ignition CHRYSLER VOYAGER 1996 Service Manual

MODULE CONTROL TRANSMISSION
(CONTINUED ON NEXT PAGE)
BLACK
+ + + + + + + + +
2011 101
6051 50
40 21
41
T20 18LB T19 18WT T16 18RD T16 18RD
T15 18LG T14 18LG/WT
T13 18DB/BK K22 18OR/DB F11 18RD/WT
T10 18YL/DG T9 18OR/BK F45 18YL/RD
D21 18PK K24 18GY/BK D2 18WT/BK T3 18VT T1 18LG/BK
40 39
38 37 36
35 34 33
32 31 30
29 28 27
26 25 24
23 22 21
20 19 18
17 16 15
14 13 12
11 10 9
8 7 6
5 4 3
2 1 CAV LOW/REVERSE SOLENOID CONTROL
2-4 SOLENOID CONTROL TRANSMISSION CONTROL RELAY OUTPUT TRANSMISSION CONTROL RELAY OUTPUT
12 VOLT SUPPLY OUTPUT SHAFT SPEED SENSOR SIGNAL
SPEED SENSOR GROUND THROTTLE POSITION SENSOR SIGNAL FUSED IGNITION (ST-RUN-OFF)
TORQUE MANAGEMENT REQUEST SENSE OVERDRIVE PRESSURE SWITCH SENSE FUSED IGNITION (ST)
SCI TRANSMIT CRANKSHAFT POSITION SENSOR SIGNAL CCD BUS(-) TRANSMISSION RANGE SWITCH T3 SENSE TRANSMISSION RANGE SWITCH T1 SENSE
- -
- - -
- - -
- - -
- - -
- - -
- - - - - - CIRCUIT
- -
- - -
- - -
- - -
- - -
- - -
- - - - - - FUNCTION
NS/GS8W-80 CONNECTOR PIN-OUTS 8W - 80 - 85
NSGS8085J988W-3

(CONTINUED)
T60 18BR T59 18PK G7 18WT/OR
Z13 16BK/RD A5 18RD/DB T54 18VT/LG Z14 16BK/YL T52 18RD/BK
K4 18BK/LB T50 18DG T47 18YL/BK D6 18PK/LB D1 18VT/BR T42 18VT/WT T41 18BK/WT
60 59
58 57 56
55 54 53
52 51 50
49 48 47
46 45 44
43 42 41 CAV OVERDRIVE SOLENOID CONTROL
UNDERDRIVE SOLENOID CONTROL
VEHICLE SPEED SENSOR SIGNAL
EATX GROUND FUSED B(+) EATX GROUND INPUT SPEED SENSOR SIGNAL
SENSOR GROUND LOW/REVERSE PRESSURE SWITCH SENSE 2/4 PRESSURE SWITCH SENSE SCI RECEIVE CCD BUS(+) TRANSMISSION RANGE SWITCH T42 SENSE TRANSMISSION RANGE SWITCH T41 SENSE
- - - - - CIRCUIT
- - - - - FUNCTION
RANGE SENSORTRANSMISSION
5
10
61BLACK
T41 18BR/YL T42 18VT/WT
T3 18VT T1 18LG/BK L1 18VT/BK
T41 18BK/WT T54 18VT/LG T13 18DB/BK F20 18WT
109 8
7
6 5 4
3 2 1 CAV TRANSMISSION RANGE SENSOR T41 SENSE
TRANSMISSION RANGE SENSOR T42 SENSE TRANSMISSION RANGE SENSOR T3 SENSE TRANSMISSION RANGE SENSOR T1 SENSE
BACK-UP LAMP FEED TRANSMISSION RANGE SENSOR T41 SENSE TRANSMISSION TEMPERATURE SENSOR SIGNAL
SPEED SENSOR GROUND FUSED IGNITION SWITCH OUTPUT
- CIRCUIT
- FUNCTION 5 634 8 721 BLACK
T19 18WT T20 18LB T60 18BR
T59 18PK T16 18RD T9 18OR/BK
T50 18DG T47 18YL/BK
8 7
6 5 4
3 2 1 CAV 2/4 SOLENOID CONTROL LOW/REVERSE SOLENOID CONTROL OVERDRIVE SOLENOID CONTROL
UNDERDRIVE PRESSURE SWITCH SENSE TRANSMISSION CONTROL RELAY OUTPUT OVERDRIVE PRESSURE SWITCH SENSE
LOW/REVERSE PRESSURE SWITCH SENSE 2/4 PRESSURE SWITCH SENSE CIRCUIT
FUNCTION
TRANSMISSION
CONTROL SOLENOIDS
TRANSMISSION TEMPERATURE SENSOR SIGNAL
8W - 80 - 86 8W-80 CONNECTOR PIN-OUTSNS/GS
J988W-3NSGS8086

(EXCEPT BUILT-UP-EXPORT)MODULEWIPER- - - - - - - -
BLACK
GROUND WIPER HIGH/LOW RELAY HIGH SPEED OUTPUT
WIPER PARK SWITCH SENSE WIPER HIGH/LOW RELAY LOW SPEED OUTPUT105
6 1Z1 14BK V4 12RD/YL
V7 20DG/WT V3 12BR/WT
109
8 7 6
5 4 3
2 1 CAV
- - CIRCUIT - - FUNCTION
1
14
GROUND Z1 14BK(BUILT-UP-EXPORT)MODULEWIPER
CAV CIRCUIT FUNCTION
1 V3 12BR/WT WIPER HIGH/LOW RELAY LOW SPEED OUTPUT
2 V7 20DG/WT WIPER PARK SWITCH SENSE
3 V4 12RD/YL WIPER HIGH/LOW RELAY HIGH SPEED OUTPUT
4
(EXCEPT 3.3L/3.8L)SENSOR VEHICLE SPEED3 28 VOLT SUPPLY K7 18OR
G7 18WT/OR VEHICLE SPEED SENSOR SIGNAL K4 20BK/LB* SENSOR GROUNDFUSED IGNITION (ST-RUN)
CAV CIRCUIT FUNCTION
1
F87 18WT/BK* 1
K4 18BK/LB SENSOR GROUND
2
* DIESEL BLACK
BLACK
1 3
8W - 80 - 88 8W-80 CONNECTOR PIN-OUTSNS/GS
J988W-3NSGS8088

Component/
GroundColor Location Fig.
G100 LT Frame Rail 3
G101 2.4L Rear of
Cylinder Head6, 7
G101 3.3L, 3.8L Rear of
Cylinder Block9
G102 LT Frame Rail 3
G103 2.4L Rear of
Cylinder Head6, 7
G103 3.3L, 3.8L Rear of
Cylinder Block9
G104 Rear of Right
Headlamp4
G200 Right of I.P.
Center Stack10
G201 I.P. Center
Support10
G202 I.P. Center
Support10
G204 I.P. Center
Support10
G300 LT Kick Panel 13
G301 RT Kick Panel 14
G302 LT Quarter
Panel21
G400 In Liftgate 23
Generator BK Rear of
Generator5, 6, 7,
8, 9
Glove Box
LampBL Rear of Glove
Box11
Glow #1 BK At Glow Plug 8
Glow #2 BK At Glow Plug 8
Glow #3 BK At Glow Plug 8
Glow #4 BK At Glow Plug 8
Headlamp
Dimmer SwitchBK Part of
Multifunction
Switch11
Headlamp
Switch C1NAT Rear of Switch 11
Headlamp
Switch C2BK Rear of Switch 11
Headlamp
Washer PumpBK At Pump N/S
High Note Horn BK LT Frame Rail 4
Hood Ajar
SwitchNAT LT Fender 2Component/
GroundColor Location Fig.
Horn Switch Rear of Driver
Airbag11
Idle Air Control
MotorBK On Throttle
Body5, 6, 7,
8, 9
Ignition Coil
Pack 2.0LBK Top of Valve
Cover5
Ignition Coil
Pack 2.4LBK Top of Valve
Cover6, 7
Ignition Coil
Pack 3.3L, 3.8LBK RT Side of
Engine9
Ignition Switch
C1GY Rear of Switch 11
Ignition Switch
C2GN Rear of Switch 11
Ignition Switch
C3BK Rear of Switch 11
Instrument
ClusterRD Rear of Cluster 11
Intake Air Temp
SensorGY On Intake 6, 7
J01D BK RT Side of
HVAC15
J02A BK Top of Liftgate 23
JO3A BK Top of Liftgate 23
Junction Block
C1GY On Junction
Block13
Junction Block
C2GY On Junction
Block13
Junction Block
C3GY On Junction
Block12
Junction Block
C4GY On Junction
Block12
Key-In Halo
LampWT Rear of Lamp 11
Knock Sensor
2.0LGY Front of
Cylinder Block5
Knock Sensor
2.4LGY Front of
Cylinder Block6, 7
Knock Sensor
3.3L, 3.8LGY Front of
Cylinder BlockN/S
L15 BK Top of Liftgate 23
L16 BK Top of Liftgate 23
Left Flasher
RelayBK LT Rear
Quarter PanelN/S
Left Door Ajar
SwitchBK LT B-PIllar 14
NS/GS8W - 90 CONNECTOR/GROUND LOCATIONS 8W - 90 - 3
DESCRIPTION AND OPERATION (Continued)

Component/
GroundColor Location Fig.
Headlamp
Switch C1NAT Rear of Switch 11
Headlamp
Switch C2BK Rear of Switch 11
Headlamp
Washer MotorBottom of
ReserviorN/S
High Note Horn BK LT Frame Rail 4
Hood Ajar
SwitchNAT LT Fender 2
Horn Switch Rear of Driver
Airbag11
Idle Air Control
MotorBK On Throttle
Body5, 6, 7,
8, 9
Ignition Coil
Pack 2.4LBK Top of Valve
Cover6, 7
Ignition Coil
Pack 3.3L, 3.8LBK RT Side of
Engine9
Ignition Switch
C1GY Rear of Switch 11
Ignition Switch
C2GN Rear of Switch 11
Ignition Switch
C3BK Rear of Switch 11
Instrument
ClusterRD Rear of Cluster 11
Intake Air Temp
SensorGY On Intake 6, 7
J01D BK RT Side of
HVAC15
J02A BK Top of Liftgate 23
JO3A BK Top of Liftgate 23
Junction Block
C1GY On Junction
Block12, 13
Junction Block
C2GY On Junction
Block12, 13
Junction Block
C3GY On Junction
Block12
Junction Block
C4GY On Junction
Block12
Key-In Halo
LampWT Rear of Lamp 11
Knock Sensor
2.4LGY Front of
Cylinder Block6, 7
Knock Sensor
3.3L, 3.8LGY Front of
Cylinder BlockN/S
L15 BK Top of Liftgate 23Component/
GroundColor Location Fig.
L16 BK Top of Liftgate 23
Left
Combination
RelayBK LT Rear
Quarter PanelN/S
Left Door Ajar
SwitchBK LT B-PIllar 12
Left Door
Arm/Disarm
SwitchBK At Switch 19
Left Door
Courtesy LampBK At Lamp 19
Left Door
SpeakerBK At Speaker 19
Left Fog Lamp GY At Lamp 4
Left Front Door
Lock MotorBK At Motor 19
Left Front Panel
SpeakerBK At Speaker 11
Left Front
Park/Turn
Signal LampBK At Lamp 4
Left Front
Wheel Speed
SensorBK LT Fender Side
Shield2
Left Front
Window MotorRD At Motor 19
Left Headlamp BK At Lamp 2
Left Headlamp
Leveling MotorBK At Motor N/S
Left Liftgate
Flood LampBK At Lamp 23
Left Mid
Reading LampGY At Lamp 17
Left Power Door
Lock SwitchBK At Switch 19
Left Power
Mirror C1RD At Mirror 11
Left Power
Mirror C2BL At Mirror 11
Left Power
Window SwitchOR At Switch 19
Left Rear Lamp
AssemblyBK At Lamp 21
Left Rear Door
Ajar SwitchBK LT C-Pillar 21
Left Rear Pillar
SpeakerBK At Speaker 21
NS/GS8W - 90 CONNECTOR/GROUND LOCATIONS 8W - 90 - 33
DESCRIPTION AND OPERATION (Continued)

made to seal the area between the bedplate and cyl-
inder block without disturbing the bearing clearance
or alignment of these components.
GASKET DISASSEMBLY
Parts assembled with form-in-place gaskets may be
disassembled without unusual effort. In some
instances, it may be necessary to lightly tap the part
with a mallet or other suitable tool to break the seal
between the mating surfaces. A flat gasket scraper
may also be lightly tapped into the joint but care
must be taken not to damage the mating surfaces.
SURFACE PREPARATION
Scrape clean or wire brush all gasket surfaces to
remove all loose material. Inspect stamped parts to
ensure gasket rails are flat. Gasket surfaces must be
free of oil and dirt. Make sure old gasket material is
removed from blind attaching holes.
FORM-IN-PLACE GASKET APPLICATION
Assembling parts using a form-in-place gasket
requires care but it's easier then using precut gas-
kets.
MopartGasket Maker material should be applied
sparingly 1 mm (0.040 in.) diameter or less of sealant
to one gasket surface. Be certain the material sur-
rounds each mounting hole. Excess material can eas-
ily be wiped off. Components should be torqued in
place within 15 minutes. The use of a locating dowel
is recommended during assembly to prevent smear-
ing the material off location.
TheMopartSilicone Rubber Adhesive Sealant
gasket material or equivalent should be applied in a
continuous bead approximately 3 mm (0.120 in.) in
diameter. All mounting holes must be circled. For
corner sealing, a 3.17 or 6.35 mm (1/8 or 1/4 in.) drop
is placed in the center of the gasket contact area.
Uncured sealant may be removed with a shop towels.
Components should be torqued in place while the
sealant is still wet to the touch (within 10 minutes).
The usage of a locating dowel is recommended during
assembly to prevent smearing of material off loca-
tion.
CRANKSHAFT SPROCKET BOLT ACCESS PLUG
An Access plug is located in the right inner fender
shield. Remove the plug and insert the proper size
socket, extension and ratchet, when crankshaft rota-
tion is necessary.
ENGINE CORE PLUGS
REMOVAL
Using a blunt tool such as a drift or a screwdriver
and a hammer, strike the bottom edge of the cup
plug (Fig. 1). With the cup plug rotated, grasp firmlywith pliers or other suitable tool and remove plug
(Fig. 1).
CAUTION: Do not drive cup plug into the casting
as restricted cooling can result and cause serious
engine problems.
INSTALLATION
Thoroughly remove all rust and clean inside of cup
plug hole in cylinder block or head. Be sure to
remove old sealer. Lightly coat inside of cup plug hole
with sealer. Make certain the new plug is cleaned of
all oil or grease. Using proper drive plug, drive plug
into hole so that the sharp edge of the plug is at
least 0.5 mm (0.020 inch.) inside the lead in chamfer
(Fig. 1).
It is in not necessary to wait for curing of the seal-
ant. The cooling system can be refilled and the vehi-
cle placed in service immediately.
ENGINE PERFORMANCE
If a loss of performance is noticed, timing belt or
chain may have skipped one or two teeth. Camshaft
and crankshaft timing should be checked. Refer to
Group 9, Engine Timing belt or chain installation.
It is important that the vehicle is operating to its
optimum performance level to maintain fuel economy
and lowest vehicle emissions. If vehicle is not operat-
ing to these standards, refer to Engine Diagnosis out-
lined is this section. The following procedures can
assist in achieving the proper engine diagnosis.
(1) Test cranking amperage draw. Refer to Group
8B, Starting.
(2) Check intake manifold for vacuum leaks.
(3) Perform cylinder compression pressure test.
Refer to Engine Diagnosis, outlined in this section.
(4) Clean or replace spark plugs as necessary and
adjust gap as specified in Group 8D, Ignition System.
Tighten to specifications.
Fig. 1 Core Hole Plug Removal
9 - 2 ENGINENS
GENERAL INFORMATION (Continued)

(5) Test resistance of spark plug cables. Refer to
Group 8D, Ignition System.
(6) Test ignition coils primary and secondary resis-
tance. Replace parts as necessary. Refer to Group 8D,
Ignition System.
(7) Check fuel pump pressure at idle and different
RPM ranges. Refer to Group 14, Fuel System for
Specifications.
(8) The air filter elements should be replaced as
specified in Group 0, Lubrication and Maintenance.
(9) Inspect crankcase ventilation system as out-
lined in Group 25, Emission Control Systems.
(10) Road test vehicle as a final test.
HONING CYLINDER BORES
(1) Used carefully, the cylinder bore resizing hone
C-823 equipped with 220 grit stones, is the best tool
for this job. In addition to deglazing, it will reduce
taper and out-of-round as well as removing light
scuffing, scoring or scratches. Usually a few strokes
will clean up a bore and maintain the required lim-
its.
(2) Deglazing of the cylinder walls may be done
using a cylinder surfacing hone, Tool C-3501,
equipped with 280 grit stones, if the cylinder bore is
straight and round. 20-60 strokes depending on the
bore condition, will be sufficient to provide a satisfac-
tory surface. Inspect cylinder walls after each 20
strokes, using a light honing oil.Do not use engine
or transmission oil, mineral spirits or kerosene.
(3) Honing should be done by moving the hone up
and down fast enough to get a cross-hatch pattern.
When hone marksintersectat 50-60 degrees, the
cross hatch angle is most satisfactory for proper seat-
ing of rings (Fig. 2).(4) A controlled hone motor speed between
200-300 RPM is necessary to obtain the proper cross-
hatch angle. The number of up and down strokes per
minute can be regulated to get the desired 50-60
degree angle. Faster up and down strokes increase
the cross-hatch angle.
(5) After honing, it is necessary that the block be
cleaned again to remove all traces of abrasive.
CAUTION: Ensure all abrasives are removed from
engine parts after honing. It is recommended that a
solution of soap and hot water be used with a
brush and the parts then thoroughly dried. The bore
can be considered clean when it can be wiped
clean with a white cloth and cloth remains clean.
Oil the bores after cleaning to prevent rusting.
MEASURING MAIN BEARING AND CONNECTING
ROD BEARING CLEARANCES
PLASTIGAGE METHOD
Engine crankshaft bearing clearances can be deter-
mined by use of Plastigage or equivalent. The follow-
ing is the recommended procedure for the use of
Plastigage:
NOTE: The total clearance of the main bearings
can only be determined by removing the weight of
the crankshaft. This can be accomplished by either
of two methods:
PREFERRED METHOD
Shimming the bearings adjacent to the bearing to
be checked in order to remove the clearance between
upper bearing shell and the crankshaft. This can be
accomplished by placing a minimum of 0.254 mm
(0.010 in.) shim (e. g. cardboard, matchbook cover,
etc.) between the bearing shell and the bearing cap
on the adjacent bearings and tightening bolts to
14-20 N´m (10-15 ft. lbs.). The number of main bear-
ing will vary from engine to engine.
Fig. 2 Cylinder Bore Cross-Hatch Pattern
Fig. 3 Plastigage Placed in Lower Shell
NSENGINE 9 - 3
GENERAL INFORMATION (Continued)

ENGINE DIAGNOSIS
INDEX
page page
DIAGNOSIS AND TESTING
CYLINDER COMBUSTION
PRESSURE LEAKAGE TEST.............. 8
CYLINDER COMPRESSION PRESSURE TEST . . 7
ENGINE DIAGNOSISÐMECHANICAL......... 12
ENGINE DIAGNOSISÐPERFORMANCE...... 10GENERAL INFORMATION.................. 7
INSPECTION
(ENGINE OIL LEAKS IN GENERAL)......... 8
INTAKE MANIFOLD LEAKAGE DIAGNOSIS..... 7
LASH ADJUSTER (TAPPET)
NOISE DIAGNOSIS...................... 8
DIAGNOSIS AND TESTING
GENERAL INFORMATION
Engine diagnosis is helpful in determining the
causes of malfunctions.
These malfunctions may be classified as either
mechanical (e.g., a strange noise), or performance
(e.g., engine idles rough and stalls).
Refer to the Service DiagnosisÐMechanical Chart
and the Service DiagnosisÐPerformance Chart, for
possible causes and corrections of malfunctions. Refer
to Group 14, Fuel System, for the fuel system diag-
nosis.
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
²Engine Cylinder Head Gasket Failure Diagnosis
²Intake Manifold Leakage Diagnosis
INTAKE MANIFOLD LEAKAGE DIAGNOSIS
An intake manifold air leak is characterized by
lower than normal manifold vacuum. Also, one or
more cylinders may not be functioning.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR THE FAN.
DO NOT WEAR LOOSE CLOTHING.
(1) Start the engine.
(2) Spray a small stream of water (Spray Bottle) at
the suspected leak area.
(3) If a change in RPM'S, the area of the suspected
leak has been found.
(4) Repair as required.
CYLINDER COMPRESSION PRESSURE TEST
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) Check engine oil level and add oil if necessary.
(2) Drive the vehicle until engine reaches normal
operating temperature. Select a route free from traf-
fic and other forms of congestion, observe all traffic
laws, and accelerate through the gears several times
briskly.
(3) Remove all spark plugs from engine. As spark
plugs are being removed, check electrodes for abnor-
mal firing indicators fouled, hot, oily, etc. Record cyl-
inder number of spark plug for future reference.
(4) Disconnect coil wire from distributor and
secure to good ground to prevent a spark from start-
ing a fire (Conventional Ignition System). For Direct
Ignition System DIS disconnect the coil connector.
(5) Be sure throttle blade is fully open during the
compression check.
(6) Insert compression gage adaptor into the #1
spark plug hole in cylinder head. Crank engine until
maximum pressure is reached on gage. Record this
pressure as #1 cylinder pressure.
(7) Repeat the previous step for all remaining cyl-
inders.
(8) Compression should not be less than (689kPa)
100 psi and not vary more than 25 percent from cyl-
inder to cylinder.
(9) If one or more cylinders have abnormally low
compression pressures, repeat the compression test.
(10) If the same cylinder or cylinders repeat an
abnormally low reading on the second compression
test, it could indicate the existence of a problem in
the cylinder in question.The recommended com-
pression pressures are to be used only as a
guide to diagnosing engine problems. An engine
should not be disassembled to determine the
NSENGINE 9 - 7

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 DIAGNOSISÐPERFORMANCE
CONDITION POSSIBLE CAUSE CORRECTION
ENGINE WILL NOT START 1. Weak battery. 1. Test battery. Charge or replace
as necessary.Refer to Group 8A,
Battery.
2. Corroded or loose battery
connections.2. Clean and tighten battery
connections. Apply a coat of light
mineral grease to terminals.
3. Faulty starter. Test starting system. Refer to Group
8B, Starting.
4. Moisture on ignition wires. 4. Remove moisture from wires.
5. Faulty ignition cables. 5. Replace any cracked or shorted
cables.
6. Faulty coil or control unit. 6. Test and replace as needed.
Refer to Group 8D, Ignition System
7. Incorrect spark plug gap. 7. Set gap. Refer to Group 8D,
Ignition System.
8. Contamination in fuel system. 8. Clean system and replace fuel
filter.
9. Faulty fuel pump. 9. Test fuel pump and replace as
needed. Refer to Group 14, Fuel
System.
ENGINE STALLS OR IDLES
ROUGH1. Idle speed too low. 1. Test minimum air flow. Refer to
Group 14, Fuel System.
2. Incorrect fuel mixture. 2. Refer to Group 14, Fuel System.
3. Intake manifold leakage. 3. Inspect intake manifold, manifold
gasket, and vacuum hoses. Refer to
Group 11, Exhaust System and
Intake Manifold.
4. Incorrect ignition wiring. 4. Install correct wiring.
5. Faulty coil(s) 5. Test and replace as necessary.
Refer to Group 8D, Ignition System.
ENGINE LOSS OF POWER 1. Dirty or incorrectly gapped plugs. 1. Clean plugs and set gap. Refer to
Group 8D, Ignition System.
2. Contamination in fuel system. 2. Clean system and replace fuel
filter.
3. Faulty fuel pump. 3. Test and replace as necessary.
Refer to Group 14, Fuel System.
4. Incorrect valve timing. 4. Correct valve timing.
5. Leaking cylinder head gasket. 5. Replace cylinder head gasket.
6. Low compression. 6. Test compression of each
cylinder.
7. Burned, warped, or pitted valves. 7. Replace valves.
8. Plugged or restricted exhaust
system.8. Install new parts, as necessary.
9. Faulty ignition cables. 9. Replace any cracked or shorted
cables.
10. Faulty coil(s). 10. Test and replace as necessary.
Refer to Group 8D, Ignition System.
9 - 10 ENGINENS
DIAGNOSIS AND TESTING (Continued)