oil filter DODGE RAM 2001 Service Owner's Manual

26,250 Miles (42 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
30,000 Miles (48 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect fan hub.
²Inspect damper.
²Inspect water pump weep hole for blockage.
²Replace fuel filter and clean water in fuel sen-
sor.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect front wheel bearings. Clean and repack,
if required (4x2).
²Inspect brake linings.
33,700 Miles (54 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
37,500 Miles (60 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Replace fuel filter and clean water in fuel sen-
sor.
41,250 Miles (66 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
45,000 Miles (72 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect drive belts, replace as necessary.
²Inspect water pump weep hole for blockage.
²Replace fuel filter and clean water in fuel sen-
sor.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Drain and refill transfer case fluid.
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect brake linings.
48,750 Miles (78,000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
52,500 Miles (84 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Replace fuel filter and clean water in fuel sen-
sor.
56,250 Miles (90 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
60,000 Miles (96 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect fan hub.
²Inspect damper.
²Inspect water pump weep hole for blockage.
²Replace fuel filter and clean water in fuel sen-
sor.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect front wheel bearings. Clean and repack
if required (4x2).
²Inspect brake linings.
²Flush and replace engine coolant.
63,750 Miles (102 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
67,500 Miles (108 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect drive belts, replace as necessary.
²Replace fuel filter and clean water in fuel sen-
sor.
71,250 Miles (114 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
75,000 Miles (120 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect water pump weep hole for blockage.
²Replace fuel filter and clean water in fuel sen-
sor.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect brake linings.
78,750 Miles (126 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
82,500 Miles (132 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Replace fuel filter and clean water in fuel sen-
sor.
BR/BELUBRICATION & MAINTENANCE 0 - 25
MAINTENANCE SCHEDULES (Continued)

86,250 Miles (138 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
90,000 Miles (144 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect drive belts, replace as necessary.
²Inspect fan hub.
²Inspect damper.
²Inspect water pump weep hole for blockage.
²
Replace fuel filter and clean water in fuel sensor.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Drain and refill transfer case fluid.
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect front wheel bearings. Clean and repack
if required (4x2).
²Inspect brake linings.
93,750 Miles (150 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
97,500 Miles (156 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Flush and replace engine coolant.
²Replace fuel filter and clean water in fuel sen-
sor.
²Adjust rear brakes.
101,250 Miles (162 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
105,000 Miles (168 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect water pump weep hole for blockage.
²Replace fuel filter and clean water in fuel sen-
sor.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect brake linings.
108,750 Miles (174 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
112,500 Miles (180 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect drive belts, replace as necessary.²
Replace fuel filter and clean water in fuel sensor.
116,250 Miles (186 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
120,000 Miles (192 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect fan hub.
²Inspect damper.
²Inspect water pump weep hole for blockage.
²Replace fuel filter and clean water in fuel sen-
sor.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect front wheel bearings. Clean and repack
if required (4x2).
²Inspect brake linings.
123,750 Miles (198 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
127,500 Miles (204 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Replace fuel filter and clean water in fuel sen-
sor.
131,250 Miles (210 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
135,000 Miles (216 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Clean inside of engine air cleaner element hous-
ing.
²Inspect drive belts, replace as necessary.
²Inspect water pump weep hole for blockage.
²Replace fuel filter and clean water in fuel sen-
sor.
²Adjust valve lash clearance
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Drain and refill transfer case fluid.
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect brake linings.
²Flush and replace engine coolant.
²Adjust rear brakes
Inspection and service should also be performed
anytime a malfunction is observed or suspected.
0 - 26 LUBRICATION & MAINTENANCEBR/BE
MAINTENANCE SCHEDULES (Continued)

(3) Inspect fan assembly for cracks, bends, loose
rivets or broken welds. Replace fan if any damage is
found.
INSTALLATION
(1) Install fan blade assembly to viscous fan drive.
Tighten mounting bolts to 23 N´m (17 ft. lbs.) torque.
(2) Position the fan shroud and fan blade/viscous
fan drive to the vehicle as an assembly.
(3) Install viscous fan drive assembly on fan hub
shaft (Fig. 7). Tighten mounting nut to 57 N´m (42 ft.
lbs.) torque.
(4) Install fan shroud bolts into position and
tighten the mounting bolts to 6 N´m (50 in. lbs.)
torque.
(5) Connect the battery negative cables.
NOTE: Viscous Fan Drive Fluid Pump Out Require-
ment: After installing a new viscous fan drive, bring
the engine speed up to approximately 2000 rpm and
hold for approximately two minutes. This will
ensure proper fluid distribution within the drive.
ENGINE BLOCK HEATER -
3.9L/5.2L/5.9L
DESCRIPTION
WARNING: DO NOT OPERATE ENGINE UNLESS
BLOCK HEATER CORD HAS BEEN DISCONNECTED
FROM POWER SOURCE AND SECURED IN PLACE.
THE POWER CORD MUST BE SECURED IN ITS
RETAINING CLIPS AND ROUTED AWAY FROM
EXHAUST MANIFOLDS AND MOVING PARTS.
An optional engine block heater is available on all
models. The heater is equipped with a power cord.
The heater is mounted in a core hole of the engine
cylinder block (in place of a freeze plug) with the
heating element immersed in engine coolant. The
cord is attached to an engine compartment compo-
nent with tie-straps.
The 3.9L and 5.9L gas powered engine has the
block heater located on the right side of engine next
to the oil filter (Fig. 8).
OPERATION
The heater warms the engine coolant providing
easier engine starting and faster warm-up in low
temperatures. Connecting the power cord to a
grounded 110-120 volt AC electrical outlet with a
grounded three wire extension cord provides the elec-
tricity needed to heat the element..
REMOVAL
(1) Disconnect battery negative cable.
(2) Drain coolant (Refer to 7 - COOLING - STAN-
DARD PROCEDURE).
(3) Remove power cord from heater by unplugging
(Fig. 9).
(4) Loosen (but do not completely remove) the
screw at center of block heater (Fig. 9).
(5) Remove block heater by carefully prying from
side-to-side. Note direction of heating element coil
(up or down). Element coil must be installed correctly
to prevent damage.
INSTALLATION
(1) Clean and inspect the block heater hole.
(2) Install new O-ring seal(s) to heater in gasoline
engines.
(3) Insert block heater into cylinder block.
(4) With heater fully seated, tighten center screw
to 2 N´m (17 in. lbs.).
(5) Fill cooling system with recommended coolant.
(Refer to 7 - COOLING - STANDARD PROCE-
DURE).
(6) Start and warm the engine.
(7) Check block heater for leaks.
Fig. 8 Engine Block Heater
1 - FREEZE PLUG HOLE
2 - BLOCK HEATER
3 - SCREW
4 - POWER CORD (120V AC)
5 - HEATING COIL
6 - OIL FILTER
BR/BEENGINE 7 - 45
RADIATOR FAN - 5.9L DIESEL (Continued)

ENGINE BLOCK HEATER - 8.0L
DESCRIPTION
An optional engine block heater is available on all
models. The heater is equipped with a power cord.
The heater is mounted in a core hole of the engine
cylinder block (in place of a freeze plug) with the
heating element immersed in engine coolant. The
cord is attached to an engine compartment compo-
nent with tie-straps.
The 8.0L V-10 engine has the block heater located
on the right side of engine next to the engine oil dip-
stick tube (Fig. 10).
WARNING: DO NOT OPERATE ENGINE UNLESS
BLOCK HEATER CORD HAS BEEN DISCONNECTED
FROM POWER SOURCE AND SECURED IN PLACE.
THE POWER CORD MUST BE SECURED IN ITS
RETAINING CLIPS AND ROUTED AWAY FROM
EXHAUST MANIFOLDS AND MOVING PARTS.
OPERATION
The heater warms the engine coolant providing
easier engine starting and faster warm-up in low
temperatures. Connecting the power cord to agrounded 110-120 volt AC electrical outlet with a
grounded three wire extension cord provides the elec-
tricity needed to heat the element..
REMOVAL
(1) Disconnect battery negative cable.
(2) Drain coolant from radiator and cylinder block
(Refer to 7 - COOLING - STANDARD PROCE-
DURE).
(3) Remove power cord from heater by unplugging
(Fig. 11).
(4) Loosen (but do not completely remove) the
screw at center of block heater (Fig. 11).
(5) Remove block heater by carefully prying from
side-to-side. Note direction of heating element coil
(up or down). Element coil must be installed correctly
to prevent damage.
INSTALLATION
(1) Clean and inspect the block heater hole.
(2) Install new O-ring seal(s) to heater in gasoline
engines.
(3) Insert block heater into cylinder block.
(4) With heater fully seated, tighten center screw
to 2 N´m (17 in. lbs.).
Fig. 9 Engine Block Heater
1 - FREEZE PLUG HOLE
2 - BLOCK HEATER
3 - SCREW
4 - POWER CORD (120V AC)
5 - HEATING COIL
6 - OIL FILTER
Fig. 10 Engine Block HeaterÐ8.0L V-10 Engine
1 - FREEZE PLUG HOLE
2 - SCREW
3 - POWER CORD (120V AC)
4 - BLOCK HEATER
5 - HEATING COIL
7 - 46 ENGINEBR/BE
ENGINE BLOCK HEATER - 3.9L/5.2L/5.9L (Continued)

ENGINE CONTROL MODULE
DESCRIPTION - ECM
The ECM is bolted to the left side of the engine
behind the fuel filter (Fig. 14). It is a separate com-
ponent and can be serviced. The FPCM is internal to
the fuel injection pump (Fig. 15) and cannot be ser-
viced.
OPERATION - ECM
The main functions of the Engine Control Module
(ECM) and Fuel Injection Pump Control Module
(FPCM) are to electrically control the fuel system.
The Powertrain Control Module (PCM)does not
controlthe fuel system.
The ECM can adapt its programming to meet
changing operating conditions.If the ECM has
been replaced, flashed or re-calibrated, the
ECM must learn the Accelerator Pedal Position
Sensor (APPS) idle voltage. Failure to learn
this voltage may result in unnecessary diagnos-
tic trouble codes. Refer to ECM Removal/Instal-
lation for learning procedures.
The ECM receives input signals from various
switches and sensors. Based on these inputs, the
ECM regulates various engine and vehicle operations
through different system components. These compo-
nents are referred to asECM Outputs.The sensors
and switches that provide inputs to the ECM are
consideredECM Inputs.NOTE: ECM Inputs:
²Accelerator Pedal Position Sensor (APPS) Volts
²APPS Idle Validation Switches #1 and #2
²Battery voltage
²Camshaft Position Sensor (CMP)
²CCD bus (+) circuits
²CCD bus (-) circuits
²Crankshaft Position Sensor (CKP)
²Data link connection for DRB scan tool
²(FPCM) Fuel Injection Pump Control Module
²Engine Coolant Temperature (ECT) sensor
²Ground circuits
²Intake manifold Air Temperature (IAT) sensor
²Manifold Air Pressure Sensor (Boost Pressure
Sensor)
²Oil pressure sensor
²PCM
²Power Take Off (PTO)
²Power ground
²Sensor return
²Signal ground
²Water-In-Fuel (WIF) sensor
Fig. 14 Engine Control Module (ECM) Location
1 - ENGINE CONTROL MODULE (ECM)
2 - HEX HEADED BOLT
3 - 50-WAY CONNECTOR
4 - FUEL TRANSFER PUMP
5 - MOUNTING BOLTS (3)
Fig. 15 Fuel Injection Pump Control Module (FPCM)
Location
1 - FPCM ELECTRICAL CONNECTOR
2 - HIGH-PRESSURE FUEL LINES
3 - FITTINGS
4 - FUEL INJECTION PUMP
5 - FPCM
BR/BEELECTRONIC CONTROL MODULES 8E - 13

NOTE: ECM Outputs:
After inputs are received by the ECM, certain sen-
sors, switches and components are controlled or reg-
ulated by the ECM. These are consideredECM
Outputs.These outputs are for:
²CCD bus (+) circuits
²CCD bus (-) circuits
²CKP and APPS outputs to the PCM
²Data link connection for DRB scan tool
²Five volt sensor supply
²Fuel injection pump
²Fuel injection pump relay
²(FPCM) Fuel Pump Control Module
²Fuel transfer (lift) pump
²Intake manifold air heater relays #1 and #2 con-
trol circuits
²Malfunction indicator lamp (Check engine lamp)
²Oil pressure gauge/warning lamp
²PCM
²Wait-to-start warning lamp
²Water-In-Fuel (WIF) warning lamp
REMOVAL
The ECM is bolted to the engine block behind the
fuel filter (Fig. 16).
(1) Record any Diagnostic Trouble Codes (DTC's)
found in the PCM or ECM.To avoid possible voltage spike damage to either
the Powertrain Control Module (PCM) or ECM, igni-
tion key must be off, and negative battery cables
must be disconnected before unplugging ECM con-
nectors.
(2) Disconnect both negative battery cables at both
batteries.
(3) Remove 50±way electrical connector bolt at
ECM (Fig. 16). Note: Connector bolt is female 4mm
hex head. To remove bolt, use a ball-hex bit or ball-
hex screwdriver such as Snap-Ont4mm SDABM4
(5/32º may also be used). As bolt is being removed,
very carefully remove connector from ECM.
(4) Remove three ECM mounting bolts and remove
ECM from vehicle.
INSTALLATION
Do not apply paint to back of ECM. Poor ground
will result.
(1) Clean ECM mounting points at engine block.
(2) Position ECM to engine block and install 3
mounting bolts. Tighten bolts to 24 N´m (18 ft. lbs.).
(3) Check pin connectors in ECM and 50±way con-
nector for corrosion or damage. Repair as necessary.
(4) Clean pins in 50±way electrical connector with
a quick-dry electrical contact cleaner.
(5) Very carefully install 50±way connector to
ECM. Tighten connector hex bolt.
(6) Install battery cables.
(7)Turn key to ON position. Without starting
engine, slowly press throttle pedal to floor and
then slowly release. This step must be done
(one time) to ensure accelerator pedal position
sensor calibration has been learned by ECM. If
not done, possible DTC's may be set.
(8) Use DRB scan tool to erase any stored compan-
ion DTC's from PCM.
POWERTRAIN CONTROL
MODULE
DESCRIPTION - PCM
The Powertrain Control Module (PCM) is located
in the engine compartment (Fig. 17). The PCM is
referred to as JTEC.
DESCRIPTION - MODES OF OPERATION
As input signals to the Powertrain Control Module
(PCM) change, the PCM adjusts its response to the
output devices. For example, the PCM must calculate
different injector pulse width and ignition timing for
idle than it does for wide open throttle (WOT).
The PCM will operate in two different modes:
Open Loop and Closed Loop.
Fig. 16 Engine Control Module (ECM) Location and
Mounting
1 - ENGINE CONTROL MODULE (ECM)
2 - HEX HEADED BOLT
3 - 50-WAY CONNECTOR
4 - FUEL TRANSFER PUMP
5 - MOUNTING BOLTS (3)
8E - 14 ELECTRONIC CONTROL MODULESBR/BE
ENGINE CONTROL MODULE (Continued)

Connector Name/Number Color Location Fig.
Cummins Bus (-) Left Front of Engine 10
Cup Holder Lamp Center of Instrument Panel 23,26
Data Link Connector BK Left Bottom of Instrument Panel 23,24
Day/Night Mirror BK Day/Night Mirror N/S
Daytime Running Lamp Module BK Left Fender Side Shield 14
Dome Lamp Rear of Cab 18
Driver Airbag BK Steering Wheel N/S
Driver Door Arm/Disarm Switch BK In Door 19
Driver Door Jamb Switch NAT Door Jamb 19
Driver Door Lock Motor BK In Door 19
Driver Door Window/Lock Switch BL In Door 19
Driver Heated Seat Module BL Under Seat N/S
Driver Heated Seat Switch RD Center of Instrument Panel N/S
Driver Lumbar Motor Under Seat N/S
Driver Power Seat Front Vertical Motor BK Under Seat N/S
Driver Power Seat Horizontal Motor BK Under Seat N/S
Driver Power Seat Rear Vertical Motor Under Seat N/S
Driver Power Seat Switch At Seat N/S
Driver Power Window Motor In Door 19
Duty Cycle EVAP/Purge Solenoid BK Right Fender Side Shield 17
Electric Brake Provision Bottom Left of Instrument Panel N/S
Engine Control Module (Diesel) Left Side Engine 12
Engine Coolant Temperature Sensor (Diesel) BK Left Front of Cylinder Head
(Diesel)10
Engine Coolant Temperature Sensor (Gas) BK On Thermostat Housing 3,6
Engine Oil Pressure Sensor (V6, V8) BK Near Distributor 3
Engine Oil Pressure Sensor (V10) Near Oil Filter 6
Engine Oil Pressure Sensor (Diesel) Left Side of Engine 12
Fuel Heater (Diesel) Left Side of Engine 10
Fuel Injection Pump (Diesel) Left Side of Engine, Below ECM 10
Fuel Injector No.1 BK At Fuel Injector 4,5
Fuel Injector No. 2 BK At Fuel Injector 4,5,6
Fuel Injector No. 3 BK At Fuel Injector 4,5,6
Fuel Injector No. 4 BK At Fuel Injector 4,5,6
Fuel Injector No. 5 BK At Fuel Injector 4,5,6
Fuel Injector No. 6 BK At Fuel Injector 4,5,6
Fuel Injector No. 7 BK At Fuel Injector 4,6
Fuel Injector No. 8 BK At Fuel Injector 4,6
Fuel Injector No. 9 BK At Fuel Injector 6
Fuel Injector No. 10 BK At Fuel Injector 6
Fuel Pump Module LTGY At Frame Rail 22
Fuel Transfer Pump (Diesel) Left Rear of Engine Bottom of
Pump10
BR/BE8W-90 CONNECTOR/GROUND LOCATIONS 8W - 90 - 3
CONNECTOR/GROUND LOCATIONS (Continued)

INSTALLATION...........................34
CRANKSHAFT OIL SEAL - REAR
DESCRIPTION...........................34
OPERATION.............................34
REMOVAL..............................35
INSTALLATION...........................35
DISTRIBUTOR BUSHING
REMOVAL..............................37
INSTALLATION...........................37
HYDRAULIC LIFTERS (CAM IN BLOCK)
DIAGNOSIS AND TESTING.................38
HYDRAULIC TAPPETS...................38
REMOVAL..............................39
CLEANING..............................39
INSTALLATION...........................39
PISTON & CONNECTING ROD
DESCRIPTION...........................40
STANDARD PROCEDURE..................40
PISTON FITTING.......................40
REMOVAL..............................40
CLEANING..............................41
INSPECTION............................41
INSTALLATION...........................41
PISTON RINGS
STANDARD PROCEDURE..................41
PISTON RING FITTING..................41
VIBRATION DAMPER
REMOVAL..............................42
INSTALLATION...........................42
FRONT MOUNT
REMOVAL..............................43
INSTALLATION...........................43
REAR MOUNT
REMOVAL..............................44
INSTALLATION...........................44
LUBRICATION
DESCRIPTION...........................45
OPERATION.............................45
DIAGNOSIS AND TESTING.................47
ENGINE OIL PRESSURE.................47
ENGINE OIL LEAKS.....................47
OIL
STANDARD PROCEDURE..................47
ENGINE OIL...........................47OIL FILTER
REMOVAL..............................48
INSTALLATION...........................48
OIL PAN
REMOVAL..............................48
CLEANING..............................49
INSPECTION............................49
INSTALLATION...........................49
OIL PRESSURE SENSOR/SWITCH
DESCRIPTION...........................49
OPERATION.............................49
OIL PUMP
REMOVAL..............................50
DISASSEMBLY...........................50
CLEANING..............................50
INSPECTION............................50
ASSEMBLY.............................51
INSTALLATION...........................52
INTAKE MANIFOLD
DESCRIPTION...........................52
OPERATION.............................52
DIAGNOSIS AND TESTING.................53
INTAKE MANIFOLD LEAKAGE.............53
REMOVAL..............................53
CLEANING..............................53
INSPECTION............................53
INSTALLATION...........................53
EXHAUST MANIFOLD
DESCRIPTION...........................55
OPERATION.............................55
REMOVAL..............................55
CLEANING..............................55
INSPECTION............................55
INSTALLATION...........................55
TIMING BELT / CHAIN COVER(S)
REMOVAL..............................56
INSTALLATION...........................56
TIMING BELT/CHAIN TENSIONER
DESCRIPTION...........................57
OPERATION.............................57
TIMING BELT/CHAIN AND SPROCKETS
REMOVAL..............................57
INSPECTION............................58
INSTALLATION...........................58
9 - 2 ENGINE 3.9LBR/BE

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)

CONDITION POSSIBLE CAUSES CORRECTION
4. Excessive main bearing clearance 4. Measure bearings for correct
clearance. Repair as necessary
5. Excessive end play 5. Check crankshaft thrust bearing for
excessive wear on flanges
6. Crankshaft main journal out of
round or worn6. Grind journals or replace crankshaft
7. Loose flywheel or torque converter 7. Inspect crankshaft, flexplate/flywheel
and bolts for damage. Tighten to correct
torque
LOW OIL PRESSURE 1. Low oil level 1. Check oil level and fill if necessary
2. Faulty oil pressure sending unit 2. Install new sending unit
3. Clogged oil filter 3. Install new oil filter
4. Worn oil pump 4. Replace oil pump assembly.
5. Thin or diluted oil 5. Change oil to correct viscosity.
6. Excessive bearing clearance 6. Measure bearings for correct clearance
7. Oil pump relief valve stuck 7. Remove valve to inspect, clean and
reinstall
8. Oil pump suction tube loose,
broken, bent or clogged8. Inspect suction tube and clean or
replace if necessary
9. Oil pump cover warped or cracked 9. Install new oil pump
OIL LEAKS 1. Misaligned or deteriorated gaskets 1. Replace gasket
2. Loose fastener, broken or porous
metal part2. Tighten, repair or replace the part
3. Front or rear crankshaft oil seal
leaking3. Replace seal
4. Leaking oil gallery plug or cup plug 4. Remove and reseal threaded plug.
Replace cup style plug
EXCESSIVE OIL
CONSUMPTION OR
SPARK PLUGS OIL
FOULED1. CCV System malfunction 1. (Refer to 25 - EMISSIONS CONTROL/
EVAPORATIVE EMISSIONS -
DESCRIPTION) for correct operation
2. Defective valve stem seal(s) 2. Repair or replace seal(s)
3. Worn or broken piston rings 3. Hone cylinder bores. Install new rings
4. Scuffed pistons/cylinder walls 4. Hone cylinder bores and replace
pistons as required
5. Carbon in oil control ring groove 5. Remove rings and de-carbon piston
6. Worn valve guides 6. Inspect/replace valve guides as
necessary
7. Piston rings fitted too tightly in
grooves7. Remove rings and check ring end gap
and side clearance. Replace if necessary
BR/BEENGINE 3.9L 9 - 7
ENGINE 3.9L (Continued)