fuel CHRYSLER CARAVAN 2005 Owners Manual

(9) Raise vehicle.
(10) Attach wiring harness support clip to the
engine oil dipstick tube.
(11) Connect oil pressure switch electrical connec-
tor.
(12) Install the A/C compressor.
(13) Install the water pump pulley.
(14) Connect the radiator lower hose.
(15) Install the accessory drive belt and splash
shield (Refer to 7 - COOLING/ACCESSORY DRIVE/
DRIVE BELTS - INSTALLATION).(16) Connect the engine block heater electrical con-
nector (if equipped).
(17) Connect the knock sensor electrical connector
(3.8L only).
(18) Install the torque converter to flex plate bolts.
(19) Install the transaxle case cover (Fig. 8).
(20) Install the powertrain struts (Fig. 8).
(21) Install the engine rear mount bracket.
(22) Install the engine front mount and bracket
assembly.
(23)AWD equipped;Install the power transfer
unit (PTU) (Refer to 21 - TRANSMISSION/TRANS-
AXLE/POWER TRANSFER UNIT - INSTALLA-
TION).
(24) Install the axle shafts (Refer to 3 - DIFFER-
ENTIAL & DRIVELINE/HALF SHAFT - INSTALLA-
TION).
(25) Connect exhaust pipe to manifold (Fig. 7).
(26) Install crossmember cradle plate (Fig. 6).
(27) Lower vehicle.
(28) Connect transaxle shift linkage.
(29) Connect transaxle electrical connectors.
(30) Remove plugs from transmission cooler hoses
and install transaxle oil cooler line service splice kit.
Refer to instructions included with kit.
(31) Install transaxle dipstick tube and attach
electrical harness clip.
(32) Connect the A/C lines to compressor.
(33) Connect the A/C compressor electrical connec-
tor.
(34) Evacuate and recharge A/C system.
(35) Connect crankshaft and camshaft position
sensors.
(36) Connect the fuel injector electrical harness
connector and engage clip to support bracket.
(37) Connect engine coolant temperature (ECT)
sensor and ignition coil electrical connectors.
(38) Connect the ground strap to rear of cylinder
head.
(39) Install power steering reservoir.
(40) Engage wire harness clip to engine right side
mount.
(41) Connect the brake booster and speed control
vacuum hoses.
(42) Connect the vacuum hoses to the throttle
body.
(43) Connect the EGR transducer electrical connec-
tor (if equipped).
(44) Connect the TPS, IAC, and MAP sensor elec-
trical connectors.
(45) Connect throttle cables to throttle body.
(46) Install the radiator fans (Refer to 7 - COOL-
ING/ENGINE/RADIATOR FAN - INSTALLATION).
(47) Connect the radiator upper hose.
(48) Connect the heater hoses. Remove pinch-off
pliers from the rear heater hoses (if equipped).
Fig. 13 Right Mount to Engine
1 - BOLT
2 - MOUNT BRACKET
3 - ENGINE RIGHT MOUNT ASSEMBLY
Fig. 14 LEFT MOUNT TO FRAME BRACKET
1 - FRAME BRACKET
2 - FRAME RAIL - LEFT
3 - BOLT
4 - TRANSAXLE MOUNT
9 - 92 ENGINE 3.3/3.8LRS
ENGINE 3.3/3.8L (Continued)

(49) Install the radiator upper support crossmem-
ber (Refer to 23 - BODY/EXTERIOR/GRILLE OPEN-
ING REINFORCEMENT - INSTALLATION).
(50) Install the wiper module (Refer to 8 - ELEC-
TRICAL/WIPERS/WASHERS/WIPER MODULE -
INSTALLATION).
(51) Connect the fuel line to fuel rail (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY/FUEL LINES -
STANDARD PROCEDURE).
(52) Install the air cleaner and hoses.
(53) Install new oil filter. Fill engine crankcase
with proper oil to correct level.
(54) Connect negative cable to battery.
(55) Fill the cooling system (Refer to 7 - COOLING
- STANDARD PROCEDURE).
(56) Start engine and run until operating temper-
ature is reached.
(57) Adjust transmission linkage, if necessary.
SPECIFICATIONS
3.3/3.8L ENGINE
GENERAL DESCRIPTION
DESCRIPTION SPECIFICATION
Metric Standard
Engine Type 60É V-6 Engine
Number of
Cylinders6
Displacement
3.3L3.3Liters 201 cu.in.
Displacement
3.8L3.8 Liters 231 cu. in.
Bore 3.3L 93.0 mm 201 cu.in.
Bore 3.8L 96.0 mm 3.779 cu.in.
Stroke 3.3L 81 mm 3.188 in.
Stroke 87 mm 3.425 in.
Compression
Ratio 3.3L- 9.35:1
Compression
Ratio 3.8L- 9.6:1
Firing Order - 1-2-3-4-5-6
Compression
Pressure-
Minimum689.5 kPa 100 psi.
Cylinder
Compression
(Max. Difference
Between
Cylinders- 25%
CYLINDER BLOCK
DESCRIPTION SPECIFICATION
Metric Standard
Cylinder Bore
Diameter
(Standard) 3.3L92.993-93.007
mm3.661-3.6617 in.
Cylinder Bore
Diameter
(Standard) 3.8L95.993-96.007
mm3.7792-3.780 in.
Out of Round
(Service Limits)0.076 mm 0.003 in.
Taper (Service
Limits)0.051 mm 0.002 in.
Lifter Bore
Diameter22.980-23.010
mm0.905-0.906 in.
Deck Surface
Flatness (Max.)0.1 mm 0.004 in.
CRANKSHAFT
DESCRIPTION SPECIFICATION
Metric Standard
Connecting Rod
Journal
Diameter57.979-58.005
mm2.2827-2.2837
in.
Main Bearing
Journal
Diameter63.993-64.013
mm2.5194-2.5202
in.
Journal
Out-of-Round
(Max.)0.025 mm 0.001 in.
Journal Taper
(Max.)0.025 mm 0.001 in
End Play 0.09-0.24 mm 0.0036-0.0095
in.
Wear Limit 0.381 mm 0.015 in.
Main Bearing
Diametrical
Clearance
1-2-3-40.011-0.055
mm0.0005-0.0022
in.
Wear Limit 0.076 mm 0.003 in.
RSENGINE 3.3/3.8L9-93
ENGINE 3.3/3.8L (Continued)

(2) Disconnect the inlet air temperature sensor
(Fig. 16).
(3) Remove the inlet hose to throttle body.
(4) Remove the bolt for air box at upper radiator
cross member.
(5) Pull air box up and off over the single locating
pin.
(6) Remove air box from vehicle
INSTALLATION
(1) Install air box into vehicle and onto the locat-
ing pin.
(2) Install bolt to hold air box to the upper radia-
tor cross member.
(3) Install the inlet hose to the throttle body.
(4) Connect the inlet air temperature sensor (Fig.
16).
(5) Connect the negative battery cable.
CYLINDER HEAD
DESCRIPTION
The aluminum cylinder heads (Fig. 17) are
designed to create high flow combustion chambers to
improve performance, while minimizing the change
to the burn rate in the chamber. The cylinder head
incorporates the combustion chamber. Two valves
per-cylinder are used with inserted valve seats and
guides. A multi-layer steel (MLS) type gasket is used
between the cylinder head and engine block.
DIAGNOSIS AND TESTINGÐCYLINDER HEAD
GASKET
A cylinder head gasket leak can be located between
adjacent cylinders or between a cylinder and the
adjacent water jacket.
Possible indications of the cylinder head gasket
leaking between adjacent cylinders are:
²Loss of engine power
²Engine misfiring
²Poor fuel economy
Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
²Engine overheating
²Loss of coolant
²Excessive steam (white smoke) emitting from
exhaust
²Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test (Refer
to 9 - ENGINE - DIAGNOSIS AND TESTING). An
engine cylinder head gasket leaking between adja-
cent cylinders will result in approximately a 50±70%
reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING WITH COOLANT PRES-
SURE CAP REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure
cap. Start the engine and allow it to warm up until
thermostat opens.
If a large combustion/compression pressure leak
exists, bubbles will be visible in the coolant.
COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE PRESSURE BUILT UP, BY CONTINUOUS
ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to
pressure cap neck. Start the engine and observe the
tester's pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.
Fig. 16 Inlet Air Temperature Sensor
9 - 102 ENGINE 3.3/3.8LRS
AIR CLEANER HOUSING (Continued)

OIL
STANDARD PROCEDURE
STANDARD PROCEDURE - ENGINE OIL AND
FILTER CHANGE
Change engine oil at mileage and time intervals
described in the Maintenance Schedule. (Refer to
LUBRICATION & MAINTENANCE/MAINTE-
NANCE SCHEDULES - DESCRIPTION)
WARNING: NEW OR USED ENGINE OIL CAN BE
IRRITATING TO THE SKIN. AVOID PROLONGED OR
REPEATED SKIN CONTACT WITH ENGINE OIL.
CONTAMINANTS IN USED ENGINE OIL, CAUSED BY
INTERNAL COMBUSTION, CAN BE HAZARDOUS TO
YOUR HEALTH. THOROUGHLY WASH EXPOSED
SKIN WITH SOAP AND WATER. DO NOT WASH
SKIN WITH GASOLINE, DIESEL FUEL, THINNER, OR
SOLVENTS, HEALTH PROBLEMS CAN RESULT. DO
NOT POLLUTE, DISPOSE OF USED ENGINE OIL
PROPERLY. CONTACT YOUR DEALER OR GOVERN-
MENT AGENCY FOR LOCATION OF COLLECTION
CENTER IN YOUR AREA.Run engine until achieving normal operating tem-
perature.
(1) Position the vehicle on a level surface and turn
engine off.
(2) Open hood, remove oil fill cap (Fig. 97).
(3) Hoist and support vehicle on safety stands.
Refer to Hoisting and Jacking Recommendations.
(Refer to LUBRICATION & MAINTENANCE/HOIST-
ING - STANDARD PROCEDURE)
(4) Place a suitable drain pan under crankcase
drain (Fig. 96).
(5) Remove drain plug from crankcase (Fig. 96)
and allow oil to drain into pan. Inspect drain plug
threads for stretching or other damage. Replace
drain plug and gasket if damaged.
(6) Remove oil filter. (Refer to 9 - ENGINE/LUBRI-
CATION/OIL FILTER - REMOVAL)
(7) Install and tighten drain plug in crankcase.
(8) Install new oil filter. (Refer to 9 - ENGINE/LU-
BRICATION/OIL FILTER - INSTALLATION)
(9) Lower vehicle and fill crankcase with specified
type and amount of engine oil. (Refer to LUBRICA-
TION & MAINTENANCE/FLUID TYPES -
DESCRIPTION)
(10) Install oil fill cap.
Fig. 95 Engine Oiling System
1 - OIL SUPPLY FOR BALL SOCKET THROUGH PUSH ROD 7 - OUTER ROTOR
2 - OIL SUPPLY PASSAGE FROM SHAFT TO ROCKER ARM 8 - INNER ROTOR
3 - ROCKER SHAFT 9 - RELIEF VALVE
4 - OIL FLOWS TO ONLY ONE PEDASTAL ON EACH HEAD; THIRD
FROM REAR ON RIGHT HEAD, THIRD FROM FRONT ON LEFT
HEAD10 - OIL PAN
5 - ROCKER SHAFT TOWER 11 - OIL SCREEN
6 - CRANKSHAFT 12 - OIL PUMP CASE
RSENGINE 3.3/3.8L9 - 139
LUBRICATION (Continued)

STANDARD PROCEDURE - INTAKE MANIFOLD
VACUUM PORT REPAIR
The composite intake manifold vacuum ports can
be repaired. Although, if the manifold plenum cham-
ber is damaged or cracked, the manifold must be
replaced.
To repair a broken or damaged vacuum nipple
(port) on the composite intake manifold, perform the
following procedure:
PARTS REQUIRED TOOLS REQUIRED
´ Brass Nipple ± 1/49
O.D. x 1/89pipe thread
(LDP/Speed Control Port)´ Pipe Tap ± 1/89-18
NPT
´ Drill Bit ± 11/329
´ File/Sandpaper
´ Brass Nipple ± 1/29
O.D. x 1/49pipe thread
(Brake Booster Port)´ Pipe Tap ± 1/49-18
NPT
´ Drill Bit ± 7/169
´ File/Sandpaper
NOTE: While performing this procedure, avoid get-
ting the manifold material residue into the plenum
chamber.
(1) File or sand the remaining port back until a
flat surface is obtained (plane normal to nipple (port)
axis).
(2) Drill out the nipple (port) base using a 7/16º
(brake booster port) or 11/32º (LDP/speed control port
) drill bit (Fig. 114).
(3) Using a 1/4º±18 NPT (brake booster port) or
1/8º±18 NPT (LDP/speed control port ) pipe tap, cut
internal threads (Fig. 114). Use caution to start tap
in a axis same as original nipple.
(4) Apply MopartThread Sealant to threads of
repair nipple(s).
(5) Install repair nipple(s). Do not over torque
repair nipple(s).
REMOVAL - UPPER INTAKE MANIFOLD
(1) Disconnect battery negative cable.
(2) Disconnect inlet air temperature (IAT) sensor
electrical connector.
(3) Remove air inlet resonator to throttle body
hose assembly.
(4) Disconnect throttle and speed control cables
from throttle body (Refer to 14 - FUEL SYSTEM/
FUEL INJECTION/THROTTLE CONTROL CABLE -
REMOVAL).
(5) Disconnect make-up air hose support clip from
throttle cable bracket.(6) Disconnect the automatic idle speed (AIS)
motor and throttle position sensor (TPS) wiring con-
nectors from throttle body.
(7) Disconnect the manifold absolute pressure
(MAP) sensor electrical connector.
(8) Disconnect the vapor purge vacuum hose from
throttle body.
(9) Disconnect the PCV hose (Fig. 115).
(10) Remove the power steering reservoir attach-
ing bolts and only loosen the nut (Fig. 116). Lift res-
ervoir up to disengage lower mount from stud. Set
reservoir aside.Do notdisconnect hose.
(11) Disconnect the brake booster and leak detec-
tion pump (LDP) hoses from intake manifold (Fig.
117).
(12) Remove intake manifold bolts and remove the
manifold (Fig. 118).
(13) Cover the lower intake manifold with a suit-
able cover while the upper manifold is removed.
(14) Clean and inspect the upper intake manifold
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - CLEANING) and (Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - INSPECTION).
CLEANING
(1) Discard gasket(s).
(2) Clean all sealing surfaces.
Fig. 114 Intake Manifold Port Repair
1 - BRAKE BOOSTER PORT = 1/49±18 NPT PIPE TAP
1 - LDP/SPEED CONTROL PORT = 1/89±18 NPT PIPE TAP
2 - DRILL BIT = 7/169BRAKE BOOSTER PORT
2 - DRILL BIT = 11/329LDP/SPEED CONTROL PORT
3 - INTAKE MANIFOLD
9 - 148 ENGINE 3.3/3.8LRS
INTAKE MANIFOLD - UPPER (Continued)

(5) Connect the MAP sensor electrical connector.
(6) Connect the brake booster and LDP vacuum
hose to intake manifold (Fig. 117).CAUTION: The special screws used for attaching
the EGR tube and power steering reservoir to the
manifold must be installed slowly using hand tools
only. This requirement is to prevent the melting of
material that causes stripped threads. If threads
become stripped, an oversize repair screw is avail-
able. For more information and procedure (Refer to
9 - ENGINE/MANIFOLDS/INTAKE MANIFOLD - STAN-
DARD PROCEDURE - MANIFOLD STRIPPED
THREAD REPAIR).
(7) Install the power steering reservoir (Fig. 116).
Tighten screws to manifold to 5.6 N´m (50 in. lbs.).
(8) Connect throttle and speed control cables to
throttle body (Refer to 14 - FUEL SYSTEM/FUEL
INJECTION/THROTTLE CONTROL CABLE -
INSTALLATION)
(9) Attach make up air hose clip into the hole in
the throttle cable bracket.
(10) Connect the wiring connectors to the throttle
position sensor (TPS) and Automatic Idle Speed (AIS)
motor.
(11) Install air cleaner and air inlet hose assembly.
(12) Connect the inlet air temperature (IAT) sen-
sor electrical connector.
(13) Connect battery negative cable.
INTAKE MANIFOLD - LOWER
REMOVAL - LOWER INTAKE MANIFOLD
(1) Perform fuel system pressure release procedure
(before attempting any repairs).(Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY - STANDARD
PROCEDURE)
(2) Drain the cooling system. (Refer to 7 - COOL-
ING - STANDARD PROCEDURE)
(3) Remove the upper intake manifold. (Refer to 9
- ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL)
(4) Remove the fuel line. (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/FUEL LINES - STANDARD
PROCEDURE) (Refer to 14 - FUEL SYSTEM/FUEL
DELIVERY/QUICK CONNECT FITTING - STAN-
DARD PROCEDURE)
(5) Remove ignition coil and bracket (Fig. 120).
(6) Disconnect heater supply hose and engine cool-
ant temperature sensor (Fig. 121).
(7) Disconnect the fuel injector wire harness.
(8) Remove the fuel injectors and rail assembly
(Fig. 120).
(9) Remove radiator upper hose.
(10) Remove the intake manifold bolts.
(11) Remove lower intake manifold (Fig. 122).
Fig. 118 INTAKE MANIFOLD - UPPER
1 - BOLT
2 - MAP SENSOR
3 - SCREW
4 - MANIFOLD - UPPER
5 - WIRE HARNESS
6 - GASKET (3 PER CYL. BANK)
Fig. 119 UPPER MANIFOLD TIGHTENING
SEQUENCE
9 - 150 ENGINE 3.3/3.8LRS
INTAKE MANIFOLD - UPPER (Continued)

WARNING: INTAKE MANIFOLD GASKET IS MADE
OF VERY THIN METAL AND MAY CAUSE PER-
SONAL INJURY, HANDLE WITH CARE.
(12) Remove intake manifold seal retainers screws
(Fig. 122). Remove intake manifold gasket.
(13) Inspect and clean manifold. (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSPECTION) (Refer to 9 - ENGINE/MANIFOLDS/
INTAKE MANIFOLD - CLEANING)
CLEANING
(1) Discard gasket(s).
(2) Clean all sealing surfaces.
INSPECTION
Check for:
²Damage and cracks of each section.
²Clogged water passages in end cross-overs (if
equipped).²Check for cylinder head mounting surface distor-
tion using a straightedge and thickness gauge. (Refer
to 9 - ENGINE/CYLINDER HEAD - INSPECTION)
INSTALLATION - LOWER INTAKE MANIFOLD
(1) Place a bead (approximately 1/4 in. diameter)
of MopartEngine RTV GEN II onto each of thefour
manifold to cylinder head gasket corners (Fig. 123).
(2) Carefully install the new intake manifold gas-
ket (Fig. 122). Tighten end seal retainer screws to 12
N´m (105 in. lbs.).
(3) Install lower intake manifold (Fig. 122). Install
the bolts and torque to 1 N´m (10 in. lbs.). Then
torque bolts to 22 N´m (200 in. lbs.) in sequence
shown in (Fig. 124). Then torque again to 22 N´m
(200 in. lbs.). After intake manifold is in place,
inspect to make sure seals are in place.
(4) Install the fuel injectors and rail assembly.
(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY/
FUEL RAIL - INSTALLATION)
(5) Connect fuel injector electrical harness.
(6) Connect the engine coolant temperature sensor
(Fig. 121).
(7) Connect the heater supply (Fig. 121) and radi-
ator upper hoses to manifold.
(8) Connect the fuel line. (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/QUICK CONNECT FIT-
TING - STANDARD PROCEDURE)
Fig. 120 FUEL RAIL AND IGNITION COIL &
BRACKET
1 - FUEL RAIL
2 - BOLT - FUEL RAIL
3 - NUT - IGNITION COIL
4 - BOLT - IGNITION COIL
5 - IGNITION COIL
6 - BRACKET - IGNITION COIL
7 - STUD - IGNITION COIL
8 - SEPARATOR - SPARK PLUG CABLE
9 - BRACKET - SPARK PLUG CABLE SEPARATOR
10 - BOLT - SEPARATOR BRACKET
11 - BRACKET - SPARK PLUG CABLE SEPARATOR
Fig. 121 ECT SENSOR & HEATER SUPPLY
1 - ENGINE COOLANT TEMPERATURE SENSOR
2 - CONNECTOR - ENGINE COOLANT SENSOR
3 - FITTING - HEATER SUPPLY
RSENGINE 3.3/3.8L9 - 151
INTAKE MANIFOLD - LOWER (Continued)

DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - EXCESSIVE EXHAUST SYSTEM NOISE
CONDITION POSSIBLE CAUSES CORRECTION
EXCESSIVE EXHAUST NOISE
(UNDER HOOD)1. Exhaust manifold cracked or
broken.1. Replace manifold.
2. Manifold to cylinder head leak. 2. Tighten manifold and/or replace
gasket.
3. EGR Valve to manifold gasket
leakage.3. Tighten fasteners or replace
gasket.
4. EGR Valve to EGR tube gasket
leakage.4. Tighten fasteners or replace
gasket.
5. EGR tube to manifold tube
leakage.5. Tighten tube nut.
6. Exhaust flex-joint to manifold
leak.6. Tighten joint fasteners and/or
replace gasket.
7. Exhaust flex-joint. 7. Replace catalytic converter
assembly.
8. Pipe and shell noise from front
exhaust pipe.8. Characteristic of single wall pipe.
EXCESSIVE EXHAUST NOISE 1. Leak at exhaust pipe joints. 1. Tighten clamps at leaking joints.
2. Burned or rusted out muffler
assembly or exhaust pipe.2. Replace muffler resonator tailpipe
assembly or exhaust pipe with
catalytic converter assembly.
3. Burned or rusted out resonator. 3. Replace muffler resonator tailpipe
assembly.
4. Restriction in exhaust system. 4. Perform Exhaust System
Restriction Check. Replace
component as necessary.
5. Converter material in muffler. 5. Replace muffler and converter
assemblies. Check fuel injection and
ignition systems for proper
operation.
DIAGNOSIS AND TESTING - EXHAUST SYSTEM
RESTRICTION CHECK
Exhaust system restriction can be checked by mea-
suring back pressure using the DRB IIItand PEP
module pressure tester.
WARNING: THE NORMAL OPERATING TEMPERA-
TURE OF THE EXHAUST SYSTEM IS VERY HIGH.
THEREFORE, NEVER WORK AROUND OR ATTEMPT
TO SERVICE ANY PART OF THE EXHAUST SYSTEM
UNTIL IT IS COOLED. SPECIAL CARE SHOULD BE
TAKEN WHEN WORKING NEAR THE CATALYTIC
CONVERTER. THE TEMPERATURE OF THE CON-
VERTER RISES TO A HIGH LEVEL AFTER A SHORT
PERIOD OF ENGINE OPERATION TIME.NOTE: For Special Tool identification, (Refer to 11 -
EXHAUST SYSTEM - SPECIAL TOOLS).
(1) Disconnect and remove the upstream (before
catalytic converter) oxygen sensor. (Refer to 14 -
FUEL SYSTEM/FUEL INJECTION/O2 SENSOR -
REMOVAL)
(2) Install the Exhaust Back Pressure Fitting
Adaptor CH8519.
(3) Connect the Low Pressure Sensor (15 psi)
CH7063 to the back pressure fitting.
(4) Following the PEP module instruction manual,
connect all required cables to the DRB IIItand PEP
module. Select the available menu options on the
DRBIIItdisplay screen for using the digital pressure
gauge function.
11 - 2 EXHAUST SYSTEMRS
EXHAUST SYSTEM (Continued)

SPECIAL TOOLS
EXHAUST SYSTEM
CATALYTIC CONVERTER
DESCRIPTION
The toe board three-way catalytic converter is con-
nected to the exhaust manifold by the use of flex
joint and a gasket. The outlet connects to the muffler
inlet pipe and is secured with a band type clamp
(Fig. 1).The exhaust flex-joint coupling (Fig. 3) is used to
secure the catalytic converter to the exhaust mani-
fold. The flex-joint has four bolts, four flag nuts and
a gasket that are separate parts from the exhaust
flex-joint. The flex-joint is welded to the catalytic
converter.
CAUTION: When servicing, care must be exercised
not to dent or bend the bellows or bellows cover of
the flex-joint. Should this occur, the flex-joint will
eventually fail and require the catalytic converter be
replaced.
OPERATION
The three-way catalytic converter simultaneously
converts three exhaust emissions into harmless
gases. Specifically, HC and CO emissions are con-
verted into water (H2O) and carbon dioxide (CO2).
Oxides of Nitrogen (NOx) are converted into Nitrogen
(N) and Oxygen. The three-way catalyst is most effi-
cient in converting HC, CO and NOx at the stoichio-
metric air fuel ratio of 14.7:1.
The oxygen content in a catalyst is important for
efficient conversion of exhaust gases. When a high
oxygen content (lean) air/fuel ratio is present for an
extended period, oxygen content in a catalyst can
reach a maximum. When a rich air/fuel ratio is
present for an extended period, the oxygen content in
the catalyst can become totally depleted. When this
occurs, the catalyst fails to convert the gases. This is
known as catalyst9punch through.9
Back Pressure Test Adapter - CH8519
Pressure Transducer CH7063
DRB III & PEP Module - OT-CH6010A
Fig. 3 Flex-joint
1 - FLANGE
2 - END CAPS
3 - CATALYTIC CONVERTER
4 - FLEXIBLE BELLOWS
11 - 4 EXHAUST SYSTEMRS
EXHAUST SYSTEM (Continued)

Catalyst operation is dependent on its ability to
store and release the oxygen needed to complete the
emissions-reducing chemical reactions. As a catalyst
deteriorates, its ability to store oxygen is reduced.
Since the catalyst's ability to store oxygen is some-
what related to proper operation, oxygen storage can
be used as an indicator of catalyst performance.
Refer to the appropriate Diagnostic Information for
diagnosis of a catalyst related Diagnostic Trouble
Code (DTC).
The combustion reaction caused by the catalyst
releases additional heat in the exhaust system, caus-
ing temperature increases in the area of the reactor
under severe operating conditions. Such conditions
can exist when the engine misfires or otherwise does
not operate at peak efficiency.Do notremove spark
plug wires from plugs or by any other means short
out cylinders. Failure of the catalytic converter can
occur due to temperature increases caused by
unburned fuel passing through the converter. This
deterioration of the catalyst core can result in exces-
sively high emission levels, noise complaints, and
exhaust restrictions.
Unleaded gasoline must be used to avoid ruining
the catalyst core. Do not allow engine to operate
above 1200 RPM in neutral for extended periods over
5 minutes. This condition may result in excessive
exhaust system/floor pan temperatures because of no
air movement under the vehicle.
The flex joint allows flexing as the engine moves,
preventing breakage that could occur from the back-
and-forth motion of a transverse mounted engine.
CAUTION: Due to exterior physical similarities of
some catalytic converters with pipe assemblies,
extreme care should be taken with replacement
parts. There are internal converter differences
required in some parts of the country (particularly
vehicles built for States with strict emission
requirements) and between model years.
REMOVAL
(1) Loosen clamp and disconnect the muffler/reso-
nator assembly from catalytic converter pipe.
(2) Disconnect downstream oxygen sensor electri-
cal connector (Fig. 4). For removal of downstream
oxygen sensor, (Refer to 14 - FUEL SYSTEM/FUEL
INJECTION/O2 SENSOR - REMOVAL).
(3) Remove catalytic converter to exhaust manifold
attaching fasteners (Fig. 5).
(4) Remove catalytic converter and gasket (Fig. 5).
Fig. 4 Downstream Oxygen Sensor
1 - OXYGEN SENSOR CONNECTOR
2 - CATALYTIC CONVERTER
3 - DOWNSTREAM OXYGEN SENSOR
4 - ENGINE HARNESS CONNECTOR
Fig. 5 Catalytic Converter to Exhaust Manifold
1 - FLAG NUT
2 - GASKET
3 - BOLT
4 - CATALYTIC CONVERTER
RSEXHAUST SYSTEM11-5
CATALYTIC CONVERTER (Continued)