1988 PONTIAC FIERO ignition

CRANKING SYSTEM CD2-1
CRANK NG SYSTEM
General Description ................................. 6D2-1 Service Procedures .................................. 6D2-3
Cranking System ......................... ... ........ 6D2- 1 Cranking
System ..................... .. ............. 6D2-3
Starter Motor ............................................. 6D2-1 On-Car Service ....................................... 6D2-4 Solenoid .................................................. 6D2- 1
Starter ........................... ... ...................... 6D2-4 Diagnosis ..................................................... 6D2-1 Specifications ............................................. 6D2- I I Cranking System ......................... ... ...... 6D2- 1
Unit Repair ............................................ 6D2-6- 1 1
GENERAL DESCRIPTION
The engine electrical system includes the battery, Battery: To determine the condition of the
ignition (primary and secondary), starter (and related battery,
follow the testing procedure outlined in the
wiring) and the generator (and related wiring). Battery section
(6D1).
Diagnostic charts (see Section 6D) will aid in Wiring: Inspect the wiring for damage. Inspect trouble-shooting system faults. When a fault is traced all connections to the cranking motor, solenoid, to a articular component, refer to that components' ignition switch and battery, including all ground
section of the service manual.
connections. Clean and tighten all connections, as
CRANKING SYSTEM
The cranking circuit consists of the battery,
starting motor, ignition switch, and related electrical
wiring. These components are connected electrically as
shown in Fig. 1.
Starter Motor
Wound field starter motors have pole pieces,
arranged around the armature, that are energized by
wound field coils.
Solenoid
Enclosed shift lever cranking motors have the
shift lever mechanism and the solenoid plunger
enclosed in the drive housing, protecting them from
exposure to dirt, icing conditions and splash.
In the basic circuit shown in Fig. 1, solenoid
windings are energized when the switch is closed. The
resulting plunger and shift lever movement causes the
pinion to engage the engine flywheel ring gear and the
solenoid main contacts to close, and cranking takes
place. When the engine starts, pinion overrun protects
the armature from excessive speed until the switch is
opened, at which time the return spring causes the
pinion to disengage. To prevent excessive overrun, the
switch should open immediately when the engine
starts.
DIAGNOSIS
CRANKING SYSTEM
Before removing any unit in a cranking circuit for
repair, the following checks should be made:
Electrical System General Diagnosis:
Follow the procedures shown in Section 6D to isolate
problem. required.
Solenoid
and Ignition Switch: Inspect all
switches to determine their condition.
Starter Motor Noise: To correct starter motor
noise during starting, use the following procedure:
1. Refer to Fig. 2 to determine the problem.
2. If the complaint is noise, correction can be
achieved by proper "shimming" as follows:
a. Check
flywheel for damage
- bent flywheel,
unusual wear, etc.
b. Start
engine and carefully touch outside
diameter of rotating flywheel ring gear with
chalk or crayon to show high point of tooth
runout. Turn engine off and rotate flywheel
so that the marked teeth are in the area of
the starter pinion gear.
c. Disconnect negative battery cable to
prevent cranking of engine.
d. Check pinion to flywheel clearance, as
shown in Fig. 3, by using a wire gage of
.5mm (.02OU) minimum thickness (or
diameter). Center a pinion tooth between
two flywheel teeth and gage, as shown in
Fig. 3. Do not gage in the corners, where a
misleading larger dimension may be
observed. If the clearance is under this
minimum, shimming the starter away from
the flywheel is required.
e. If
the clearance is grossly over
.5mm (.02OU)
in the vicinity of 1.5mm (.06OU) or more,
shimming the starter toward the flywheel is
required. (This is generally the problem
causing broken flywheel teeth or starter
housings.) Shimming the starter toward the
flywheel can be accomplished by shimming
only the outboard starter mounting pad.
A
shim of .4mm (.015") thickness, at this

CHARGING SYSTEM 6D3-1
SECTION 6D3
CHARG NG SYSTEM
CONTENTS
General Description ................................. 6D3- 1 Charging System ........................................ 6D3- 1
.......................................... Charging System - CS ............................... 6D3- 1 On-Car Service 6D3-2
................................................... Diagnosis .. 6D3- 1 Generator 6D3-3 ...................... ......................... ............................................. 6D3- 1 Specifications 6D3-3 Service Procedures .................................. Unit Repair .. 6D3-4-6 ............................... ............
GENERAL DESCRIPTION
The engine electrical system includes the battery,
ignition (primary and secondary), starter (and related
wiring) and the generator (and related wiring).
Diagnostic charts (see Section 6D) will aid in
trouble-shooting system faults. When a fault is traced
to a particular component, refer to that components'
section of the service manual.
CHARGING SYSTEM-CS
The CS Charging System has several sizes
available, including the CS-130 and CS-144. The
number (130 or 144) denotes the
OD in mm of the
stator laminations.
CS generators use a new type regulator and a
diode trio is not used. A delta stator, rectifier bridge,
and rotor with slip rings and brushes are electrically
similar to earlier generators. A conventional pulley and
fan is used and, on the CS-130, an internal fan cools the
slip ring end frame, rectifier bridge and regulator.
Unlike three-wire generators, the CS-130 and
CS-144 may be used with only two connections
-
battery positive and an "L" terminal to the charge
indicator bulb. Use of "P",
"F", and "S" terminals is
optional. The "P" terminal is connected to the stator,
and may be connected externally to
a tachometer or other
device. The
"F" terminal is connected internally
to field positive, and may be used as a fault indicator.
The "S" terminal may be connected externally to a
voltage, such as battery voltage, to sense voltage to be
controlled.
As on other charging systems, the charge
indicator lights when the switch is closed, and goes out
when the engine is running. If the charge indicator is
on with the engine running, a charging system defect
is indicated. For all kinds of defects, the indicator will
glow at full brilliance, not "half lit". Also, the charge
indicator will be on with the engine running if system
voltage is too high or too low. The regulator voltage
setting varies with temperature, and limits system
voltage by controlling rotor field current.
This regulator switches rotor field current on and
off at a fixed frequency of about 400 cycles per second.
By varying the on-off time, correct average field
current for proper system voltage control is obtained.
At high speeds, the on-time may be 10% and the
off-time 90%. At low speeds, with high electrical loads,
on-off time may be 90% and
lo%, respectively.
No periodic maintenance on the generator is
required.
DIAGNOSIS
SERVICE PROCEDURES
CHARGING SYSTEM
The generator does not require periodic
lubrication. The rotor shaft is mounted on ball bearings
at the drive end and roller bearings at the slip ring end.
Each contains a permanent grease supply. At periodic
intervals, check mounting bolts for tightness and adjust
belt tension (see Section
6B), if applicable.
e When adjusting belt tension, apply pressure at
center of generator, never against either end
frame.
GENERATOR BENCH CHECK-CS
To check generator in a test stand, remove as
specified in On-Car Service and proceed as follows: 1.
Make connections as shown in Figure
lH, except
leave the carbon pile disconnected. The ground
polarity of generator and battery must be the
same. The battery must be fully charged. Use a
30-500
OHM resistor between battery and "L"
terminal.
2. Slowly increase generator speed and observe
voltage.
3. If the voltage is uncontrolled and increases above
16.0 volts, the rotor field is shorted, the regulator
is defective, or both.
A shorted rotor field coil can
cause the regulator to become defective. NOTE:
The battery must be fully charged when making
this test.

IGNITION SYSTEM 6D4-1
ON SYSTEM
CONTENTS
General Description ............................... 6D4-1 Service Procedures ............................. 6D4-3
Ignition System .......................................... 6D4-1
Ignition System .......................................... 6D4-3
Distributor Ignition ................................ 6D4-1
Distributor Ignition ................................ 6D4 -3
Diannosis .................................................... 6D4-3 On-Car Service ......................................... 6D4-5 -
Ignition System .......................................... (334-3 Ignition System ........................... .. .............. 6D4-5
Distributor ................................................. 6D4 -7 HE1 Distributor .................................... 6D4-3
GENERAL DESCRIPION
The engine electrical system includes the battery,
ignition (primary and secondary), starter (and related
wiring) and the generator (and related wiring).
Diagnostic charts (see Section 6D) will aid in
trouble-shooting system faults. When a fault is traced
to a particular component, refer to that components'
section of the service manual.
IGNITION SYSTEM
Distributor Ignition
The ignition circuit consists of the battery,
distributor, ignition switch, spark plugs and primary
and secondary wiring. Refer to the Battery portion of
this section for battery information.
PIE1 Distributor
The Nigh Energy Ignition (HEI) distributor with
Electronic Spark Timing (EST), used on most engines,
combines all ignition components in one unit. The
ignition coil is in the distributor cap and connects
through a resistance brush to the rotor.
The distributor has an internal magnetic pick-up
assembly which contains a permanent magnet, a pole
piece with internal teeth and a pick-up coil. When the
teeth of the timer core, rotating inside the pole piece,
line up with the teeth of the pole piece, an induced
voltage in the pick-up coil signals the electronic module
to trigger the coil primary circuit. The primary current
decreases and a high voltage is induced in the ignition
coil secondary winding. This voltage is directed
through the rotor and secondary leads to fire the spark
plugs. The capacitor in the distributor is for radio noise
suppression,
All spark timing changes in the
HE1 (EST)
distributor are done electronically by an Electronic
Control Module (ECM), which monitors information
from various engine sensors, computes the desired
spark timing and signals the distributor to change the
timing accordingly.
A back-up spark advance system
is incorporated to signal the ignition module in case of
(ECM) failure. No vacuum or mechanical advance is
used. Further (EST) information is found in sections 6E
Emissions Control, and
8A Electrical
Troubleshooting.
Ignition Timing
Timing specifications for each engine are listed in
Section
6E. When using a timing light, connect an
adapter between the No. 1 spark plug and the No. 1
spark plug wire, or use an inductive type pick-up.
Do
not pierce the plug lead.
Once the insulation of the
spark plug cable has been broken, voltage will jump to
the nearest ground, and the spark plug will not fire
properly.
Always follow the tune-up label
procedures when adjusting timing.
Some engines will incorporate a magnetic timing
probe hole for use with special electronic timing
equipment. Fig.
1A shows a typical magnetic probe
hole. Consult manufacturer's instructions for use of
this equipment.
Secondary Wiring
The spark plug wiring used with ignition systems
is a carbon impregnated cord conductor, encased in an
8MM (5/16") diameter silicone rubber jacket. The
silicone jacket withstands very high temperatures and
also provides an excellent insulator for the higher
voltage of the
HE1 system. Silicone spark plug boots
form a tight seal on the plug.
The boot should be
twisted 1/2 turn before removing. Care should
also be exercised when connecting a timing light or
other pick-up equipment. Do not force anything
between the boot and wiring, or through the silicone
jacket. Connections should be made in parallel using
an adapter. DO NOT pull on the wire to remove. Pull
on the boot, or use a tool designed for this purpose.
Spark Plugs
Resistor type, tapered seat spark plugs are used
on all engines (except aluminum heads). No gasket is
used on these tapered seat plugs. See Figs.
1B and 1C
for an explanation of coding on spark plugs.
Normal service is assumed to be a mixture of
idling, slow speed, and high speed driving. Occasional
or intermittent high-speed driving is needed for good

604-2 IGNITION SYSTEM
1-wACITm
2-7-TERNUNAL
ASSUVlBLY
4-TO Em
CONNECTOR
5-ODVER
8-WOMR
9- ING
Fig. 1 HE1 (EST) Distributor
2- "0" STAMP O
3-NOTCH IN PULLEY
4-MAGNETIC
TIMING
PROBE HOLE ASM.
5-PULLEY
6-ASM. MOUNTED TO
FRONT COVER
Fig. 1A Magnetic Timing Probe Hole
PREFIX ANDSUFFIX
LETTERS IDENTIFY
A SPECIFIC TYPE
SPARK PLUG. NUMBERS
RELATE TO THREAD
SlZE AND HEAT RANGE
AS FOLLOWS:
R = Resistor
4 = 14 mm Thread
6 = Heat Range
T
= Taper Seat
S
= Extended Tip
TAPERED SEAT NO GASKET
G20199-6D
Fig. 1 B Spark Plug Example
1st number denotes THREAD SlZE
4 = 14 mm 2 = %-inch taper
8 = 18mm 5 = %-inch
10 = 10 mm 6 = %-inch
12
= 12 mm 7 = Ve-inch
2nd number denotes HEAT RANGE
0-1-2-3-4-5-6-7-8-9
COLD
- HOT
Fig. 1 C Spark Plug Coding
spark plug performance. It gives increased combustion
heat, burning away carbon or oxides that have built up
from frequent idling, or continual stop-and-go driving.
Spark plugs are protected by an insulating nipple made
of special heat-resistant material, which covers the
spark plug terminal and extends downward over
a
portion of the plug insulator. These nipples prevent

IGNITION SYSTEM 6B4-3
flash-over, which causes engine misfiring. Do not
mistake corona discharge for flash-over, or a shorted
insulator. Corona is a steady blue light appearing
around the insulator, just above the shell crimp. It is
the visible evidence of a high-tension field and has no
effect on ignition performance. Usually it can be
detected only in darkness. This discharge may repel
dust particles, leaving a clear ring on the insulator just
above the shell. This ring is sometimes mistakenly
regarded as evidence that combustion gases have blown
out between shell and insulator.
lgnition Switch
The mechanical switch is located in the steering
column on the right hand side just below the steering
wheel. The electrical switching portion of the assembly
is separate from the key and lock cylinder. However,
both are synchronized and work in conjunction with
each other through the action of the actuator rod
assembly.
For a complete explanation of the key and lock
cylinder, and the actuator rod assembly, see
STEERING, Section
38. See Section 8 for electrical
switching.
DIAGNOSIS
IGNITION SYSTEM
Spark Plugs
Worn or dirty plugs may give satisfactory
operation at idling speed, but at higher RPM they
frequently fail. Faulty plugs are indicated in a number
of ways: poor fuel economy, power loss, loss of speed,
hard starting and generally poor engine performance.
Spark plugs may also fail due to carbon fouling,
excessive gap, or a broken insulator. Fouled plugs may
be indicated by black carbon
deposits. The black deposits are usually the result of
slow-speed driving and short runs, where sufficient
engine operating temperature is seldom reached. Worn
pistons, rings, faulty ignition, over-rich carburetion
and spark plugs which are too cold will also result in
carbon deposits.
Excessive gap wear, on plugs of low mileage,
usually indicates the engine is operating at high speeds,
or loads that are consistently greater than normal, or
that a plug which is too hot is being used. Electrode
wear may also be the result of plug overheating,
causcd
by combustion gases leaking past the threads due to
insufficient torquing of the spark plug. Excessively lean
carburetion will also result in accelerated electrode
wear.
Broken insulators are usually the result of
improper installation, or carelessness when regapping
the plug. Broken upper insulators usually result from
a poor fitting wrench, or an outside blow. The cracked
insulator may not show up right away, but will as soon
as oil or moisture penetrates the crack. The crack is
usually just below the crimped part of shell and may
not be visible.
Broken lower insulators usually result from
carelessness when regapping and generally are visible.
This type of break may result from the plug operating
too "hot", which may happen in periods of high-speed
operation or under heavy loads. When regapping a
spark plug, always make the gap adjustment by
bending the ground (side) electrode. Spark plugs with
broken insulators should always be replaced.
HE1 Distributor
See Unit Repair for distributor disassembly, test
and reassembly of individual distributor components,
when the distributor is removed from the vehicle. See
On-Car Service for distributor removal and installation
and for component removal with distributor in car. See
Section 6E for
HE1 and EST diagnosis.
SERVICE PROCEDURES
IGNITION SYSTEM
Distributor Ignition
NOTICE: This procedure is generally true for
most carlines. Where procedure is different, or
where additional information is required, see
"ON-CAR SERVICE" for specific
carline.
HE1 DISTRIBUTOR
Service Precautions
1. When making compression checks, disconnect
the ignition switch feed wire at the distributor.
When disconnecting this connector,
do not use
a screwdriver or tool to release the locking tab, as
it may break.
2. No periodic lubrication is required. Engine oil
lubricates the lower bushing and an oil-filled
reservoir provides lubrication for the upper
bushing. 3.
The tachometer (TACH) terminal is next to the
ignition switch (BAT) connector on the
distributor cap.
NOTICE: The tachometer terminal must
NEVER be allowed to touch ground, as damage
to the module and/or ignition coil can result.
Some tachometers currently in use may NOT be
compatible with the High Energy Ignition System.
Consult the manufacturer of the tachometer if
questions arise.
4. Dwell adjustment is controlled by the module,
and cannot be adjusted.
5. The material used to construct the spark plug
cables is very soft. This cable will withstand more
heat and carry a higher voltage, but scuffing and
cutting become easier. The spark plug cables
must be routed correctly to prevent
chafing or
cutting. See Spark Plug Section. When removing

684.4 IGNITION SYSTEM
a spark plug wire from a spark plug, twist the 4. Do not wipe grease from module, or distributor
boot on the spark plug and pull
on the boot to base,
if same module is to be replaced.
remove the wire, or use a special tool designed to
remove spark plug boots.
Install or Connect
Remove or Disconnect
1. Ignition switch battery feed wire and tachometer
lead (if equipped) from distributor cap. Also
release the coil connectors from the cap. (DO
NOT use a screwdriver or tool to release the
locking tabs.)
2. Distributor cap by turning four screws
counterclockwise. Move cap out of the way.
3. Four-terminal ECM harness from distributor.
4. If necessary, remove secondary wires from cap,
release wiring harness latches and remove wiring
harness retainer. The spark plug wire numbers
are indicated on the retainer.
5. Distributor clamp screw and hold-down clamp.
6. Note position of rotor, then pull distributor up
until rotor just stops turning counterclockwise
and again note position of rotor.
To insure correct timing of the distributor,
the distributor must be INSTALLED with
the rotor correctly positioned as noted.
If the engine was accidentally cranked after the
distributor was removed, the following procedure can
be used for installing:
1. Remove No. 1 spark plug.
2. Place finger over No. 1 spark plug hole and crank
engine slowly until compression is felt.
3. Align timing mark on pulley to "0" on engine
timing indicator.
4. Turn rotor to point between No. 1 and No. 8
spark plug towers on distributor cap on V8
engines, between No. 1 and No. 6 on V6 engines,
and No.
1 and No. 4 on 4 cylinder engines.
5. Install distributor and connect ignition feed wire.
6. Install distributor cap and spark plug wires.
7. Check engine timing (see Set Ignition Timing).
Install or Connect
1. Insert distributor, positioning rotor as removed.
2. Distributor hold-down clamp and screw.
3. Wiring harness retainer and secondary wires, if
removed.
4. ECM harness connector.
5. Distributor cap.
6. Coil connectors.
7. Battery wire and tachometer lead, if equipped.
Module
It is not necessary to remove the distributor from
car.
Remove or Disconnect
1. Distributor cap and rotor.
2. Two module attaching screws, and lift module
UP. 3. Leads from module. (Observe color code on leads
as these cannot be interchanged.)
NOTICE: If a new module is to be installed, a
package of silicone grease will be included with it.
Spread the grease on the metal face of the module
and on the distributor base where the module
seats. This grease is necessary for module cooling.
1. Module.
2. Module leads (observe color code).
3. Attaching screws to module.
4. Rotor.
5. Cap.
Pick-Up Coil
1. Remove distributor from car and follow
instructions in Unit Repair, as applicable.
Rotor
Fig. 1
1. Remove distributor cap.
2. The rotor is retained by two screws and is
provided with a slot which fits over a square lug,
,
so that the rotor can be installed in only one
position.
Integral Ignition Coil
Fig. I
Remove or Disconnect
1. Distributor cap.
2. Three coil cover attaching screws, and lift off
cover.
3. Coil attaching screws and lift ignition coil and
leads from cap.
Install or Connect I
1. Coil and attaching screws.
2. Coil leads.
3. Coil cover and attaching screws.
Capacitor
Fig. 1
The capacitor is part of the coil wire harness
assembly. Since the capacitor is used only for radio
noise suppression, it will seldom need replacement.
Remove or Disconnect I
1. Distributor cap and rotor.
2. Capacitor attaching screw and unplug connector
from module. It may help to loosen the module.
Install or Connect I
1. Plug into module.
2. Capacitor and hold-down screw (be sure ground
lead is under screw).

IGNITION SYSTEM 6014.5
3. Rotor and cap. 4. Turn off the engine and remove the timing light.
Reconnect the number one spark plug wire, if
Set Ignition Timing removed.
Spark Plug Wires 1. Refer to the tune-up label located in the engine
compartment. Follow all instructions on the Use
care when removing spark plug wire boots
label. from
spark plugs. Twist the boot
1/2 turn before
removing and pull on the
boot only to remove the
With ignition off, connect the pick-up lead of
timing light to the number one spark plug. Use
a jumper lead between the wire and plug, or an
inductive type pick-up.
DO NOT pierce the wire,
or attempt to insert a wire between the boot and
the wire. Connect the timing light power leads
according to manufacturer's instructions.
Start the engine and aim the timing light at the
timing mark. The line on the balancer or pulley
will line up at the timing mark. If a change is
necessary, loosen the distributor hold-down
clamp bolt at the base of the distributor. While
observing the mark with the timing light, slighty
rotate the distributor until the line indicates the
correct timing. Tighten the hold-down bolt and
re-check the timing. wire.
When replacing plug wires, route the wires
correctly and through the proper retainers. Failure to
route the wires properly can lead to radio ignition noise
and crossfiring of the plugs, or shorting of the leads to
ground.
Special care should be exercised when reinstalling
spark plug boots, to assure that the metal terminal
within the boot is fully seated on the spark plug
terminal and that the boot has not moved on the wire.
If boot to wire movement has occurred, the boot will
give a false visual impression of being fully seated.
A
good check to assure that boots have been properly
assembled is to push sideways on the installed boots.
If they have been correctly installed, a stiff boot, with
only slight looseness, will be noted. If the terminal has
not been properly seated on the spark plug, only the
resistance of the rubber boot will be felt when pushing
sideways.
ON-CAR SERVICE
I I -COI L & BRACKET ASM. 2-DISTRIBUTOR 3-COIL WIRE I
Fig. 601 Distributor and Coil - LB8

6D4-6 IGNITION SYSTEM
LEFT
1-COIL WIRE
2-DISTRIBUTOR
3-CO
I L
Fig.
602 Distributor and Coil - V8 (Typical)