spark DODGE NEON 2000 Service User Guide

CRANKSHAFT POSITION SENSOR
The crankshaft position sensor mounts to the
engine block behind the generator, just above the oil
filter (Fig. 15).
REMOVAL
(1) Disconnect electrical connector from crankshaft
position sensor.
(2) Remove sensor mounting screw. Remove sensor.
INSTALLATION
(1) Install sensor. Install sensor mounting screw
and tighten.
(2) Connect electrical connector to crankshaft posi-
tion sensor.
KNOCK SENSOR
The knock sensor threads into the side of the cyl-
inder block in front of the starter (Fig. 16).
REMOVAL
(1) Disconnect electrical connector from knock sen-
sor.
(2) Use a crow foot socket to remove the knock
sensors.
INSTALLATION
(1) Install knock sensor. Tighten knock sensor to
10 N´m (7 ft. lbs.) torque.Over or under tighten-
ing effects knock sensor performance, possibly
causing improper spark control.
(2) Attach electrical connector to knock sensor.
IGNITION SWITCH
The ignition switch attaches to the lock cylinder
housing on the end opposite the lock cylinder (Fig.
17). For ignition switch terminal and circuit identifi-
cation, refer to the Wiring Diagrams sections.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Place key cylinder in RUN position. Through
the hole in the lower shroud, depress lock cylinder
retaining tab and remove key cylinder (Fig. 18).
(3) Remove upper and lower shrouds from steering
column.
Fig. 15 Crankshaft Position Sensor
1 ± CRANKSHAFT POSITION SENSOR
2 ± GENERATOR
3 ± OIL FILTER
Fig. 16 Knock Sensor
Fig. 17 Ignition SwitchÐViewed From Below
Column
1 ± IGNITION SWITCH
2 ± LOCK CYLINDER HOUSING
3 ± RETAINING TABS
8D - 8 IGNITION SYSTEMPL
REMOVAL AND INSTALLATION (Continued)

TORQUE SPECIFICATION
DESCRIPTION TORQUE
Camshaft Position Sensor Screw.......... 9N´m
(80 in. lbs.)
SOHC Cam Magnet/Target . . . 3.4 N´m (30 in. lbs.)
Crankshaft Position Sensor Screw........ 9N´m
(80 in. lbs.)
Coolant Temp. Sensor.....18.6 N´m (165 in. lbs.)
Ignition Coil to Cyl. Head . . 11.9 N´m (105 in. lbs.)
Knock Sensor.............. 10N´m(90in.lbs.)
MAP/IAT Sensor Plastic Manifold......... 2N´m
(20 in. lbs.)
Spark Plugs................ 28N´m(20ft.lbs.)
SPARK PLUG CABLE RESISTANCEÐSOHC
SPARK PLUG
Engine Spark Plug Gap Thread Size
2.0L RC9YC 0.033 TO 0.038 14mm (3/4 in.) reach
IGNITION COIL
Coil ManufacturePrimary Resistance at 21ÉC-27ÉC
(70ÉF-80ÉF)Secondary Resistance at 21ÉC-27ÉC
(70ÉF-80ÉF)
Weastec (Steel Towers) 0.45 to 0.65 Ohms 11,500 to 13,500 Ohms
Diamond (copper towers) 0.53 to 0.65 Ohms 10,900 to 14,700 Ohms
CABLE RESISTANCE
#1,#4 3500 ohmsÐ 4900 ohms
#2,#3 2950 ohmsÐ 4100 ohms
Coil Polarity
Coil Polarity
PLIGNITION SYSTEM 8D - 11
SPECIFICATIONS (Continued)

AUDIO SYSTEM
TABLE OF CONTENTS
page page
GENERAL INFORMATION
INTRODUCTION..........................1
DESCRIPTION AND OPERATION
INTERFERENCE ELIMINATION...............1
DIAGNOSIS AND TESTING
AUDIO DIAGNOSTIC TEST PROCEDURES......1
TESTING................................1
BENCH TEST FOR ANTENNA MALFUNCTION...7REMOVAL AND INSTALLATION
CD CHANGER............................7
FRONT DOOR SPEAKER....................8
INSTRUMENT PANEL SPEAKER(S)...........8
MAST and ANTENNA ASSEMBLY.............8
RADIO..................................9
REAR SHELF SPEAKER(S).................10
GENERAL INFORMATION
INTRODUCTION
Operating instructions for the factory installed
audio systems can be found in the Owner's Manual
provided with the vehicle.
The vehicles are equipped with an Interior (Igni-
tion Off Draw) fuse in the Power Distribution Center
located in the engine compartment. After the Interior
(IOD) fuse or battery has been disconnected the clock
will require resetting. The radio station presets have
a nonvolatile memory and will retain the preset sta-
tions after a battery disconnect.
The available radio options are:
²AM/FM Stereo Cassette w/Clock
²AM/FM/CD
²AM/FM Cassette w/CD Changer Controls and
Display
²CD/4 Disc Changer - In-Dash (used w/Radio CD
Changer Controls)
DESCRIPTION AND OPERATION
INTERFERENCE ELIMINATION
The radio utilizes a ground wire plugged on to a
blade terminal and is bolted to the radio chassis.
Both connector and terminal should be securely
attached. The engine has two separate ground straps
to suppress ignition noise which may interfere with
radio reception.
²Left engine mount clip on strap
²Engine to shock tower reinforcement
Inductive type spark plug cables in the high ten-
sion circuit of the ignition system complete the inter-
ference suppression. Faulty or deteriorated spark
plug wires should be replaced.
DIAGNOSIS AND TESTING
AUDIO DIAGNOSTIC TEST PROCEDURES
CAUTION: The CD player will only operate between
approximate temperatures of -23ÉC and +65ÉC (-10ÉF
and +145ÉF).
Whenever a radio malfunction occurs;
(1) First check FUSES:
(a) Power Distribution Center (PDC), Interior
lamp fuse, M1 - Radio Memory Feed
(b) Fuse Block:
(I) Fuse 12, Illumination in the fuse block
(II) Fuse 16, Ignition feed in the fuse block
NOTE: The vehicles are shipped with the INTERIOR
LAMP fuse disconnected.
(2) Verify, the radio wire harness are properly con-
nected before starting normal diagnosis and repair
procedures. Refer to Audio Diagnostic Charts and/or
Group 8W, Wiring Diagrams, Radio Section.
TESTING
The antenna has a short cable which connects into
the instrument panel harness. The connection is
made on the right side of the instrument panel.
Antenna performance may be tested by substitut-
ing a known good antenna. It is also possible to
check short or open circuits with an ohmmeter or
continuity light once the antenna cable is discon-
nected from the radio as follows:
(1) Continuity should be present between the
antenna mast and radio end pin of antenna cable
plug (Fig. 1).
(2) No continuity should be observed or a very
high resistance of several megohms between the
ground shell of the connector and radio end pin.
PLAUDIO SYSTEM 8F - 1

WARNING: DO NOT ALLOW FLAME OR SPARKS
NEAR THE BATTERY. GASES ARE ALWAYS
PRESENT IN AND AROUND THE BATTERY.
WARNING: ALWAYS REMOVE RINGS, WATCHES,
LOOSE HANGING JEWELRY, AND LOOSE CLOTH-
ING.
TAKE OUTS
The abbreviation T/O is used in the component
location section to indicate a point in which the wir-
ing harness branches out to a component.
ELECTROSTATIC DISCHARGE (ESD) SENSITIVE
DEVICES
All ESD sensitive components are solid state and a
symbol (Fig. 2) is used to indicate this. When han-
dling any component with this symbol comply with
the following procedures to reduce the possibility of
electrostatic charge build up on the body and inad-
vertent discharge into the component. If it is not
known whether the part is ESD sensitive, assume
that it is.
(1) Always touch a known good ground before han-
dling the part. This should be repeated while han-
dling the part and more frequently after sliding
across a seat, sitting down from a standing position,
or walking a distance.
(2) Avoid touching electrical terminals of the part,
unless instructed to do so by a written procedure.
(3) When using a voltmeter, be sure to connect the
ground lead first.
(4) Do not remove the part from its protective
packing until it is time to install the part.
(5) Before removing the part from its package,
ground the package to a known good ground on the
vehicle.
DIAGNOSIS AND TESTING
TROUBLESHOOTING TOOLS
When diagnosing a problem in an electrical circuit
there are several common tools necessary. These tools
are listed and explained below.²Jumper Wire - This is a test wire used to con-
nect two points of a circuit. It can be used to bypass
an open in a circuit.
WARNING: NEVER USE A JUMPER WIRE ACROSS
A LOAD, SUCH AS A MOTOR, CONNECTED
BETWEEN A BATTERY FEED AND GROUND.
²Voltmeter - Used to check for voltage on a cir-
cuit. Always connect the black lead to a known good
ground and the red lead to the positive side of the
circuit.
CAUTION: Most of the electrical components used
in today's vehicle are solid state. When checking
voltages in these circuits use a meter with a 10-me-
gohm or greater impedance rating.
²Ohmmeter - Used to check the resistance
between two points of a circuit. Low or no resistance
in a circuit means good continuity.
CAUTION: - Most of the electrical components used
in today's vehicle are Solid State. When checking
resistance in these circuits use a meter with a
10-megohm or greater impedance rating. In addi-
tion, make sure the power is disconnected from the
circuit. Circuits that are powered up by the vehicle
electrical system can cause damage to the equip-
ment and provide false readings.
²Probing Tools - These tools are used for probing
terminals in connectors (Fig. 3). Select the proper
size tool from Special Tool Package 6807, and insert
it into the terminal being tested. Use the other end
of the tool to insert the meter probe.
INTERMITTENT AND POOR CONNECTIONS
Most intermittent electrical problems are caused
by faulty electrical connections or wiring. It is also
possible for a sticking component or relay to cause a
problem. Before condemning a component or wiring
assembly check the following items.
Fig. 2 Electrostatic Discharge Symbol
Fig. 3 Probing Tool
1 ± SPECIAL TOOL 6801
2 ± PROBING END
8W - 01 - 8 8W - 01 GENERAL INFORMATIONPL
DESCRIPTION AND OPERATION (Continued)

CAUTION: Do not drive cup plug into the casting
as restricted cooling can result and cause serious
engine problems.
INSTALLATION
Thoroughly clean all debris/rust from inside of cup
plug hole in cylinder block or head. Be sure to
remove old sealer. Lightly coat inside of cup plug hole
with MopartStud and Bearing Mount Adhesive.
Make certain the new plug is cleaned of all oil or
grease. Using a proper driver, 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. 3).
It is not necessary to wait for curing of the sealant.
The cooling system can be refilled and the vehicle
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 it's
optimum performance level to maintain fuel economy
and lowest vehicle emissions. If vehicle is not operat-ing to these standards, refer to Engine Diagnosis in
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 in this section.
(4) Clean or replace spark plugs as necessary and
adjust gap as specified in Group 8D, Ignition System.
Tighten to specifications.
(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. Refer to
Group 25, Emission Control Systems.
(10) Road test vehicle as a final test.HONING CYLINDER BORES
(1) Used carefully, the cylinder bore resizing hone,
recommended tool C-823 or equivalent, equipped
with 220 grit stones, is the best tool for this honing
procedure. 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
Fig. 2 Access Plug
1 ± CRANKSHAFT BOLT ACCESS PLUG
2 ± RIGHT MOUNT BOLT ACCESS PLUG
3 ± FASCIA
4 ± SPLASH SHIELD
Fig. 3 Core Hole Plug Removal
1 ± CYLINDER BLOCK
2 ± REMOVE PLUG WITH PLIERS
3 ± STRIKE HERE WITH HAMMER
4 ± DRIFT PUNCH
5 ± CUP PLUG
PLENGINE 9 - 3
GENERAL INFORMATION (Continued)

²When checking #2 main bearing shim #1 & #3
main bearing.
²When checking #3 main bearing shim #2 & #4
main bearing.
²When checking #4 main bearing shim #3 main
bearing.
NOTE: REMOVE ALL SHIMS BEFORE REASSEM-
BLING ENGINE
ALTERNATIVE METHOD
The weight of the crankshaft can be supported by a
jack under the counterweight adjacent to the bearing
being checked.
PLASTIGAGE PROCEDURE
(1) Remove oil film from surface to be checked.
Plastigage is soluble in oil.
(2) Place a piece of Plastigage across the entire
width of the bearing shell in the cap approximately
6.35 mm (1/4 in.) off center and away from the oil
holes (Fig. 5). (In addition, suspected areas can be
checked by placing the Plastigage in the suspected
area). Torque the bearing cap bolts of the bearing
being checked to the proper specifications.
(3) Remove the bearing cap and compare the width
of the flattened Plastigage (Fig. 6) with the metric
scale provided on the package. Locate the band clos-
est to the same width. This band shows the amount
of clearance in thousandths of a millimeter. Differ-
ences in readings between the ends indicate the
amount of taper present. Record all readings taken.
Refer to Engine Specifications.Plastigage gener-
ally is accompanied by two scales. One scale is
in inches, the other is a metric scale.
NOTE: Plastigage is available in a variety of clear-
ance ranges. Use the most appropriate range for
the specifications you are checking.
CONNECTING ROD BEARING CLEARANCE
Engine connecting rod bearing clearances can be
determined by use of Plastigage or equivalent. Thefollowing is the recommended procedure for the use
of Plastigage:
(1) Rotate the crankshaft until the connecting rod
to be checked is at the bottom of its stroke.
(2) Remove oil film from surface to be checked.
Plastigage is soluble in oil.
(3) Place a piece of Plastigage across the entire
width of the bearing shell in the bearing cap approx-
imately 6.35 mm (1/4 in.) off center and away from
the oil hole (Fig. 5). In addition, suspect areas can be
checked by placing plastigage in that area.
(4) Assemble the rod cap with Plastigage in place.
Tighten the rod cap to the specified torque.Do not
rotate the crankshaft while assembling the cap
or the Plastigage may be smeared, giving inac-
curate results.
(5) Remove the bearing cap and compare the width
of the flattened Plastigage (Fig. 6) with the scale pro-
vided on the package. Locate the band closest to the
same width. This band indicates the amount of oil
clearance. Differences in readings between the ends
indicate the amount of taper present. Record all
readings taken. Refer to Engine Specifications.Plas-
tigage generally is accompanied by two scales.
One scale is in inches, the other is a metric
scale. If the bearing clearance exceeds wear
limit specification, replace the bearing.
REPAIR OF DAMAGED OR WORN THREADS
Damaged or worn threads (including aluminum
head spark plug threads) can be repaired. Essen-
tially, this repair consists of drilling out worn or
damaged threads, tapping the hole with a special
Heli-Coil Tap, (or equivalent) and installing an insert
into the tapped hole. This brings the hole back to its
original thread size.
CAUTION: Be sure that the tapped holes maintain
the original centerline.
Heli-Coil tools and inserts are readily available
from automotive parts jobbers.
HYDROSTATIC LOCKED ENGINE
When an engine is suspected to be hydrostatically
locked, regardless of what caused the problem, the
following steps should be used.
CAUTION: DO NOT use starter motor to rotate the
engine, severe damage may occur.
(1) Inspect air cleaner, induction system and
intake manifold to insure system is dry and clear of
foreign material.
(2) Remove negative battery cable.
(3) Place a shop towel around the spark plugs
when removing them from the engine. This will catch
Fig. 6 Clearance Measurement
PLENGINE 9 - 5
GENERAL INFORMATION (Continued)

any fluid that may possibly be in the cylinder under
pressure.
(4) With all spark plugs removed, rotate engine
crankshaft using a breaker bar and socket.
(5) Identify the fluid in the cylinder(s) (i.e., cool-
ant, fuel, oil or other).
(6) Make sure all fluid has been removed from the
cylinders. Inspect engine for damage (i.e., connecting
rods, pistons, valves, etc.).
(7) Repair engine or components as necessary to
prevent this problem from re-occurring.
CAUTION: Squirt approximately one teaspoon of oil
into the cylinders, rotate engine to lubricate the cyl-
inder walls to prevent damage on restart.
(8) Install new spark plugs.
(9) Drain engine oil and remove oil filter.
(10) Fill engine with specified amount of approved
oil and install new oil filter.
(11) Connect negative battery cable.
(12) Start engine and check for any leaks.
CHECKING ENGINE OIL LEVEL
The best time to check engine oil level is after it
has sat overnight, or if the engine has been running,allow the engine to be shut off for at least 5 minutes
before checking oil level.
Checking the oil while the vehicle is on level
ground will improve the accuracy of the oil level
reading. Remove dipstick (Fig. 7) and observe oil
level. Add oil only when the level is at or below the
ADD mark (Fig. 8).
Fig. 7 Dipstick and Engine Oil Fill Locations
1 ± ENGINE OIL FILL
2 ± ENGINE COOLANT RECOVERY CONTAINER3 ± ENGINE OIL DIPSTICK
4 ± COOLING SYSTEM PRESSURE CAP
Fig. 8 Oil Level
1 ± ENGINE OIL LEVEL DIPSTICK
9 - 6 ENGINEPL
GENERAL INFORMATION (Continued)

ENGINE DIAGNOSIS
TABLE OF CONTENTS
page page
DIAGNOSIS AND TESTING
GENERAL INFORMATION...................8
INTAKE MANIFOLD LEAKAGE DIAGNOSIS......8
CYLINDER COMPRESSION PRESSURE TEST . . . 8
CYLINDER COMBUSTION PRESSURE
LEAKAGE TEST.........................9LASH ADJUSTER (TAPPET) NOISE
DIAGNOSIS............................9
ENGINE OIL LEAK INSPECTION..............9
ENGINE DIAGNOSISÐPERFORMANCE........11
ENGINE DIAGNOSISÐMECHANICAL.........12
DIAGNOSIS AND TESTING
GENERAL INFORMATION
Engine diagnosis is helpful in determining the
causes of malfunctions not detected and remedied by
routine maintenance.
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 engine RPM'S change, the area of the sus-
pected 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 (689 kPa)
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
9 - 8 ENGINEPL

should not be disassembled to determine the
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, 1,379kPa (200 psi) maximum, with 552 kPa (80 psi) rec-
ommended.
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 per cylinder.
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 rocker arms (sohc) or lash
adjuster (dohc) and replace.
ENGINE OIL LEAK INSPECTION
Begin with a thorough 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.
(2) Add an oil soluble dye (use as recommended by
manufacturer). Start the engine and let idle for
approximately 15 minutes. Check the oil dipstick to
PLENGINE 9 - 9
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. 3. Test starting system. Refer to
Group 8B, Starting.
4. Faulty coil(s) or control unit. 4. Test and replace as needed.
Refer to Group 8D, Ignition System.
5. Incorrect spark plug gap. 5. Set gap. Refer to Group 8D,
Ignition System.
6. Contamination in fuel system. 6. Clean system and replace fuel
filter.
7. Faulty fuel pump. 7. Test fuel pump and replace as
needed. Refer to Group 14, Fuel
System.
8. Incorrect engine timing. 8. Check for a skipped timing
belt/chain.
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.
4. Faulty coil(s). 4. 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 coil(s). 9. Test and replace as necessary.
Refer to Group 8D, Ignition System.
PLENGINE 9 - 11
DIAGNOSIS AND TESTING (Continued)