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.
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. 2).
(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. 6).
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-
DURE). Be careful not to gouge or scratch the alumi-
num head sealing surface.
Clean all engine oil passages.
INSPECTION
(1) Before cleaning, check for leaks, damage and
cracks.
(2) Clean cylinder head and oil passages.
(3) Check cylinder head for flatness (Fig. 3).
(4) Cylinder head must be flat within:
Fig. 2 DIPSTICK & TUBE
1 - DIPSTICK
2 - BOLT
3 - TUBE
RSENGINE 3.3/3.8L SUPPLEMENT9s-17
CYLINDER HEAD (Continued)
(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. 2).
(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. 7).
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. 8).
(5) Remove cylinder head cover bolts.
(6) Remove cylinder head cover and gasket (Fig.
7).
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. 9). Replace bolt assembly as necessary.
NOTE: The cylinder head cover bolts contain a
torque limiter sleeve and a seal (Fig. 9). The seal
and torque sleeve is replaced with the bolt.
Fig. 7 Cylinder Head Cover
1 - CYLINDER HEAD COVER
2 - BOLT
Fig. 8 PCV Hose
1 - HOSE - PCV
2 - P C V VA LV E
RSENGINE 3.3/3.8L SUPPLEMENT9s-19
CYLINDER HEAD (Continued)
(3) Assemble gasket to cylinder cover by inserting
the bolt assemblies through each bolt hole on the
cover and gasket (Fig. 9).
(4) Install cylinder head cover and bolts (Fig. 10).
(5) Tighten cylinder head cover bolts to 12 N´m
(105 in. lbs.) (Fig. 10).
(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.
(2) Assemble gasket to cylinder cover by inserting
the fasteners through each bolt hole on cover and
gasket (Fig. 9).
(3) Install the cylinder head cover and bolts (Fig.
10).
(4) Tighten cylinder head cover bolts to 12 N´m
(105 in. lbs.) (Fig. 10).
(5) Connect crankcase vent hose.
(6) Connect spark plug wires to spark plugs.
Fig. 9 CYLINDER HEAD COVER GASKET
1 - CYLINDER HEAD COVER
2 - BOLT
3 - SEAL (SERVICED WITH BOLT)
4 - GASKET
Fig. 10 Cylinder Head Cover
1 - CYLINDER HEAD COVER
2 - BOLT
9s - 20 ENGINE 3.3/3.8L SUPPLEMENTRS
CYLINDER HEAD COVER-RIGHT (Continued)
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. 20).
(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.
(3) Remove cylinder head cover(s). (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL)
(4) Remove rocker arms and shaft. (Refer to 9 -
ENGINE/CYLINDER HEAD/ROCKER ARMS -
REMOVAL)
(5) Rotate engine until the piston in the cylinder
bore requiring spring removal is at TDC.
(6) Install Special Tool 8453 to the cylinder head
(Fig. 21). Tighten the attaching bolts to 23 N´m (200
in. lbs.).
Fig. 19 VALVE 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
9s - 24 ENGINE 3.3/3.8L SUPPLEMENTRS
VALVE SPRINGS (Continued)
(7) Install a spark plug adapter in the spark plug
hole. Connect air hose that can supply 620.5±689 kPa
(90±100 psi) of air pressure to adapter. This is to
hold valves in place while servicing components.
(8) Locate the forcing screw and spring retainer
adapter assembly over the spring requiring removal
(Fig. 21).
(9) Slowly turn the forcing screw clockwise (com-
pressing the valve spring) until the valve keepers can
be removed.
(10) Turn forcing screw counterclockwise to relieve
spring tension. Remove retainer and valve spring.
(11) Repeat procedure for each cylinder requiring
valve spring removal.
INSPECTION
NOTE: The are two different types of valve springs
used that are interchangable, but have different
specifications(Refer to 9 - ENGINE/CYLINDER
HEAD/VALVE SPRINGS - DESCRIPTION).
Whenever valves have been removed for inspection,
reconditioning or replacement, valve springs should
be tested (Fig. 22).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. Placespring 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.
Fig. 20 VALVE SPRING - REMOVE/INSTALL
1 - SPECIAL TOOL C-3422-D SPRING COMPRESSOR
2 - SPECIAL TOOL 8464 ADAPTER
Fig. 21 VALVE SPRING - REMOVE/INSTALL (HEAD
ON)
1 - SPECIAL TOOL 8453
2 - BOLTS - SPECIAL TOOL ATTACHING
3 - AIR SUPPLY HOSE ADAPTER
Fig. 22 TESTING VALVE SPRING
1 - SPECIAL TOOL C-647
RSENGINE 3.3/3.8L SUPPLEMENT9s-25
VALVE SPRINGS (Continued)
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. 20), 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 (Fig. 23).
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
(Fig. 23).
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.
ROCKER ARMS
DESCRIPTION
DESCRIPTION - ROCKER ARMS
The rocker arms are installed on the rocker arm
shaft. The rocker arms and shaft assembly is
attached to the cylinder head with seven billeted
bolts and retainers. The rocker arms are made of
stamped steel.
DESCRIPTION - PUSHRODS
The pushrods are made of steel and are a hollow
design. The pushrods are positioned between the
hydraulic lifter and the rocker arm.
OPERATION
OPERATION - ROCKER ARMS
The rocker arm pivots on the rocker shaft. Rocker
arms are used to translate up and down motions pro-
vided by the camshaft, hydraulic lifter, and pushrod
on one end, into a down and up motions on the valve
stem on the opposing end.
OPERATION - PUSHRODS
The pushrod is a solid link between the hydraulic
lifter and the rocker arm. Also, the pushrod supplies
engine oil from the hydraulic lifter to the rocker arm.
Fig. 23 VALVE SPRING INSTALLED
1 - VALVE SPRING RETAINER
2 - VALVE INSTALLED HEIGHT
3 - CYLINDER HEAD SURFACE
4 - VALVE SPRING SEAT SURFACE
5 - VALVE SPRING INSTALLED HEIGHT
9s - 26 ENGINE 3.3/3.8L SUPPLEMENTRS
VALVE SPRINGS (Continued)
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)
the O-RINGS ONLY (Fig. 18)to aid assembly. Use
care when removing hoses to prevent damage to hose
or hose nipple.
(1) Carefully place idle air control motor into
throttle body.
(2) Install mounting screw. Tighten screw to 7 N´m
(62 in. lbs.) torque.
(3) Connect electrical connector to idle air control
motor.
(4) Connect negative cable to battery.
INLET AIR TEMPERATURE
SENSOR
DESCRIPTION
The IAT Sensor is a Negative Temperature Coeffi-
cient (NTC) Sensor that provides information to the
PCM regarding the temperature of the air entering
the intake manifold (Fig. 19).
MAP SENSOR
DESCRIPTION
The MAP sensor (Fig. 20) or (Fig. 21) mounts to
the intake manifold. The sensor is connects electri-
cally to the PCM.
OPERATION
The MAP serves as a PCM input, using a silicon
based sensing unit, to provide data on the manifold
vacuum that draws the air/fuel mixture into the com-
bustion chamber. The PCM requires this information
to determine injector pulse width and spark advance.
When MAP equals Barometric pressure, the pulse
width will be at maximum.
Also like the cam and crank sensors, a 5 volt ref-
erence is supplied from the PCM and returns a volt-age signal to the PCM that reflects manifold
pressure. The zero pressure reading is 0.5V and full
scale is 4.5V. For a pressure swing of0Ð15psithe
voltage changes 4.0V. The sensor is supplied a regu-
lated 4.8 to 5.1 volts to operate the sensor. Like the
cam and crank sensors ground is provided through
the sensor return circuit.
The MAP sensor input is the number one contrib-
utor to pulse width. The most important function of
the MAP sensor is to determine barometric pressure.
The PCM needs to know if the vehicle is at sea level
or is it in Denver at 5000 feet above sea level,
because the air density changes with altitude. It will
also help to correct for varying weather conditions. If
a hurricane was coming through the pressure would
be very, very low or there could be a real fair
Fig. 18 O-RINGS
1 - O-rings
Fig. 19 3.3/3.8L IAT SENSOR
Fig. 20 MAP SENSOR - 2.4L
14 - 30 FUEL INJECTIONRS
IDLE AIR CONTROL MOTOR (Continued)