spark plugs CHRYSLER CARAVAN 2003 Owner's Guide

SPECIFICATIONS - TORQUE
DESCRIPTION N´mFt.
Lbs.In.
Lbs.
Camshaft SprocketÐBolt 54 40 Ð
Camshaft Thrust
PlateÐBolts12 Ð 105
Connecting Rod
CapÐBolts54 +
1¤4
turn40
+1¤4
turnÐ
Crankshaft Main Bearing
CapÐBolts41 +
1¤4
turn30
+1¤4
turnÐ
Crankshaft Main Bearing
Cap Cross Bolts (3.8L)61 45 Ð
Crankshaft Oil Seal
Retainer RearÐBolts12 Ð 105
Crankshaft DamperÐBolt 54 40 Ð
Cylinder Block Drain
Plugs20 15 Ð
Cylinder HeadÐBolts (Refer to 9 - ENGINE/
CYLINDER HEAD -
INSTALLATION)
Cylinder Head CoverÐ
Bolts12 Ð 105
Flex Plate to Crankshaft 95 70 Ð
Engine Mounting (Refer to 9 - ENGINE/
ENGINE MOUNTING)
Exhaust ManifoldÐBolts 23 Ð 200
Exhaust Crossover
PipeÐBolts54 40 Ð
Intake Manifold -
LowerÐBolts23 Ð 200
Intake Manifold - Lower
Gasket RetainerÐBolts12 Ð 105
Intake Manifold
UpperÐBolts12 Ð 105
Lifter Yoke RetainerÐ
Bolts12 Ð 105
Oil Filter Attaching Fitting 54 40 Ð
Oil Cooler Attaching
Fitting27 20 Ð
Oil Filter 20 15 Ð
Oil Filter AdapterÐBolts 28 Ð 250
Oil Gallery Plug 27 20 Ð
Oil PanÐBolts 12 Ð 105
Oil Pan DrainÐPlug 27 20 Ð
Oil Pressure Switch 23 Ð 200
DESCRIPTION N´mFt.
Lbs.In.
Lbs.
Oil Pump Cover
PlateÐScrews12 Ð 105
Oil Pump Pick-up
TubeÐBolt28 Ð 250
Oil Dipstick HousingÐ
Bolts48 35 Ð
Rocker Arm ShaftÐBolts 23 Ð 200
Spark Plug 16 12 Ð
Timing Chain Case Cover
ÐM8 Bolt 27 20 Ð
ÐM10 Bolt 54 40 Ð
Water PumpÐBolts 12 Ð 105
Water Pump PulleyÐ
Bolts28 Ð 250
SPECIAL TOOLS
3.3/3.8L ENGINE
Dolly 6135
Cradle 6710A
RSENGINE 3.3/3.8L9-95
ENGINE 3.3/3.8L (Continued)
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CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also
be checked by using Bloc-Chek Kit C-3685-A or
equivalent. Perform test following the procedures
supplied with the tool kit.
REMOVAL - CYLINDER HEAD
(1) Drain the cooling system. (Refer to 7 - COOL-
ING - STANDARD PROCEDURE)
(2) Disconnect negative cable from battery.
(3) Remove upper and lower intake manifolds.
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - REMOVAL)
WARNING: INTAKE MANIFOLD GASKET IS MADE
OF VERY THIN METAL AND MAY CAUSE PER-
SONAL INJURY, HANDLE WITH CARE.
(4) Remove the cylinder head covers. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL)
(5) Remove the spark plugs from cylinder head.(6) Remove the dipstick and tube (Fig. 18).
(7) Remove exhaust manifold(s). (Refer to 9 -
ENGINE/MANIFOLDS/EXHAUST MANIFOLD -
REMOVAL)
(8) Remove rocker arm and shaft assemblies.(Refer
to 9 - ENGINE/CYLINDER HEAD/ROCKER ARMS -
REMOVAL) Remove push rods andmark positions
to ensure installation in original locations.
(9) Remove the eight head bolts from each cylinder
head and remove cylinder heads (Fig. 22).
CLEANING
To ensure engine gasket sealing, proper surface
preparation must be performed, especially with the
use of aluminum engine components and multi-layer
steel cylinder head gaskets.
NOTE: Multi-Layer Steel (MLS) head gaskets require
a scratch free sealing surface.
Remove all gasket material from cylinder head and
block (Refer to 9 - ENGINE - STANDARD PROCE-
Fig. 17 Cylinder Head and Components
1 - VALVE LOCKS 5 - SPRING SEATS
2 - RETAINERS 6 - CYLINDER HEAD
3 - VALVE SPRINGS 7 - VALVE - EXHAUST
4 - VALVE STEM SEALS 8 - VALVE - INTAKE
9 - 100 ENGINE 3.3/3.8LRS
CYLINDER HEAD (Continued)
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NOTE: Bolt torque after 1/4 turn should be over 122
N´m (90 ft. lbs.). If not, replace the bolt.
(6) Inspect push rods and replace worn or bent
rods.
(7) Install the push rods.
(8) Install the rocker arm and shaft assemblies.
(Refer to 9 - ENGINE/CYLINDER HEAD/ROCKER
ARMS - INSTALLATION)
(9) Install the cylinder head covers. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION)
(10) Install the exhaust manifolds. (Refer to 9 -
ENGINE/MANIFOLDS/EXHAUST MANIFOLD -
INSTALLATION)
(11) Install new O-ring on dipstick tube. Install
dipstick tube assembly (Fig. 18).
(12) Install the spark plugs.
(13) Install upper and lower intake manifolds.
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - INSTALLATION)
(14) Fill the cooling system. (Refer to 7 - COOL-
ING - STANDARD PROCEDURE)
(15) Connect negative cable to battery.
CYLINDER HEAD COVER(S)
DESCRIPTION
The cylinder head covers are made of stamped
steel. The covers are sealed with steel reinforced sil-
icon rubber gaskets. The cylinder head cover uses
rubber isolators at each fastener location (Fig. 23).
NOTE: Due to the tight packaging near the cylinder
head covers, which makes spill clean-up difficult, a
spill during an engine oil change may be misinter-
preted as an oil leak. When investigating an oil leak
in the location of the cylinder head covers and
intake manifold, follow the procedure found in Oil
Leak Diagnosis (Refer to 9 - ENGINE - DIAGNOSIS
AND TESTING) for determining the source of a leak.
CYLINDER HEAD COVER -
RIGHT
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove the wiper module. (Refer to 8 - ELEC-
TRICAL/WIPERS/WASHERS/WIPER MODULE -
REMOVAL)
(3) Disconnect spark plug wires from plugs.
(4) Disconnect PCV hose from cylinder head cover
(Fig. 24).
(5) Remove cylinder head cover bolts.
(6) Remove cylinder head cover and gasket (Fig.
23).
Fig. 21 Checking Bolts for Stretching (Necking)
1 - STRETCHED BOLT
2 - THREADS ARE NOT STRAIGHT ON LINE
3 - THREADS ARE STRAIGHT ON LINE
4 - UNSTRETCHED BOLT
Fig. 22 CYLINDER HEAD TIGHTENING SEQUENCE
Fig. 23 Cylinder Head Cover
1 - CYLINDER HEAD COVER
2 - BOLT
9 - 102 ENGINE 3.3/3.8LRS
CYLINDER HEAD (Continued)
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INSTALLATION
(1) Clean cylinder head and cover mating surfaces.
Inspect cylinder head cover surface for flatness.
Replace gasket as necessary.
(2) Inspect seal on the cover bolt for wear or dam-
age (Fig. 25). Replace bolt assembly as necessary.
NOTE: The cylinder head cover bolts contain a
torque limiter sleeve and a seal (Fig. 25). The seal
and torque sleeve is replaced with the bolt.
(3) Assemble gasket to cylinder cover by inserting
the bolt assemblies through each bolt hole on the
cover and gasket (Fig. 25).
(4) Install cylinder head cover and bolts (Fig. 26).
(5) Tighten cylinder head cover bolts to 12 N´m
(105 in. lbs.) (Fig. 26).
(6) Connect PCV hose to cylinder head cover.
(7) Connect spark plug wires to spark plugs.
(8) Install wiper module. (Refer to 8 - ELECTRI-
CAL/WIPERS/WASHERS/WIPER MODULE -
INSTALLATION)
(9) Connect negative cable to battery.
CYLINDER HEAD COVER -
LEFT
REMOVAL
(1) Disconnect spark plug wires from spark plugs.
(2) Disconnect crankcase vent hose from cylinder
head cover.
(3) Remove cylinder head cover bolts.
(4) Remove cylinder head cover and gasket.
INSTALLATION
(1) Clean cylinder head and cover mating surfaces.
Inspect cylinder head cover surface for flatness.
Replace gasket as necessary.
Fig. 24 PCV Hose
1 - HOSE - PCV
2 - P C V VA LV E
Fig. 25 CYLINDER HEAD COVER GASKET
1 - CYLINDER HEAD COVER
2 - BOLT
3 - SEAL (SERVICED WITH BOLT)
4 - GASKET
Fig. 26 Cylinder Head Cover
1 - CYLINDER HEAD COVER
2 - BOLT
RSENGINE 3.3/3.8L9 - 103
CYLINDER HEAD COVER - RIGHT (Continued)
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(2) Assemble gasket to cylinder cover by inserting
the fasteners through each bolt hole on cover and
gasket (Fig. 25).
(3) Install the cylinder head cover and bolts (Fig.
26).
(4) Tighten cylinder head cover bolts to 12 N´m
(105 in. lbs.) (Fig. 26).
(5) Connect crankcase vent hose.
(6) Connect spark plug wires to spark plugs.
INTAKE/EXHAUST VALVES &
SEATS
DESCRIPTION
The valves have chrome plated valve stems with
four-bead lock grooves. The valve stem seals are
made of Viton rubber.
OPERATION
The two valves per cylinder are opened using
hydraulic lifters, push rods, and rocker arms.
STANDARD PROCEDURE - REFACING VALVES
AND VALVE SEATS
The intake and exhaust valves and seats are
machined to specific angles (Fig. 27).
VALVES
(1) Inspect the remaining margin after the valves
are refaced (Fig. 28). (Refer to 9 - ENGINE - SPEC-
IFICATIONS)
VALVE SEATS
CAUTION: Remove metal from valve seat only. Do
not remove material from cylinder head (Fig. 29).
(1) When refacing valve seats, it is important that
the correct size valve guide pilot be used for reseat-ing stones. A true and complete surface must be
obtained.
(2) Measure the concentricity of valve seat using
dial indicator (Fig. 30). Total runout should not
exceed 0.051 mm (0.002 in.) total indicator reading.
(3) Inspect the valve seat using Prussian blue to
determine where the valve contacts the seat. To do
this, coat valve seatLIGHTLYwith Prussian blue
then set valve in place. Rotate the valve with light
pressure. If the blue is transferred to the center of
valve face, contact is satisfactory. If the blue is trans-
ferred to top edge of valve face, lower valve seat with
a 15 degree stone. If the blue is transferred to the
bottom edge of valve face raise valve seat with a 65
degrees stone.
NOTE: Valve seats which are worn or burned can
be reworked, provided that correct angle and seat
width are maintained. Otherwise cylinder head must
be replaced.
Fig. 27 Valve Face and Seat
1 - SEAT WIDTH
2 - FACE ANGLE
3 - SEAT ANGLE
4 - SEAT CONTACT AREA
Fig. 28 Valve Margin
1 - VALVE FACE
2 - VALVE MARGIN
Fig. 29 Refacing Valve Seats
1 - REFACING STONE MUST NOT CUT INTO CYLINDER HEAD
2-STONE
3 - PILOT
4 - SEAT
9 - 104 ENGINE 3.3/3.8LRS
CYLINDER HEAD COVER - LEFT (Continued)
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NOTE: Replace cylinder head if stem-to-guide clear-
ance exceeds specifications, or if guide is loose in
cylinder head.
INSTALLATION
(1) Coat valve stems with clean engine oil and
insert them in cylinder head.
(2) Install valve spring seat on head (Fig. 35).
(3) Install new seals on all valve stems and over
valve guides (Fig. 35). Install valve springs and valve
retainers (Fig. 35).
(4) Install the valve springs. (Refer to 9 -
ENGINE/CYLINDER HEAD/VALVE SPRINGS -
INSTALLATION)
VALVE SPRINGS
DESCRIPTION
The valve springs are a bee-hive shaped design
(Fig. 34). The springs are seated on a steel washer on
the cylinder head with retainers and locks retaining
the springs (Fig. 35). The springs are installed with
the smaller diameter against spring retainer (Fig.
34).
OPERATION
The valve spring returns the valve against its seat
for a positive seal of the combustion chamber.
REMOVAL
REMOVAL - CYLINDER HEAD OFF
(1) With the cylinder head on a bench, position
Special Tool C-3422-D with 8464 Adapter on the
valve and spring retainer (Fig. 36).
(2) Compress the spring only enough to remove the
valve retainer locks.
(3) Slowly release the spring tension and remove
the valve spring and retainer.
(4) For removal of the valve stem seal (Refer to 9 -
ENGINE/CYLINDER HEAD/VALVE STEM SEALS -
REMOVAL).
REMOVAL - CYLINDER HEAD ON
(1) Disconnect negative cable from battery.
(2) Remove spark plug wires and all spark plugs.
Fig. 32 Intake and Exhaust Valves
1 - MARGIN
2-FACE
3 - STEM
4 - VALVE SPRING RETAINER LOCK GROOVES
Fig. 33 Measuring Valve Guide Wear - Typical
Fig. 34 Valve Spring
1 - VALVE SPRING (TOP - SMALLER DIAMETER)
9 - 106 ENGINE 3.3/3.8LRS
INTAKE/EXHAUST VALVES & SEATS (Continued)
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(11) Repeat procedure for each cylinder requiring
valve spring removal.
INSPECTION
Whenever valves have been removed for inspection,
reconditioning or replacement, valve springs should
be tested (Fig. 38).As an example;the compression
length of a spring to be tested is 38.00 mm (1.496
in.). Turn the table of Tool C-647 until surface is in
line with the 38.00 mm (1.496 in.) mark on the
threaded stud and the zero mark on the front. Place
spring over stud on the table and lift compressing
lever to set tone device. Pull on torque wrench until
ping is heard. Take reading on torque wrench at this
instant. Multiply this reading by two. This will give
the spring load at test length. Fractional measure-
ments are indicated on the table for finer adjust-
ments. Refer to Engine Specifications to obtain
specified height and allowable tensions (Refer to 9 -
ENGINE - SPECIFICATIONS). Replace any springs
that do not meet specifications.
INSTALLATION
INSTALLATION - CYLINDER HEAD OFF
(1) If removed, install a new valve stem seal (Refer
to 9 - ENGINE/CYLINDER HEAD/VALVE STEM
SEALS - INSTALLATION).
(2) Position valve spring and retainer on spring
seat.(3) Using Special Tool C-3422-D with 8464 Adapter
(Fig. 36), compress the spring only enough to install
the valve retainer locks. Install valve retainer locks.
(4) Slowly release the spring tension. Ensure the
retainer locks are seated properly.
INSTALLATION - CYLINDER HEAD ON
(1) The intake valve stem seals should be pushed
firmly and squarely over the valve guide using the
valve stem as guide.Do Not Forceseal against top
of guide. When installing the valve retainer locks,
compress the springonly enoughto install the
locks.
CAUTION: Do not pinch seal between retainer and
top of valve guide.
(2) Follow the same procedure on the remaining 5
cylinders using the firing sequence 1-2-3-4-5-6.Make
sure piston in cylinder is at TDC on the valve
spring that is being covered.
(3) Remove spark plug adapter tool.
(4) Install rocker arms and shaft assembly. (Refer
to 9 - ENGINE/CYLINDER HEAD/ROCKER ARMS -
INSTALLATION)
(5) Install cylinder head covers. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION)
(6) Install spark plugs and connect wires.
(7) Connect negative cable to battery.
Fig. 37 VALVE SPRING - REMOVE/INSTALL (HEAD
ON)
1 - SPECIAL TOOL 8453
2 - BOLTS - SPECIAL TOOL ATTACHING
3 - AIR SUPPLY HOSE ADAPTER
Fig. 38 TESTING VALVE SPRING
1 - SPECIAL TOOL C-647
9 - 108 ENGINE 3.3/3.8LRS
VALVE SPRINGS (Continued)
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VALVE TIMING
STANDARD PROCEDURE
STANDARD PROCEDURE - VALVE TIMING
VERIFICATION
(1) Remove front cylinder head cover and all 6
spark plugs.
(2) Rotate engine until the #2 piston is at TDC of
the compression stroke.
(3) Install a degree wheel on the crankshaft pulley.
(4) With proper adaptor, install a dial indicator
into #2 spark plug hole. Using the indicator find TDC
on the compression stroke.
(5) Position the degree wheel to zero.
(6) Remove dial indicator from spark plug hole.
(7) Place a 5.08 mm (0.200 in.) spacer between the
valve stem tip of #2 intake valve and rocker arm pad.
Allow tappet to bleed down to give a solid tappet
effect.
(8) Install a dial indicator so plunger contacts the
#2 intake valve spring retainer as nearly perpendic-
ular as possible. Zero the indicator.
(9) Rotate the engine clockwise until the intake
valve has lifted .254 mm (0.010 in.).
CAUTION: Do not turn crankshaft any further clock-
wise as intake valve might bottom and result in
serious damage.
(10) Degree wheel should read 6 degrees BTDC to
6 degrees ATDC.
STANDARD PROCEDURE - MEASURING
TIMING CHAIN WEAR
NOTE: This procedure must be performed with the
timing chain cover removed (Refer to 9 - ENGINE/
VALVE TIMING/TIMING CHAIN COVER - REMOVAL).
(1) Position a scale next to timing chain so that
any movement of chain may be measured (Fig. 132).
(2) Position a torque wrench and socket on the
camshaft sprocket attaching bolt. Apply force in the
direction of crankshaft rotation to take up slack to
the following torque:
²41 N´m (30 ft. lb.) with cylinder heads installed
²20 N´m (15 ft. lb.) with cylinder heads removed
NOTE: With torque applied to the camshaft
sprocket bolt, crankshaft should not be permitted to
move. It may be necessary to block crankshaft to
prevent rotation.
(3) Holding a measuring scale along edge of chain
links (Fig. 132).(4) Apply force in the reverse direction to the fol-
lowing torque:
²41 N´m (30 ft. lb.) with cylinder heads installed
²20 N´m (15 ft. lb.) with cylinder heads removed
(5) Measure amount of sprocket/chain movement.
(6) Install a new timing chain and sprockets if
movement exceeds 3.175 mm (1/8 in.).
TIMING CHAIN COVER
REMOVAL
(1) Disconnect negative cable from battery.
(2) Drain cooling system. (Refer to 7 - COOLING -
STANDARD PROCEDURE)
(3) Raise vehicle on hoist.
(4) Drain engine oil.
(5) Remove right wheel and inner splash shield.
(6) Remove oil pan. (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PAN - REMOVAL)
(7) Remove oil pick-up tube (Fig. 133).
(8) Remove accessory drive belt. (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL)
(9) Remove A/C compressor and set aside.
(10) Remove crankshaft vibration damper. (Refer
to 9 - ENGINE/ENGINE BLOCK/VIBRATION
DAMPER - REMOVAL)
(11) Remove radiator lower hose.
(12) Remove heater hose from timing chain cover
housing (Fig. 134) or water pump inlet tube (if
engine oil cooler equipped) (Fig. 135).
(13) Remove the right side engine mount. (Refer to
9 - ENGINE/ENGINE MOUNTING/RIGHT MOUNT
- REMOVAL)
(14) Remove idler pulley from engine bracket (Fig.
136).
(15) Remove the engine mount bracket (Fig. 136).
Fig. 132 Measuring Timing Chain Wear
1 - TORQUE WRENCH
RSENGINE 3.3/3.8L9 - 153
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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, if exhaust system is equipped with a
catalytic converter. 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).
INSPECTION
WARNING: THE NORMAL OPERATING TEMPERA-
TURE OF THE EXHAUST SYSTEM IS VERY HIGH.
THEREFORE, NEVER ATTEMPT TO SERVICE ANY
PART OF THE EXHAUST SYSTEM UNTIL IT IS
COOLED. SPECIAL CARE SHOULD BE TAKEN
WHEN WORKING NEAR THE CATALYTIC CON-
VERTER. THE TEMPERATURE OF THE CONVERTER
RISES TO A HIGH LEVEL AFTER A SHORT PERIOD
OF ENGINE OPERATION TIME.Check catalytic converter for a flow restriction.
(Refer to 11 - EXHAUST SYSTEM - DIAGNOSIS
AND TESTING) Exhaust System Restriction Check
for procedure.
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)
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period the switch ratio reaches a predetermined
value, a counter is incremented by one. The monitor
is enabled to run another test during that trip. When
the test fails 6 times, the counter increments to 3, a
malfunction is entered, and a Freeze Frame is stored,
the code is matured and the MIL is illuminated. If
the first test passes, no further testing is conducted
during that trip.
The MIL is extinguished after three consecutive
good trips. The good trip criteria for the catalyst
monitor is more stringent than the failure criteria. In
order to pass the test and increment one good trip,
the downstream sensor switch rate must be less than
45% of the upstream rate. The failure percentages
are 59% respectively.
Enabling ConditionsÐThe following conditions
must typically be met before the PCM runs the cat-
alyst monitor. Specific times for each parameter may
be different from engine to engine.
²Accumulated drive time
²Enable time
²Ambient air temperature
²Barometric pressure
²Catalyst warm-up counter
²Engine coolant temperature
²Vehicle speed
²MAP
²RPM
²Engine in closed loop
²Fuel level
Pending ConditionsÐ
²Misfire DTC
²Front Oxygen Sensor Response
²Front Oxygen Sensor Heater Monitor
²Front Oxygen Sensor Electrical
²Rear Oxygen Sensor Rationality (middle check)
²Rear Oxygen Sensor Heater Monitor
²Rear Oxygen Sensor Electrical
²Fuel System Monitor
²All TPS faults
²All MAP faults
²All ECT sensor faults
²Purge flow solenoid functionality
²Purge flow solenoid electrical
²All PCM self test faults
²All CMP and CKP sensor faults
²All injector and ignition electrical faults
²Idle Air Control (IAC) motor functionality
²Vehicle Speed Sensor
²Brake switch (auto trans only)
²Intake air temperature
ConflictÐThe catalyst monitor does not run if any
of the following are conditions are present:
²EGR Monitor in progress (if equipped)
²Fuel system rich intrusive test in progress
²EVAP Monitor in progress²Time since start is less than 60 seconds
²Low fuel level-less than 15 %
²Low ambient air temperature
²Ethanol content learn is taking place and the
ethanol used once flag is set
SuspendÐThe Task Manager does not mature a
catalyst fault if any of the following are present:
²Oxygen Sensor Monitor, Priority 1
²Oxygen Sensor Heater, Priority 1
²EGR Monitor, Priority 1 (if equipped)
²EVAP Monitor, Priority 1
²Fuel System Monitor, Priority 2
²Misfire Monitor, Priority 2
OPERATION - NON-MONITORED CIRCUITS
The PCM does not monitor all circuits, systems
and conditions that could have malfunctions causing
driveability problems. However, problems with these
systems may cause the PCM to store diagnostic trou-
ble codes for other systems or components. For exam-
ple, a fuel pressure problem will not register a fault
directly, but could cause a rich/lean condition or mis-
fire. This could cause the PCM to store an oxygen
sensor or misfire diagnostic trouble code.
The major non-monitored circuits are listed below
along with examples of failures modes that do not
directly cause the PCM to set a DTC, but for a sys-
tem that is monitored.
FUEL PRESSURE
The fuel pressure regulator controls fuel system
pressure. The PCM cannot detect a clogged fuel
pump inlet filter, clogged in-line fuel filter, or a
pinched fuel supply or return line. However, these
could result in a rich or lean condition causing the
PCM to store an oxygen sensor, fuel system, or mis-
fire diagnostic trouble code.
SECONDARY IGNITION CIRCUIT
The PCM cannot detect an inoperative ignition coil,
fouled or worn spark plugs, ignition cross firing, or
open spark plug cables. The misfire will however,
increase the oxygen content in the exhaust, deceiving
the PCM in to thinking the fuel system is too lean.
Also see misfire detection.
CYLINDER COMPRESSION
The PCM cannot detect uneven, low, or high engine
cylinder compression. Low compression lowers O2
content in the exhaust. Leading to fuel system, oxy-
gen sensor, or misfire detection fault.
EXHAUST SYSTEM
The PCM cannot detect a plugged, restricted or
leaking exhaust system. It may set a EGR (if
equipped) or Fuel system or O2S fault.
RSEMISSIONS CONTROL25-5
EMISSIONS CONTROL (Continued)
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