cause of low compression unless some malfunc-
tion is present.
(11) Clean or replace spark plugs as necessary
and adjust gap as specified in Group 8, Electrical.
Tighten to specifications.
(12) Test resistance of spark plug cables. Refer to
Group 8, Electrical Ignition System Secondary Cir-
cuit Inspection.
(13) Test coil output voltage, primary and second-
ary resistance. Replace parts as necessary. Refer to
Group 8, Electrical Ignition System.
(14) Check fuel pump pressure at idle and differ-
ent RPM ranges. Refer to Group 14, Fuel System for
Specifications.
(15) The air filter elements should be replaced as
specified in Group 0, Lubrication and Maintenance,.
(16) Inspect crankcase ventilation system as out
lined in Group 0, Lubrication and Maintenance. For
emission controls see Group 25, Emission Controls
for service procedures.
(17) Inspect and adjust accessory belt drives refer-
ring to Group 7, Cooling System, Accessory Drive
Belts for proper adjustments.
(18) Road test vehicle as a final test.
CYLINDER COMBUSTION PRESSURE LEAKAGE
TEST
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
jacket.
²Any causes for combustion/compression pressure
loss.
WARNING: DO NOT REMOVE THE RADIATOR CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM 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 the engine
OFF.
Clean spark plug recesses with compressed air.
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 procedures on each cylinder
according to the tester manufacturer's instructions.
While testing, listen for pressurized air escaping
through the throttle body, tailpipe and 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.
LASH ADJUSTER (TAPPET) NOISE DIAGNOSIS
A tappet-like noise may be produced from several
items. Check the following items.
(1) Engine oil level too high or too low. This may
cause aerated oil to enter the adjusters and cause
them to be spongy.
(2) Insufficient running time after rebuilding cylin-
der head. Low speed running up to 1 hour may be
required.
(3) During this time, turn engine off and let set for
a few minutes before restarting. Repeat this several
times after engine has reached normal operating
temperature.
(4) Low oil pressure.
(5) The oil restrictor pressed into the vertical oil
passage to the cylinder head is plugged with debris.
(6) Air ingested into oil due to broken or cracked
oil pump pick up.
(7) Worn valve guides.
(8) Rocker arm ears contacting valve spring
retainer.
(9) Rocker arm loose, adjuster stuck or at maxi-
mum extension and still leaves lash in the system.
(10) Faulty lash adjuster.
a. Check lash adjusters for sponginess while
installed in cylinder head. Depress part of rocker
arm over adjuster. Normal adjusters should feel very
firm. Spongy adjusters can be bottomed out easily.
b. Remove suspected lash adjusters, and disassem-
bleDo not reuse retainer caps. Do not inter-
change parts and make sure that care and
cleanliness is exercised in the handling of parts.
c. Clean out dirt and varnish with solvent.
d. Reassemble with engine oil.
e. Check for sponginess.
f. If still spongy, replace with new adjuster.
INSPECTION (ENGINE OIL LEAKS IN GENERAL)
Begin with a through visual inspection of the
engine, particularly at the area of the suspected leak.
If an oil leak source is not readily identifiable, the
following steps should be followed:
(1) Do not clean or degrease the engine at this
time because some solvents may cause rubber to
swell, temporarily stopping the leak.
9 - 8 ENGINENS
DIAGNOSIS AND TESTING (Continued)
ENGINE ASSEMBLY
REMOVAL
(1) Disconnect the battery.
(2) Remove the air cleaner assembly and inlet
hose.
(3) Remove both hoses at intercooler and engine.
(4) Disconnect EGR vacuum hose.
(5) Disconnect brake booster vacuum hose.
(6) Disconnect oil pressure switch connector (Fig.
19).
(7) Disconnect Wiring harness bracket at transaxle
shift tower.
(8) Disconnect transaxle wiring at speed sensor,
crank sensor, and backup light switch.
(9) Remove both transmission shift cables at trans-
mission.
(10) Remove negative battery cable at cylinder
block (Fig. 19).
(11) Remove oil separator.
(12) Remove connectors at coolant temperature
sensor and A/C compressor.
(13) Disconnect fuel injection pump wiring connec-
tors (Fig. 19).
(14) Disconnect glow plug connectors.
(15) Disconnect electrical connector at number 1
fuel injector.
(16) Raise vehicle on hoist.
(17) Remove right side splash shield (Fig. 20).
WARNING: THE COOLANT IN A RECENTLY OPER-
ATED ENGINE IS HOT AND PRESSURIZED. USE
CARE TO PREVENT SCALDING BY HOT COOLANT.CAREFULLY RELEASE THE PRESSURE BEFORE
REMOVING THE RADIATOR DRAIN COCK AND CAP.
(18) Drain the cooling system (refer to Group 7,
Cooling).
(19) Lower vehicle.
(20) Remove Coolant pressure bottle and discon-
nect low coolant level sensor.
(21) Disconnect both heater hoses.
(22) Remove the lower radiator hose.
(23) Remove the upper radiator hose.
(24) Remove fuel line at injector pump and cap.
(25) Remove power steering reservoir and reposi-
tion.
(26) Remove upper radiator crossmember.
(27) Disconnect cooling fan module connector.
Fig. 18 Shift Cables at Rear MountFig. 19 Component Locations
Fig. 20 Right Side Splash Shield
NS/GSENGINE 9 - 53
REMOVAL AND INSTALLATION (Continued)
70É using angle torque tool. Then rotate the bolts an
additional 70É following tightening sequence.
(10) Then, tighten the 14mm bolts with special
tool VM-1018 in the following manner:
(11) Side bolts (M1-M2): Tighten M1 bolts to 30
N´m, then rotate them 85É (65). Tighten M2 bolts to
30 N´m, then rotate them 85É (65).
(12)2nd Phase:After 20 minutes of engine oper-
ation at operating temperature, allow engine to cool
down completely. Then retorque the head bolts as fol-
lows:
(13) Central bolts A-L: Starting from bolt A,
slacken and retorque it immediately to 30 N´m + 65É.
Rotate the bolt an additional 65É. Then proceed in
the same way, bolt by bolt, following alphabetical
order, as indicated.
(14) Side bolts M1-M2:Without slackening,
torque bolts M1 then bolts M2 to 90 N´m (66 ft. lbs.).
(15) Tighten intake nuts to 30 N´m (22 ft. lbs.) and
exhaust manifolds nuts to 30 N´m (22 ft. lbs.) speci-
fied torque after completing Phase 2.
(16) If the engine cylinder head is to be replaced
and the original valves used, measure the valve stem
diameter. Only standard size valves can be used with
a service replacement engine cylinder head unless
the replacement head valve stem guide bores are
reamed to accommodate oversize valve stems.
Remove all carbon buildup and reface the valves.
(17) Tighten oil feed lines for rocker arm assem-
blies and oil pressure switch to 13 N´m (112 in. lbs.).
(18) Install push rods and rocker arm assemblies,
tighten nut to 29.4 N´m (264 in. lbs.).(19) Install fuel injectors use tool VM-1012 (refer
to Group 14, Fuel System).
(20) Install valve cover, tighten nuts to 14.7 N´m
(132 in. lbs.).
(21) Connect crankcase breather hose.
(22) Connect the injector sensor wire connector,
and the glow plug connectors.
(23) Install oil feed line, tighten banjo bolts to 12.7
N´m (108 in. lbs), and oil drain line to turbo.
(24) Install water manifold tighten bolts to 12 N´m
(106 in. lbs.).
(25) Install exhaust pipe to turbo elbow, tighten
bolts to 28 N´m (250 in. lbs.).
(26) Install the support strut from block to turbo-
charger exhaust elbow.
(27) Install EGR tube to EGR valve, tighten bolts
to 26 N´m (19 ft. lbs.).
(28) Install intercooler hoses at intake manifold.
(29) Install coolant pressure bottle and hoses.
(30) Install wiper module. Refer to Group 8K,
Windshield Wiper Unit Installation for procedure.
(31) Install intercooler hose at turbocharger tube.
(32) Install fuel injector lines from the pump to
injectors, tighten nuts to 17.6 N´m (156. lbs.).
(33) Connect the upper radiator hose.
(34) Connect negative cable to battery.
(35) Fill the cooling system. Check for leaks.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN DIRECT
LINE WITH THE FAN. DO NOT PUT HANDS NEAR
THE PULLEYS, BELTS OR FAN. DO NOT WEAR
LOOSE CLOTHING.
Fig. 33 Engine Cylinder Head Bolt Tightening Sequence
NS/GSENGINE 9 - 59
REMOVAL AND INSTALLATION (Continued)
(5) Drain cooling system. Refer to Group 7, Cool-
ing System for procedure.
(6) Remove heater, and upper radiator hoses at
intake manifold.
(7) Disconnect coolant temperature sensor (Fig.
14).
(8) Remove the accessory drive belt. Refer to
Accessory Drive belt Removal and Installation in
Group 7, Cooling System for procedure.
(9) Remove fasteners attaching generator bracket
to cylinder head, and block.
(10) Remove intake manifold center support
bracket bolts (Y bracket) (Fig. 15)
(11) Disconnect fuel injector harness.(12) Remove lower intake manifold fasteners (Fig.
16). Remove the manifold from engine.
(13) Inspect and clean manifold. Refer to Cleaning
and Inspection outlined in this section for proce-
dures.
INSTALLATION
If the following items were removed, install and
torque to:
²Fuel Rail Bolts 22 N´m (200 in. lbs.)
²Engine Outlet Connector Bolts 28 N´m (250 in.
lbs.)
²Coolant Temperature Sensor 7 N´m (60 in. lbs.)
²Intake Air Temperature Sensor 28 N´m (250 in.
lbs.)
(1) Using a new intake gasket, position intake
manifold on the engine and install retaining bolts.
Fig. 13 Fuel Line Quick Disconnect
Fig. 14 Coolant Temperature SensorÐ2.4L
Fig. 15 Intake Manifold Center Support Bracket
Fig. 16 Intake Manifold Fasteners
NSEXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 7
REMOVAL AND INSTALLATION (Continued)
(12) Remove fasteners from Air Intake Plenum to
Intake Manifold (Fig. 22).(13) Remove Air Intake Plenum (Fig. 23).
(14) Cover intake manifold with suitable cover
when servicing (Fig. 24).
(15) Disconnect Fuel Injector wiring harness from
engine wiring harness.
Fig. 19 Electrical and Vacuum Connections to
Throttle Body
Fig. 20 Ignition Coil Removal
Fig. 21 Coolant Temperature Sensor Electrical
Connections
Fig. 22 Air Intake Plenum to Intake Manifold
Attaching Bolts
Fig. 23 Removing Air Intake Plenum
Fig. 24 Vacuum Connections for Fuel Rail and Fuel
Pressure Regulator
NSEXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 9
REMOVAL AND INSTALLATION (Continued)
(10) Connect fuel line to fuel rail (Fig. 21). Torque
hose clamps to 1 N´m (10 in. lbs.).
(11) Connect vacuum harness to air intake ple-
num.
(12) Connect and coolant temperature sensor elec-
trical connector to sensor (Fig. 21).
(13) Connect PCV and brake booster supply hose
to intake plenum.
(14) Connect automatic idle speed (AIS) motor
and throttle position sensor (TPS) electrical connec-
tors (Fig. 19).
(15) Connect vacuum vapor harness to throttle
body (Fig. 19).
(16) Install throttle cable and transaxle kickdown
linkage (Fig. 18).
(17) Install air inlet resonator hose assembly to
throttle body.
(18) Install radiator to thermostat housing hose
and heater hose to heater pipe nipple.
(19) Fill cooling system. Refer to Filling the Cool-
ing System outlined in Group 7 Cooling System for
procedure.
(20) Connect negative battery cable.
(21) With the DRB Scan Tool use ASD Fuel Sys-
tem Test to pressurize system to check for leaks.
CAUTION: When using the ASD Fuel System Test,
The Auto Shutdown (ASD) Relay will remain ener-
gized for 7 minutes or until the ignition switch is
turned to the OFF position, or Stop All Test is
selected.
EXHAUST MANIFOLDÐ3.0L ENGINE
REMOVAL
(1) Raise vehicle and disconnect exhaust pipe
from rear (cowl side) exhaust manifold at the flex-
joint.(2) Disconnect Oxygen Sensor lead wire at the
rear exhaust manifold (Fig. 28).
(3) Remove bolts attaching cross-over pipe to
manifold (Fig. 30).
(4) Remove rear heat shield (Fig. 29).
(5) Remove nuts attaching rear manifold to cylin-
der head and remove manifold.
(6) Lower vehicle and remove screws attaching
front heat shield to front manifold (Fig. 31).
(7) Remove bolts fastening crossover pipe to front
exhaust manifold and nuts fastening manifold to cyl-
inder head. Remove assemblies.
(8) Inspect and clean manifolds. Refer to Cleaning
and Inspection outlined in this section for proce-
dures.
INSTALLATION
Install the gaskets with the numbers 1-3-5
embossed on the top on the rear bank and those with
numbers 2-4-6 on the front (Radiator side) bank (Fig.
32).
(1) Install rear exhaust manifold and tighten
attaching nuts to 20 N´m (175 in. lbs.).
Fig. 27 Intake Plenum Tightening Sequence
Fig. 28 Disconnect Up Stream Heated Oxygen
Sensor Connection
Fig. 29 Rear Exhaust Manifold Heat Shield
NSEXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 11
REMOVAL AND INSTALLATION (Continued)
(25) Remove intake manifold bolts. Remove intake
manifold.
(26) Inspect and clean manifold. Refer to Cleaning
and Inspection outlined in this section for proce-
dures.
WARNING: INTAKE MANIFOLD GASKET IS MADE
OF VERY THIN METAL AND MAY CAUSE PER-
SONAL INJURY, HANDLE WITH CARE.
(27) Remove intake manifold seal retainers screws
(Fig. 43). Remove intake manifold gasket.
INSTALLATION
(1) Clean all surfaces of cylinder block and cylin-
der heads.
(2) Place a drop (approximately 1/4 in. diameter)
of MopartSilicone Rubber Adhesive Sealant or
equivalent, onto each of thefourmanifold to cylinder
head gasket corners (Fig. 44).(3) Carefully install the new intake manifold gas-
ket (Fig. 43). Torque end seal retainer screws to 12
N´m (105 in. lbs.).
(4) Install intake manifold and 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. 42). Then torque
again to 22 N´m (200 in. lbs.). After intake manifold
is in place,inspect to make sure seals are in
place.
Fig. 38 Intake Manifold Plenum Bolts and Nuts
Fig. 39 Fuel Rail Attaching Bolts
Fig. 40 Coolant Temperature Sensor Electrical
Connector
Fig. 41 Fuel Rail Removal
11 - 14 EXHAUST SYSTEM AND INTAKE MANIFOLDNS
REMOVAL AND INSTALLATION (Continued)
(5) Make sure the injector holes are clean and all
plugs have been removed.
(6) Lube injector O-ring with a drop of clean
engine oil to ease installation.(7) Put the tip of each injector into their ports.
Push the assembly into place until the injectors are
seated in the ports (Fig. 41).
(8) Install the fuel rail attaching bolts and torque
to 22 N´m (200 in. lbs.) (Fig. 39).
(9) Install fuel tube retaining bracket screw and
torque to 4 N´m (35 in. lbs.) (Fig. 39).
(10) Connect cam sensor and coolant temperature
sensor (Fig. 40).
(11) Remove covering on lower intake manifold
and clean surface.
(12) Place the new intake manifold gasket on
lower manifold. Put upper manifold into place and
install bolts and nuts finger tight.
NOTE: At no time should the studs be replaced
with a bolt and washer.
(13) Install the generator bracket to intake mani-
fold bolt and the cylinder head to intake manifold
strut bolts. (Do not torque.)
(14) Torque intake manifold bolts to 28 N´m (250
in. lbs.) following torque sequence in (Fig. 38).
(15) Torque generator bracket to intake manifold
bolt to 54 N´m (40 ft. lbs.).
(16) Torque the cylinder head to intake manifold
strut bolts to 54 N´m (40 ft. lbs.) (Fig. 35).
(17) Connect ground strap and MAP sensor electri-
cal connectors.
(18) Connect vacuum harness to intake plenum
(Fig. 34).
(19) Using a new gasket, connect the EGR tube
flange to the intake manifold and torque to 22 N´m
(200 in. lbs.).
(20) Clip wiring harness into the hole in the throt-
tle cable bracket.
(21) Connect the wiring connectors to the throttle
position sensor (TPS) and Automatic Idle Speed (AIS)
motor (Fig. 33).
(22) Connect vacuum harness to throttle body (Fig.
33).
(23) Install the direct ignition system (DIS) coils.
Torque fasteners to 12 N´m (105 in. lbs.) (Fig. 37).
(24) Lubricate the end of the chassis fuel tube
with 30 wt. oil. Connect fuel supply hose to chassis
fuel tube assembly. Pull back on the quick connect
fitting to ensure complete insertion (Fig. 36). (Refer
to Fuel Hoses, Clamps and Quick Connect Fittings in
Group 14 Fuel Systems).
(25) Install throttle cable. Refer to Group 14 Fuel
System for procedure.
(26) Connect fuel injector wiring harness.
(27) Install air cleaner and hose assembly.
(28) Connect negative battery cable. Fill Cooling
System. See Cooling System, Group 7.
(29) With the DRB Scan Tool use ASD Fuel Sys-
tem Test to pressurize system to check for leaks.
Fig. 42 Intake Manifold Removal and Installation
Fig. 43 Intake Manifold Gasket
Fig. 44 Intake Manifold Gasket Sealing
NSEXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 15
REMOVAL AND INSTALLATION (Continued)