condition of the hose from the
radiator to the coolant tank. It should fit
tight at both ends without any kinks or
tears. Replace hose if necessary.
(d) Check coolant reserve/overflow tank
and tanks hoses for blockage. Repair as
necessary.
8. Incorrect coolant concentration 8. Check coolant. (Refer to
LUBRICATION & MAINTENANCE/FLUID
TYPES - DESCRIPTION).
9. Coolant not flowing through system 9. Check for coolant flow at radiator filler
neck with some coolant removed, engine
warm and thermostat open. Coolant
should be observed flowing through
radiator. If flow is not observed, determine
area of obstruction and repair as
necessary.
10. Radiator or A/C condenser fins are
dirty or clogged.10. Remove insects and debris. (Refer to
7 - COOLING - STANDARD
PROCEDURE).
11. Radiator core is corroded or plugged. 11. Have radiator re-cored or replaced.
12. Aftermarket A/C installed without
proper radiator.12. Install proper radiator.
13. Fuel or ignition system problems. 13. Refer to 14 - Fuel System or 8 -
Electrical for diagnosis and testing
procedures.
14. Dragging brakes. 14. Check and correct as necessary.
(Refer to 5 - BRAKES - DIAGNOSIS AND
TESTING) for correct procedures.
15. Bug screen or cardboard is being
used, reducing airflow.15. Remove bug screen or cardboard.
7 - 8 COOLINGBR/BE
COOLING (Continued)

ENGINE COOLANT TEMP
SENSOR - 3.9L/5.2L/5.9L
DESCRIPTION
The Engine Coolant Temperature (ECT) sensor is
used to sense engine coolant temperature. The sensor
protrudes into an engine water jacket.
The ECT sensor is a two-wire Negative Thermal
Coefficient (NTC) sensor. Meaning, as engine coolant
temperature increases, resistance (voltage) in the
sensor decreases. As temperature decreases, resis-
tance (voltage) in the sensor increases.
OPERATION
At key-on, the Powertrain Control Module (PCM)
sends out a regulated 5 volt signal to the ECT sensor.
The PCM then monitors the signal as it passes
through the ECT sensor to the sensor ground (sensor
return).
When the engine is cold, the PCM will operate in
Open Loop cycle. It will demand slightly richer air-
fuel mixtures and higher idle speeds. This is done
until normal operating temperatures are reached.
The PCM uses inputs from the ECT sensor for the
following calculations:
²for engine coolant temperature gauge operation
through CCD or PCI (J1850) communications
²Injector pulse-width
²Spark-advance curves
²ASD relay shut-down times
²Idle Air Control (IAC) motor key-on steps
²Pulse-width prime-shot during cranking
²O2 sensor closed loop times
²Purge solenoid on/off times
²EGR solenoid on/off times (if equipped)
²Leak Detection Pump operation (if equipped)²Radiator fan relay on/off times (if equipped)
²Target idle speed
REMOVAL
WARNING: HOT, PRESSURIZED COOLANT CAN
CAUSE INJURY BY SCALDING. COOLING SYSTEM
MUST BE PARTIALLY DRAINED BEFORE REMOV-
ING THE COOLANT TEMPERATURE SENSOR.
REFER TO GROUP 7, COOLING.
(1) Partially drain cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE).
(2) Remove air cleaner assembly.
(3) Disconnect electrical connector from sensor
(Fig. 14).
(4)Engines with air conditioning:When
removing the connector from sensor, do not pull
directly on wiring harness. Fabricate an L-shaped
hook tool from a coat hanger (approximately eight
inches long). Place the hook part of tool under the
connector for removal. The connector is snapped onto
the sensor. It is not equipped with a lock type tab.
(5) Remove sensor from intake manifold.
INSTALLATION
(1) Install sensor.
(2) Tighten to 6±8 N´m (55±75 in. lbs.) torque.
(3) Connect electrical connector to sensor. The sen-
sor connector is symmetrical (not indexed). It can be
installed to the sensor in either direction.
(4) Install air cleaner assembly.
(5) Refill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
Fig. 13 Block HeaterÐDiesel Engine
1 - BLOCK HEATER
Fig. 14 Engine Coolant Temperature
1 - GENERATOR
2 - A/C COMPRESSOR
3 - ENGINE COOLANT TEMPERATURE SENSOR
4 - ELEC. CONN.
7 - 48 ENGINEBR/BE
ENGINE BLOCK HEATER - 5.9L DIESEL (Continued)

(5) Disconnect the instrument panel wire harness
connectors and the antenna coaxial cable connector
from the receptacles on the rear of the radio receiver.
(6) If so equipped, remove the screw that secures
the ground wire to the back of the radio receiver
chassis.
(7) Remove the radio receiver from the instrument
panel.
INSTALLATION
(1) Position the radio receiver to the instrument
panel.
(2) If so equipped, install and tighten the screw
that secures the ground wire to the back of the radio
receiver chassis. Tighten the screw to 7 N´m (65 in.
lbs.).
(3) Reconnect the instrument panel wire harness
connectors and the antenna coaxial cable connector
to the receptacles on the rear of the radio receiver.
(4) Position the radio receiver into the mounting
hole in the instrument panel.
(5) Install and tighten the two screws that secure
the radio receiver to the instrument panel. Tighten
the screws to 5 N´m (45 in. lbs.).
(6) Install the cluster bezel onto the instrument
panel.
(7) Reconnect the battery negative cable.
RADIO NOISE SUPPRESSION
COMPONENTS
DESCRIPTION
Radio Frequency Interference (RFI) and Electro-
Magnetic Interference (EMI) noise suppression is
accomplished primarily through circuitry internal to
the radio receivers. These internal suppression
devices are only serviced as part of the radio receiver.
External suppression devices that are used on this
vehicle to control RFI or EMI noise include the fol-
lowing:
²Radio antenna base ground
²Radio receiver chassis ground wire or strap
²Engine-to-body ground straps
²Cab-to-bed ground strap
²Heater core ground strap
²Resistor-type spark plugs
²Radio suppression-type secondary ignition wir-
ing.
For more information on the spark plugs and sec-
ondary ignition components, refer to Electrical, Igni-
tion Control.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - RADIO NOISE
SUPPRESSION COMPONENTS
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO ELECTRICAL, RESTRAINTS
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, OR INSTRUMENT PANEL
COMPONENT DIAGNOSIS OR SERVICE. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
For complete circuit diagrams, refer to the appro-
priate wiring information. The wiring information
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 connec-
tors, splices and grounds. Inspect the ground paths
and connections at the following locations:
²Blower motor
²Cab-to-bed ground strap
²Electric fuel pump
²Engine-to-body ground straps
²Generator
²Ignition module
²Heater core ground strap
²Radio antenna base ground
²Radio receiver chassis ground wire or strap
Fig. 9 Radio Receiver Connections - Typical
1 - ANTENNA CABLE
2 - RADIO
3 - INSTRUMENT PANEL WIRING
4 - GROUND WIRE
8A - 12 AUDIOBR/BE
RADIO (Continued)

DIESEL ENGINE
Diesel engine models feature a clamping type
female battery terminal made of soft lead die cast
onto one end of the battery cable wire. A square
headed pinch-bolt and hex nut are installed at the
open end of the female battery terminal clamp. The
pinch-bolt on the left side battery positive cable
female terminal clamp also has a stud extending
from the head of the bolt. Large eyelet type terminals
are crimped onto the opposite end of the battery
cable wire and then solder-dipped. The battery posi-
tive cable wires have a red insulating jacket to pro-
vide visual identification and feature a larger female
battery terminal clamp to allow connection to the
larger battery positive terminal post. The battery
negative cable wires have a black insulating jacket
and a smaller female battery terminal clamp.
OPERATION
The battery cables connect the battery terminal
posts to the vehicle electrical system. These cables
also provide a return path for electrical current gen-
erated by the charging system for restoring the volt-
age potential of the battery. The female battery
terminal clamps on the ends of the battery cable
wires provide a strong and reliable connection of the
battery cable to the battery terminal posts. The ter-
minal pinch bolts allow the female terminal clamps
to be tightened around the male terminal posts on
the top of the battery. The eyelet terminals secured
to the ends of the battery cable wires opposite the
female battery terminal clamps provide secure and
reliable connection of the battery to the vehicle elec-
trical system.
GASOLINE ENGINE
The battery positive cable terminal clamp is
crimped onto the ends of two wires. One wire has an
eyelet terminal that connects the battery positive
cable to the B(+) terminal stud of the Power Distri-
bution Center (PDC), and the other wire has an eye-
let terminal that connects the battery positive cable
to the B(+) terminal stud of the engine starter motor
solenoid. The battery negative cable terminal clamp
is also crimped onto the ends of two wires. One wire
has an eyelet terminal that connects the battery neg-
ative cable to the vehicle powertrain through a stud
on the front of the left engine cylinder head. The
other wire has an eyelet terminal that connects the
battery negative cable to the vehicle body through a
ground screw on the left front fender inner shield,
just ahead of the battery. An additional ground wire
with two eyelet terminals is used to provide ground
to the vehicle frame. One eyelet terminal of this
ground wire is installed under the head of the bat-
tery negative cable terminal clamp pinch-bolt, andthe other eyelet terminal is secured with a ground
screw to the outer surface of the left frame rail,
below the battery.
DIESEL ENGINE
The left battery positive cable terminal clamp is
die cast onto the ends of two wires. One wire has an
eyelet terminal that connects the left battery positive
cable to the B(+) terminal stud of the Power Distri-
bution Center (PDC), and the other wire has an eye-
let terminal that connects the left battery positive
cable to the B(+) terminal stud of the engine starter
motor solenoid. The right battery positive cable ter-
minal clamp is die cast onto the end of a single wire.
The eyelet terminal on the other end of the right bat-
tery positive cable is connected to the stud on the
pinch-bolt of the left battery positive cable terminal
clamp. This stud also provides a connection point for
the eyelet terminals from the fuel heater relay and
intake air heater relay jumper harness take outs. All
of these eyelet terminals are secured to the left bat-
tery positive cable terminal clamp pinch-bolt stud
with a single hex nut.
The left battery negative cable terminal clamp is
die cast onto the ends of two wires. One wire has an
eyelet terminal that connects the left battery nega-
tive cable to the vehicle powertrain through a ground
screw on the left side of the engine block, below the
power steering and vacuum pumps. The other wire
has an eyelet terminal that connects the left battery
negative cable to the vehicle body through a ground
screw on the left front fender inner shield, just ahead
of the left battery. An additional ground wire with
two eyelet terminals is used to provide ground to the
vehicle frame. One eyelet terminal of this ground
wire is installed under the nut of the left battery
negative cable terminal clamp pinch-bolt, and the
other eyelet terminal is secured with a ground screw
to the outer surface of the left frame rail, below the
left battery. The right battery negative cable terminal
is also die cast onto the ends of two wires. One wire
has an eyelet terminal that connects the right bat-
tery negative cable to the vehicle powertrain through
a ground screw on the right side of the engine block,
just forward of the right engine mount. The other
wire has an eyelet terminal that connects the right
battery negative cable to the vehicle body through a
ground screw on the right front fender inner shield,
just behind the right battery.
DIAGNOSIS & TESTING - BATTERY CABLES
A voltage drop test will determine if there is exces-
sive resistance in the battery cable terminal connec-
tions or the battery cables. If excessive resistance is
found in the battery cable connections, the connec-
tion point should be disassembled, cleaned of all cor-
8F - 20 BATTERY SYSTEMBR/BE
BATTERY CABLE (Continued)

SPARK PLUG CABLE RESISTANCE
MINIMUM MAXIMUM
250 Ohms Per Inch 1000 Ohms Per Inch
3000 Ohms Per Foot 12,000 Ohms Per Foot
SPARK PLUGS
ENGINE PLUG TYPE ELECTRODE GAP
3.9L V-6 RC12LC4 1.01 mm (.040 in.)
5.2L/5.9L V-8 RC12LC4 1.01 mm (.040 in.)
8.0L V-10 QC9MC4 1.14 mm (.045 in.)
IGNITION COIL RESISTANCEÐ3.9L/5.2L/5.9L ENGINES
COIL MANUFACTURERPRIMARY RESISTANCE
21-27ÉC (70-80ÉF)SECONDARY RESISTANCE 21-27ÉC
(70-80ÉF)
Diamond 0.97 - 1.18 Ohms 11,300 - 15,300 Ohms
Toyodenso 0.95 - 1.20 Ohms 11,300 - 13,300 Ohms
IGNITION COIL RESISTANCEÐ8.0L V-10
ENGINE
Primary Resistance: 0.53-0.65 Ohms. Test across the
primary connector. Refer to text for test procedures.
Secondary Resistance: 10.9-14.7K Ohms. Test
across the individual coil towers. Refer to text for test
procedures.
IGNITION TIMING
Ignition timing is not adjustable on any engine.
AUTOMATIC SHUT DOWN
RELAY
DESCRIPTION - PCM OUTPUT
The 5±pin, 12±volt, Automatic Shutdown (ASD)
relay is located in the Power Distribution Center
(PDC). Refer to label on PDC cover for relay location.
OPERATION - PCM OUTPUT
The ASD relay supplies battery voltage (12+ volts)
to the fuel injectors and ignition coil(s). With certain
emissions packages it also supplies 12±volts to the
oxygen sensor heating elements.
The ground circuit for the coil within the ASD
relay is controlled by the Powertrain Control Module
(PCM). The PCM operates the ASD relay by switch-
ing its ground circuit on and off.The ASD relay will be shut±down, meaning the
12±volt power supply to the ASD relay will be de-ac-
tivated by the PCM if:
²the ignition key is left in the ON position. This
is if the engine has not been running for approxi-
mately 1.8 seconds.
²there is a crankshaft position sensor signal to
the PCM that is lower than pre-determined values.
OPERATION - ASD SENSE - PCM INPUT
A 12 volt signal at this input indicates to the PCM
that the ASD has been activated. The relay is used to
connect the oxygen sensor heater element, ignition
coil and fuel injectors to 12 volt + power supply.
This input is used only to sense that the ASD relay
is energized. If the Powertrain Control Module
(PCM) does not see 12 volts at this input when the
ASD should be activated, it will set a Diagnostic
Trouble Code (DTC).
DIAGNOSIS AND TESTING - ASD AND FUEL
PUMP RELAYS
The following description of operation and
tests apply only to the Automatic Shutdown
(ASD) and fuel pump relays. The terminals on the
bottom of each relay are numbered. Two different
types of relays may be used, (Fig. 1) or (Fig. 2).
²Terminal number 30 is connected to battery volt-
age. For both the ASD and fuel pump relays, termi-
nal 30 is connected to battery voltage at all times.
BR/BEIGNITION CONTROL 8I - 3
IGNITION CONTROL (Continued)

²The PCM grounds the coil side of the relay
through terminal number 85.
²Terminal number 86 supplies voltage to the coil
side of the relay.
²When the PCM de-energizes the ASD and fuel
pump relays, terminal number 87A connects to termi-
nal 30. This is the Off position. In the off position,
voltage is not supplied to the rest of the circuit. Ter-
minal 87A is the center terminal on the relay.²When the PCM energizes the ASD and fuel
pump relays, terminal 87 connects to terminal 30.
This is the On position. Terminal 87 supplies voltage
to the rest of the circuit.
The following procedure applies to the ASD and
fuel pump relays.
(1) Remove relay from connector before testing.
(2) With the relay removed from the vehicle, use
an ohmmeter to check the resistance between termi-
nals 85 and 86. The resistance should be 75 ohms +/-
5 ohms.
(3) Connect the ohmmeter between terminals 30
and 87A. The ohmmeter should show continuity
between terminals 30 and 87A.
(4) Connect the ohmmeter between terminals 87
and 30. The ohmmeter should not show continuity at
this time.
(5) Connect one end of a jumper wire (16 gauge or
smaller) to relay terminal 85. Connect the other end
of the jumper wire to the ground side of a 12 volt
power source.
(6) Connect one end of another jumper wire (16
gauge or smaller) to the power side of the 12 volt
power source.Do not attach the other end of the
jumper wire to the relay at this time.
WARNING: DO NOT ALLOW OHMMETER TO CON-
TACT TERMINALS 85 OR 86 DURING THIS TEST.
DAMAGE TO OHMMETER MAY RESULT.
(7) Attach the other end of the jumper wire to
relay terminal 86. This activates the relay. The ohm-
meter should now show continuity between relay ter-
minals 87 and 30. The ohmmeter should not show
continuity between relay terminals 87A and 30.
(8) Disconnect jumper wires.
(9) Replace the relay if it did not pass the continu-
ity and resistance tests. If the relay passed the tests,
it operates properly. Check the remainder of the ASD
and fuel pump relay circuits. Refer to 8, Wiring Dia-
grams.
REMOVAL
The ASD relay is located in the Power Distribution
Center (PDC) (Fig. 3). 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.
Fig. 1 ASD and Fuel Pump Relay TerminalsÐType 1
TERMINAL LEGEND
NUMBER IDENTIFICATION
30 COMMON FEED
85 COIL GROUND
86 COIL BATTERY
87 NORMALLY OPEN
87A NORMALLY CLOSED
Fig. 2 ASD and Fuel Pump Relay TerminalsÐType 2
TERMINAL LEGEND
NUMBER IDENTIFICATION
30 COMMON FEED
85 COIL GROUND
86 COIL BATTERY
87 NORMALLY OPEN
87A NORMALLY CLOSED
8I - 4 IGNITION CONTROLBR/BE
AUTOMATIC SHUT DOWN RELAY (Continued)

SPARK PLUG
DESCRIPTION
The 3.9L V-6 and 5.2L/5.9L V-8 engines use resis-
tor type spark plugs. The 8.0L V-10 engine uses
inductive type spark plugs.
Spark plug resistance values range from 6,000 to
20,000 ohms (when checked with at least a 1000 volt
spark plug tester).Do not use an ohmmeter to
check the resistance values of the spark plugs.
Inaccurate readings will result.
OPERATION
To prevent possible pre-ignition and/or mechanical
engine damage, the correct type/heat range/number
spark plug must be used.
Always use the recommended torque when tighten-
ing spark plugs. Incorrect torque can distort the
spark plug and change plug gap. It can also pull the
plug threads and do possible damage to both the
spark plug and the cylinder head.
Remove the spark plugs and examine them for
burned electrodes and fouled, cracked or broken por-
celain insulators. Keep plugs arranged in the order
in which they were removed from the engine. A sin-gle plug displaying an abnormal condition indicates
that a problem exists in the corresponding cylinder.
Replace spark plugs at the intervals recommended in
Group O, Lubrication and Maintenance
Spark plugs that have low mileage may be cleaned
and reused if not otherwise defective, carbon or oil
fouled. Also refer to Spark Plug Conditions.
CAUTION: Never use a motorized wire wheel brush
to clean the spark plugs. Metallic deposits will
remain on the spark plug insulator and will cause
plug misfire.
DIAGNOSIS AND TESTING - SPARK PLUG
CONDITIONS
NORMAL OPERATING
The few deposits present on the spark plug will
probably be light tan or slightly gray in color. This is
evident with most grades of commercial gasoline
(Fig. 29). There will not be evidence of electrode
burning. Gap growth will not average more than
approximately 0.025 mm (.001 in) per 3200 km (2000
miles) of operation. Spark plugs that have normal
wear can usually be cleaned, have the electrodes
filed, have the gap set and then be installed.
Some fuel refiners in several areas of the United
States have introduced a manganese additive (MMT)
for unleaded fuel. During combustion, fuel with MMT
causes the entire tip of the spark plug to be coated
with a rust colored deposit. This rust color can be
misdiagnosed as being caused by coolant in the com-
bustion chamber. Spark plug performance may be
affected by MMT deposits.
Fig. 28 Spark Plug Cable OrderÐ8.0L V-10 Engine
Fig. 29 Normal Operation and Cold (Carbon) Fouling
1 - NORMAL
2 - DRY BLACK DEPOSITS
3 - COLD (CARBON) FOULING
8I - 16 IGNITION CONTROLBR/BE
IGNITION COIL (Continued)

²Check Gauges Indicator
²Cruise Indicator (Odometer VFD)
²Four-Wheel Drive Indicator
²High Beam Indicator
²Low Fuel Indicator
²Washer Fluid Indicator
²Malfunction Indicator Lamp (MIL)
²Overdrive-Off Indicator
²Seatbelt Indicator
²Service Reminder Indicator (SRI)
²Transmission Overtemp Indicator
²Turn Signal (Right and Left) Indicators
²Upshift Indicator
²Wait-To-Start Indicator (Diesel Only)
²Water-In-Fuel Indicator (Diesel Only)
Some of these indicators are either programmable
or automatically configured when the EMIC is con-
nected to the vehicle electrical system. This feature
allows those indicators to be activated or deactivated
for compatibility with certain optional equipment.
The EMIC also includes a provision for mounting the
automatic transmission gear selector indicator in the
lower right corner of the cluster. The spring-loaded,
cable driven, mechanical gear selector indicator gives
an indication of the transmission gear that has been
selected with the automatic transmission gear selec-
tor lever. The gear selector indicator pointer is easily
visible through an opening provided in the front of
the cluster overlay, and is also lighted by the cluster
illumination lamps for visibility at night. Models
equipped with a manual transmission have a block-
out plate installed in place of the gear selector indi-
cator.
Cluster illumination is accomplished by adjustable
incandescent back lighting, which illuminates the
gauges for visibility when the exterior lighting is
turned on. The EMIC high beam indicator, turn sig-
nal indicators, and wait-to-start indicator are also
illuminated by dedicated incandescent bulbs. The
remaining indicators in the EMIC are each illumi-
nated by a dedicated Light Emitting Diode (LED)
that is soldered onto the electronic circuit board.
Each of the incandescent bulbs is secured by an inte-
gral bulb holder to the electronic circuit board from
the back of the cluster housing.
Hard wired circuitry connects the EMIC to the
electrical system of the vehicle. These hard wired cir-
cuits are integral to several wire harnesses, which
are routed throughout the vehicle and retained by
many different methods. These circuits may be con-
nected to each other, to the vehicle electrical system
and to the EMIC through the use of a combination of
soldered splices, splice block connectors, and many
different types of wire harness terminal connectors
and insulators. Refer to the appropriate wiring infor-
mation. The wiring information includes wiring dia-grams, proper wire and connector repair procedures,
further details on wire harness routing and reten-
tion, as well as pin-out and location views for the
various wire harness connectors, splices and grounds.
The EMIC modules for this model are serviced only
as complete units. The EMIC module cannot be
adjusted or repaired. If a gauge, an LED indicator,
the VFD, the electronic circuit board, the circuit
board hardware, the cluster overlay, or the EMIC
housing are damaged or faulty, the entire EMIC mod-
ule must be replaced. The cluster lens and hood unit,
the rear cluster housing cover, the automatic trans-
mission gear selector indicator, and the incandescent
lamp bulbs with holders are available for individual
service replacement.
OPERATION
The ElectroMechanical Instrument Cluster (EMIC)
is designed to allow the vehicle operator to monitor
the conditions of many of the vehicle components and
operating systems. The gauges and indicators in the
EMIC provide valuable information about the various
standard and optional powertrains, fuel and emis-
sions systems, cooling systems, lighting systems,
safety systems and many other convenience items.
The EMIC is installed in the instrument panel so
that all of these monitors can be easily viewed by the
vehicle operator when driving, while still allowing
relative ease of access for service. The microproces-
sor-based EMIC hardware and software uses various
inputs to control the gauges and indicators visible on
the face of the cluster. Some of these inputs are hard
wired, but most are in the form of electronic mes-
sages that are transmitted by other electronic mod-
ules over the Chrysler Collision Detection (CCD) data
bus network. (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/COMMUNICATION
- OPERATION).
The EMIC microprocessor smooths the input data
using algorithms to provide gauge readings that are
accurate, stable and responsive to operating condi-
tions. These algorithms are designed to provide
gauge readings during normal operation that are con-
sistent with customer expectations. However, when
abnormal conditions exist, such as low/high battery
voltage, low oil pressure, or high coolant tempera-
ture, the algorithm drives the gauge pointer to an
extreme position and the microprocessor turns on the
Check Gauges indicator to provide a distinct visual
indication of a problem to the vehicle operator. The
instrument cluster circuitry may also generate a
hard wired chime tone request to the Central Timer
Module (CTM) when it monitors certain conditions or
inputs, in order to provide the vehicle operator with
an audible alert.
BR/BEINSTRUMENT CLUSTER 8J - 3
INSTRUMENT CLUSTER (Continued)

ENGINE 3.9L
DESCRIPTION
The 3.9 Liter (238 CID) six-cylinder engine is a
V-Type, lightweight, single cam, overhead valve
engine with hydraulic roller tappets. This engine is
designed to use unleaded fuel.
The engine lubrication system consists of a rotor
type oil pump and a full-flow oil filter.
The cylinders are numbered from front to rear; 1,
3, 5 on the left bank and 2, 4, 6 on the right bank.
The firing order is 1-6-5-4-3-2 (Fig. 1).
The engine serial number is stamped into a
machined pad located on the left front corner of the
cylinder block. When component part replacement is
necessary, use the engine type and serial number for
reference (Fig. 2).
DIAGNOSIS AND TESTINGÐENGINE
DIAGNOSIS - INTRODUCTION
Engine diagnosis is helpful in determining the
causes of malfunctions not detected and remedied by
routine maintenance.
These malfunctions may be classified as either
mechanical (e.g., a strange noise), or performance
(e.g., engine idles rough and stalls).
(Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING - Preformance) or (Refer to 9 - ENGINE - DIAG-
NOSIS AND TESTING - Mechanical). Refer to 14 -
FUEL SYSTEM for fuel system diagnosis.
Additional tests and diagnostic procedures may be
necessary for specific engine malfunctions that can-
not be isolated with the Service Diagnosis charts.
Information concerning additional tests and diagno-
sis is provided within the following:
²Cylinder Compression Pressure Test
²Cylinder Combustion Pressure Leakage Test
²Cylinder Head Gasket Failure Diagnosis
²Intake Manifold Leakage Diagnosis
²Lash Adjuster (Tappet) Noise Diagnosis
²Engine Oil Leak Inspection
Fig. 1 Firing Order
Fig. 2 Engine Identification (Serial) Number
BR/BEENGINE 3.9L 9 - 3
ENGINE 3.9L (Continued)

(4) A controlled hone motor speed between 200 and
300 RPM is necessary to obtain the proper cross-
hatch angle. The number of up and down strokes per
minute can be regulated to get the desired 50É to 60É
angle. Faster up and down strokes increase the cross-
hatch angle.
(5) After honing, it is necessary that the block be
cleaned to remove all traces of abrasive. Use a brush
to wash parts with a solution of hot water and deter-
gent. Dry parts thoroughly. Use a clean, white, lint-
free cloth to check that the bore is clean. Oil the
bores after cleaning to prevent rusting.
STANDARD PROCEDUREÐHYDROSTATIC
LOCK
CAUTION: DO NOT use the starter motor to rotate
the crankshaft. Severe damage could occur.
When an engine is suspected of hydrostatic lock
(regardless of what caused the problem), follow the
steps below.
(1) Perform the Fuel Pressure Release Procedure
(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY -
STANDARD PROCEDURE).
(2) Disconnect the negative cable(s) from the bat-
tery.
(3) Inspect air cleaner, induction system, and
intake manifold to ensure system is dry and clear of
foreign material.
(4) Place a shop towel around the spark plugs to
catch any fluid that may possibly be under pressure
in the cylinder head. Remove the spark plugs.
(5) With all spark plugs removed, rotate the crank-
shaft using a breaker bar and socket.
(6) Identify the fluid in the cylinders (coolant, fuel,
oil, etc.).
(7) Be sure all fluid has been removed from the
cylinders.
(8) Repair engine or components as necessary to
prevent this problem from occurring again.
(9) Squirt a small amount of engine oil into the
cylinders to lubricate the walls. This will prevent
damage on restart.
(10) Install new spark plugs. Tighten the spark
plugs to 41 N´m (30 ft. lbs.) torque.
(11) Drain engine oil. Remove and discard the oil
filter.
(12) Install the drain plug. Tighten the plug to 34
N´m (25 ft. lbs.) torque.
(13) Install a new oil filter.
(14) Fill engine crankcase with the specified
amount and grade of oil. (Refer to LUBRICATION &
MAINTENANCE - SPECIFICATIONS).
(15) Connect the negative cable(s) to the battery.
(16) Start the engine and check for any leaks.
STANDARD PROCEDUREÐREPAIR DAMAGED
OR WORN THREADS
CAUTION: Be sure that the tapped holes maintain
the original center line.
Damaged or worn threads can be repaired. Essen-
tially, this repair consists of:
²Drilling out worn or damaged threads.
²Tapping the hole with a special Heli-Coil Tap, or
equivalent.
²Installing an insert into the tapped hole to bring
the hole back to its original thread size.
STANDARD PROCEDUREÐFORM-IN-PLACE
GASKETS & SEALERS
There are numerous places where form-in-place
gaskets are used on the engine. Care must be taken
when applying form-in-place gaskets to assure
obtaining the desired results.Do not use form-in-
place gasket material unless specified.Bead size,
continuity, and location are of great importance. Too
thin a bead can result in leakage while too much can
result in spill-over which can break off and obstruct
fluid feed lines. A continuous bead of the proper
width is essential to obtain a leak-free gasket.
There are numerous types of form-in-place gasket
materials that are used in the engine area. Mopart
Engine RTV GEN II, MopartATF-RTV, and Mopart
Gasket Maker gasket materials, each have different
properties and can not be used in place of the other.
MOPARtENGINE RTV GEN II
MopartEngine RTV GEN II is used to seal com-
ponents exposed to engine oil. This material is a spe-
cially designed black silicone rubber RTV that
retains adhesion and sealing properties when
exposed to engine oil. Moisture in the air causes the
material to cure. This material is available in three
ounce tubes and has a shelf life of one year. After one
year this material will not properly cure. Always
inspect the package for the expiration date before
use.
MOPARtATF RTV
MopartATF RTV is a specifically designed black
silicone rubber RTV that retains adhesion and seal-
ing properties to seal components exposed to auto-
matic transmission fluid, engine coolants, and
moisture. This material is available in three ounce
tubes and has a shelf life of one year. After one year
this material will not properly cure. Always inspect
the package for the expiration date before use.
MOPARtGASKET MAKER
MopartGasket Maker is an anaerobic type gasket
material. The material cures in the absence of air
when squeezed between two metallic surfaces. It will
not cure if left in the uncovered tube. The anaerobic
BR/BEENGINE 3.9L 9 - 11
ENGINE 3.9L (Continued)