engine DODGE RAM 2001 Service Repair Manual

NOTE: If the PDC is being replaced with a new unit,
be certain to transfer each of the blade-type fuses,
cartridge fuses and relays from the faulty PDC to
the proper cavities of the replacement PDC. Refer
to Power Distribution in the index of this service
manual for the location of complete PDC circuit dia-
grams and cavity assignments.(1) Position the PDC and the headlamp and dash
wire harness unit in the engine compartment.
(2) Install and tighten the two screws that secure
the PDC housing to the left front fender inner shield.
Tighten the screws to 8.4 N´m (75 in. lbs.).
(3) Install and tighten the screw that secures the
PDC housing to the left front fender wheel housing.
Tighten the screw to 2.2 N´m (20 in. lbs.).
(4) Install the eyelet of the battery positive cable
PDC take out onto the forward B(+) terminal stud in
the PDC.
(5) Install and tighten the nut that secures the
eyelet of the battery positive cable PDC take out to
the forward B(+) terminal stud in the PDC. Tighten
the nut to 8.4 N´m (75 in. lbs.).
(6) Install the eyelet of the battery negative cable
generator output take out onto the rearward B(+) ter-
minal stud in the PDC.
(7) Install and tighten the nut that secures the
eyelet of the battery negative cable generator output
take out to the rearward B(+) terminal stud in the
PDC. Tighten the nut to 75 in. lbs.
(8) Reconnect the engine wire harness in-line con-
nector to the PDC.
(9) Install and tighten the screw that secures the
engine wire harness in-line connector to the PDC.
Tighten the screw until a distinct audible click is
heard.
(10) Install and latch the cover onto the PDC.
(11) Engage each of the retainers that secure the
headlamp and dash wire harness to the vehicle body
and chassis components. Refer toConnector Loca-
tionsin the index of this service manual for the loca-
tion of more information on the headlamp and dash
wire harness retainer locations.
(12) Install all of the fasteners that secure each of
the headlamp and dash wire harness ground eyelets
to the vehicle body and chassis components. Refer to
Connector Locationsin the index of this service
manual for the location of more information on the
ground eyelet locations.
(13) Reconnect each of the headlamp and dash
wire harness connectors. Refer toConnector Loca-
tionsin the index of this service manual for the loca-
tion of more information on the headlamp and dash
wire harness connector locations.
(14) Reconnect the battery negative cable.POWER OUTLET
DESCRIPTION
An accessory power outlet is standard equipment
on this model. The power outlet is installed in the
instrument panel below the cigar lighter and next to
the ash receiver, which is located near the center of
Fig. 9 Battery and Generator Connections to PDC
1 - NUTS
2 - BATTERY POSITIVE CABLE
3 - BATTERY NEGATIVE CABLE
4 - POWER DISTRIBUTION CENTER
5 - CABLE EYELETS
Fig. 10 Power Distribution Center
1 - FENDER INNER SHIELD
2 - INNER WHEEL HOUSE
3 - SCREW
4 - SCREW
5 - POWER DISTRIBUTION CENTER
BR/BE8W-97 POWER DISTRIBUTION 8W - 97 - 9
POWER DISTRIBUTION CENTER (Continued)

ENGINE
TABLE OF CONTENTS
page page
ENGINE 3.9L.............................. 1
ENGINE 5.2L............................. 59
ENGINE 5.9L............................ 116ENGINE 8.0L............................ 171
ENGINE 5.9L DIESEL..................... 229
ENGINE 3.9L
TABLE OF CONTENTS
page page
ENGINE 3.9L
DESCRIPTION............................3
DIAGNOSIS AND TESTING..................3
ENGINE DIAGNOSIS - INTRODUCTION.......3
PERFORMANCE........................4
MECHANICAL..........................6
LUBRICATION..........................8
CYLINDER COMPRESSION PRESSURE......9
CYLINDER COMBUSTION PRESSURE
LEAKAGE..............................9
REAR SEAL AREA LEAKS................10
STANDARD PROCEDURE..................10
CYLINDER BORE HONING...............10
HYDROSTATIC LOCK....................11
REPAIR DAMAGED OR WORN THREADS....11
FORM-IN-PLACE GASKETS AND SEALERS . . . 11
REMOVAL..............................12
INSTALLATION...........................13
SPECIFICATIONS........................14
SPECIAL TOOLS.........................19
AIR CLEANER ELEMENT
REMOVAL..............................21
INSTALLATION...........................21
CYLINDER HEAD
DESCRIPTION...........................22
OPERATION.............................22
DIAGNOSIS AND TESTING.................22
CYLINDER HEAD GASKET FAILURE........22
REMOVAL..............................23
CLEANING..............................23
INSPECTION............................23
INSTALLATION...........................23
CYLINDER HEAD COVER(S)
REMOVAL..............................24
CLEANING..............................24INSPECTION............................24
INSTALLATION...........................24
INTAKE/EXHAUST VALVES & SEATS
DESCRIPTION...........................25
STANDARD PROCEDURE..................25
VALVES, GUIDES AND SPRINGS...........25
REMOVAL..............................27
CLEANING..............................27
INSPECTION............................27
INSTALLATION...........................28
ENGINE BLOCK
CLEANING..............................28
INSPECTION............................28
CAMSHAFT & BEARINGS (IN BLOCK)
REMOVAL..............................29
INSTALLATION...........................29
CONNECTING ROD BEARINGS
STANDARD PROCEDURE..................31
CONNECTING ROD BEARING FITTING......31
CRANKSHAFT
DESCRIPTION...........................31
OPERATION.............................31
REMOVAL..............................31
INSTALLATION...........................32
CRANKSHAFT MAIN BEARINGS
DESCRIPTION...........................32
OPERATION.............................32
STANDARD PROCEDURE..................33
MAIN BEARING FITTING.................33
REMOVAL..............................33
INSTALLATION...........................34
CRANKSHAFT OIL SEAL - FRONT
DESCRIPTION...........................34
OPERATION.............................34
REMOVAL..............................34
BR/BEENGINE 9 - 1

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)

DIAGNOSIS AND TESTINGÐPERFORMANCE
PERFORMANCE DIAGNOSIS CHARTÐGASOLINE ENGINES
CONDITION POSSIBLE CAUSES CORRECTION
ENGINE WILL NOT
CRANK1. Weak or dead battery 1. Charge/Replace Battery. (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM/
BATTERY - STANDARD PROCEDURE).
Check charging system. (Refer to 8 -
ELECTRICAL/CHARGING - DIAGNOSIS
AND TESTING).
2. Corroded or loose battery
connections2. Clean/tighten suspect battery/starter
connections
3. Faulty starter or related circuit(s) 3. Check starting system. (Refer to 8 -
ELECTRICAL/STARTING - DIAGNOSIS
AND TESTING)
4. Seized accessory drive component 4. Remove accessory drive belt and
attempt to start engine. If engine starts,
repair/replace seized component.
5. Engine internal mechanical failure or
hydro-static lock5. Refer to (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
ENGINE CRANKS BUT
WILL NOT START1. No spark 1. Check for spark. (Refer to 8 -
ELECTRICAL/IGNITION CONTROL -
DESCRIPTION)
2. No fuel 2. Perform fuel pressure test, and if
necessary, inspect fuel injector(s) and
driver circuits. (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY/FUEL PUMP
- DIAGNOSIS AND TESTING).
3. Low or no engine compression 3. Perform cylinder compression pressure
test. (Refer to 9 - ENGINE - DIAGNOSIS
AND TESTING).
ENGINE LOSS OF
POWER1. Worn or burned distributor rotor 1. Install new distributor rotor
2. Worn distributor shaft 2. Remove and repair distributor (Refer to
8 - ELECTRICAL/IGNITION CONTROL/
DISTRIBUTOR - REMOVAL).
3. Worn or incorrect gapped spark
plugs3. Clean plugs and set gap. (Refer to 8 -
ELECTRICAL/IGNITION CONTROL/
SPARK PLUG - CLEANING).
4. Dirt or water in fuel system 4. Clean system and replace fuel filter
5. Faulty fuel pump 5. Install new fuel pump
6. Incorrect valve timing 6. Correct valve timing
7. Blown cylinder head gasket 7. Install new cylinder head gasket
8. Low compression 8. Test cylinder compression (Refer to 9 -
ENGINE - DIAGNOSIS AND TESTING).
9. Burned, warped, or pitted valves 9. Install/Reface valves as necessary
10. Plugged or restricted exhaust
system10. Install new parts as necessary
9 - 4 ENGINE 3.9LBR/BE
ENGINE 3.9L (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
11. Faulty ignition cables 11. Replace any cracked or shorted
cables
12. Faulty ignition coil 12. Test and replace, as necessary (Refer
to 8 - ELECTRICAL/IGNITION
CONTROL/IGNITION COIL - REMOVAL).
ENGINE STALLS OR
ROUGH IDLE1. Carbon build-up on throttle plate 1. Remove throttle body and de-carbon.
(Refer to 14 - FUEL SYSTEM/FUEL
INJECTION/THROTTLE BODY -
REMOVAL).
2. Engine idle speed too low 2. Check Idle Air Control circuit. (Refer to
14 - FUEL SYSTEM/FUEL INJECTION/
IDLE AIR CONTROL MOTOR -
DESCRIPTION)
3. Worn or incorrectly gapped spark
plugs3. Replace or clean and re-gap spark
plugs (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG -
CLEANING)
4. Worn or burned distributor rotor 4. Install new distributor rotor
5. Spark plug cables defective or
crossed5. Check for correct firing order or
replace spark plug cables. (Refer to 8 -
ELECTRICAL/IGNITION CONTROL/
SPARK PLUG CABLE - DIAGNOSIS
AND TESTING)
6. Faulty coil 6. Test and replace, if necessary (Refer
to 8 - ELECTRICAL/IGNITION
CONTROL/IGNITION COIL - REMOVAL)
7. Intake manifold vacuum leak 7. Inspect intake manifold gasket and
vacuum hoses (Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD -
DIAGNOSIS AND TESTING).
ENGINE MISSES ON
ACCELERATION1. Worn or incorrectly gapped spark
plugs1. Replace spark plugs or clean and set
gap. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG -
CLEANING)
2. Spark plug cables defective or
crossed2. Replace or rewire secondary ignition
cables. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG
CABLE - REMOVAL)
3. Dirt in fuel system 3. Clean fuel system
4. Burned, warped or pitted valves 4. Install new valves
5. Faulty coil 5. Test and replace as necessary (Refer
to 8 - ELECTRICAL/IGNITION
CONTROL/IGNITION COIL - REMOVAL)
BR/BEENGINE 3.9L 9 - 5
ENGINE 3.9L (Continued)

DIAGNOSIS AND TESTINGÐ MECHANICAL
ENGINE MECHANICAL DIAGNOSIS CHART
CONDITION POSSIBLE CAUSES CORRECTION
NOISY VALVES/LIFTERS 1. High or low oil level in crankcase 1. Check for correct oil level. Adjust oil
level by draining or adding as needed
2. Thin or diluted oil 2. Change oil. (Refer to 9 - ENGINE/
LUBRICATION/OIL - STANDARD
PROCEDURE)
3. Low oil pressure 3. Check engine oil level. If ok, Perform
oil pressure test. (Refer to 9 - ENGINE/
LUBRICATION - DIAGNOSIS AND
TESTING) for engine oil pressure
test/specifications
4. Dirt in tappets/lash adjusters 4. Clean/replace hydraulic tappets/lash
adjusters
5. Bent push rod(s) 5. Install new push rods
6. Worn rocker arms 6. Inspect oil supply to rocker arms and
replace worn arms as needed
7. Worn tappets/lash adjusters 7. Install new hydraulic tappets/lash
adjusters
8. Worn valve guides 8. Inspect all valve guides and replace as
necessary
9. Excessive runout of valve seats or
valve faces9. Grind valves and seats
CONNECTING ROD
NOISE1. Insufficient oil supply 1. Check engine oil level.
2. Low oil pressure 2. Check engine oil level. If ok, Perform
oil pressure test. (Refer to 9 - ENGINE/
LUBRICATION - DIAGNOSIS AND
TESTING) engine oil pressure test/
specifications
3. Thin or diluted oil 3. Change oil to correct viscosity. (Refer
to 9 - ENGINE/LUBRICATION/OIL -
STANDARD PROCEDURE) for correct
procedure/engine oil specifications
4. Excessive connecting rod bearing
clearanceMeasure bearings for correct clearance
with plasti-gage. Repair as necessary
5. Connecting rod journal out of round 5. Replace crankshaft or grind journals
6. Misaligned connecting rods 6. Replace bent connecting rods
MAIN BEARING NOISE 1. Insufficient oil supply 1. Check engine oil level.
2. Low oil pressure 2. Check engine oil level. If ok, Perform
oil pressure test. (Refer to 9 - ENGINE/
LUBRICATION - DIAGNOSIS AND
TESTING)
3. Thin or diluted oil 3. Change oil to correct viscosity.
9 - 6 ENGINE 3.9LBR/BE
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)

DIAGNOSIS AND TESTINGÐLUBRICATION
CONDITION POSSIBLE CAUSES CORRECTION
OIL LEAKS 1. Gaskets and O-Rings. 1.
(a) Misaligned or damaged. (a) Replace as necessary.
(b) Loose fasteners, broken or
porous metal parts.(b) Tighten fasteners, Repair or
replace metal parts.
2. Crankshaft rear seal 2. Replace as necessary.
3. Crankshaft seal flange.
Scratched, nicked or grooved.3. Polish or replace crankshaft.
4. Oil pan flange cracked. 4. Replace oil pan.
5. Timing chain cover seal,
damaged or misaligned.5. Replace seal.
6. Scratched or damaged vibration
damper hub.6. Polish or replace damper.
OIL PRESSURE DROP 1. Low oil level. 1. Check and correct oil level.
2. Faulty oil pressure sending unit. 2. Replace sending unit.
3. Low oil pressure. 3. Check pump and bearing
clearance.
4. Clogged oil filter. 4. Replace oil filter.
5. Worn oil pump. 5. Replace as necessary.
6. Thin or diluted oil. 6. Change oil and filter.
7. Excessive bearing clearance. 7. Replace as necessary.
8. Oil pump relief valve stuck. 8. Clean or replace relief valve.
9. Oil pump suction tube loose or
damaged.9. Replace as necessary.
OIL PUMPING AT RINGS; SPARK
PLUGS FOULING1. Worn or damaged rings. 1. Hone cylinder bores and replace
rings.
2. Carbon in oil ring slots. 2. Replace rings.
3. Incorrect ring size installed. 3. Replace rings.
4. Worn valve guides. 4. Ream guides and replace valves.
5. Leaking intake gasket. 5. Replace intake gaskets.
6. Leaking valve guide seals. 6. Replace valve guide seals.
9 - 8 ENGINE 3.9LBR/BE
ENGINE 3.9L (Continued)

DIAGNOSIS AND TESTINGÐCYLINDER
COMPRESSION PRESSURE
The results of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise, the indicated compression pressures may
not be valid for diagnosis purposes.
(1) Clean the spark plug recesses with compressed
air.
(2) Remove the spark plugs (Refer to 8 - ELEC-
TRICAL/IGNITION CONTROL/SPARK PLUG -
REMOVAL).
(3) Secure the throttle in the wide-open position.
(4) Disconnect the ignition coil.
(5) Insert a compression pressure gauge and rotate
the engine with the engine starter motor for three
revolutions.
(6) Record the compression pressure on the third
revolution. Continue the test for the remaining cylin-
ders.
(Refer to 9 - ENGINE - SPECIFICATIONS) for the
correct engine compression pressures.
DIAGNOSIS AND TESTINGÐCYLINDER
COMBUSTION PRESSURE LEAKAGE
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
²Exhaust and intake valve leaks (improper seat-
ing)
²Leaks between adjacent cylinders or into water
jacket²Any causes for combustion/compression pressure
loss
WARNING: DO NOT REMOVE THE RADIATOR CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE.
SERIOUS BURNS FROM HOT COOLANT CAN
OCCUR.
Check the coolant level and fill as required. DO
NOT install the radiator cap.
Start and operate the engine until it attains nor-
mal operating temperature, then turn OFF the
engine.
Remove the spark plugs.
Remove the oil filler cap.
Remove the air cleaner.
Calibrate the tester according to the manufactur-
er's instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1,379
kPa (200 psi) maximum and 552 kPa (80 psi) recom-
mended.
Perform the test procedure on each cylinder accord-
ing to the tester manufacturer's instructions. While
testing, listen for pressurized air escaping through
the throttle body, tailpipe or oil filler cap opening.
Check for bubbles in the radiator coolant.
All gauge pressure indications should be equal,
with no more than 25% leakage.
FOR EXAMPLE:At 552 kPa (80 psi) input pres-
sure, a minimum of 414 kPa (60 psi) should be main-
tained in the cylinder.
Refer to CYLINDER COMBUSTION PRESSURE
LEAKAGE DIAGNOSIS CHART below
CYLINDER COMBUSTION PRESSURE LEAKAGE DIAGNOSIS CHART
CONDITION POSSIBLE CAUSE CORRECTION
AIR ESCAPES THROUGH
THROTTLE BODYIntake valve bent, burnt, or not
seated properlyInspect valve and valve seat.
Reface or replace, as necessary
AIR ESCAPES THROUGH
TAILPIPEExhaust valve bent, burnt, or not
seated properlyInspect valve and valve seat.
Reface or replace, as necessary
AIR ESCAPES THROUGH
RADIATORHead gasket leaking or cracked
cylinder head or blockRemove cylinder head and inspect.
Replace defective part
MORE THAN 50% LEAKAGE
FROM ADJACENT CYLINDERSHead gasket leaking or crack in
cylinder head or block between
adjacent cylindersRemove cylinder head and inspect.
Replace gasket, head, or block as
necessary
MORE THAN 25% LEAKAGE AND
AIR ESCAPES THROUGH OIL
FILLER CAP OPENING ONLYStuck or broken piston rings;
cracked piston; worn rings and/or
cylinder wallInspect for broken rings or piston.
Measure ring gap and cylinder
diameter, taper and out-of-round.
Replace defective part as necessary
BR/BEENGINE 3.9L 9 - 9
ENGINE 3.9L (Continued)