1988 PONTIAC FIERO Service Repair Manual

8D3-2 CHARGING SYSTEM
Fig. 1 F CS Charging System Wiring Diagram 1-CARBON
PILE %-GENERATOR
2-VOLTMETER
6-BATTERY
3-RESISTOR 7-CONNECT RESISTOR
4-TEST AM METE^ TO "L" TERMINAL G20197-6D
Fig. 1 H Generator Bench Check - CS
4. If voltage is below 16.0 volts, increase speed and 5. If output is within 15 amperes of rated output,
adjust carbon pile to obtain maximum amperage generator
is good.
output. Maintain voltage above 13.0 volts.
6. If output is not within
15 amperes of rated
output, generator is defective and requires repair.
ON-CAR SERVICE

CHARGING SYSTEM 6D3-3
1. GENERATOR 3. BRACKET
4. SUPPORT
Fig.
60 1 Generator Mountings
SPECIFICATIONS
ENGINE EQUIPMENT GEN/MOD AMP
LB8 H-H/HBL 1101 139/CS130 85A
A-A/HBL 1101 140/CS130 1 OOA
LB9lL98 H-H/HBL-A-A/HBL 1 101 255lCS 130 105A
LO3 H-HIHBL 1101253lCS130 85A
A-AIHBL 1101254lCS130 1 OOA

6D3-4 CHARGING SYSTEM
CS130 GENERATOR DISASSEMBLY, TEST AND REASSEMBLY
(GENERATOR REMOVED FROM ENGINE)
THRU-BOLT LOCATION TESTING STATOR
BOLT (3) TERMINALS IdS## tdFI# llLll Idpd
1. Make scribe marks on end frames to facilitate reas-
sembly.
2. Remove thru-bolts and separate end frames. 3. Punch out cover rivets, or pins, and remove cover on
slip ring end frame.
END FRAME VIEW
PUNCH OUT
LEADS FROM
COVER
RIVE
4. Unsolder stator leads at three terminals on rectifier
bridge. Avoid excessive heat, which could damage
diodes in rectifier bridge. NOTICE: If stator leads are
welded, in place of soldered, cut stator leads about
half way back on rectifier bridge terminals.
5. Remove stator. 6. Drive out three baffle pins and remove baffle from
inside of slip ring end frame. 7. Check stator
for grounds with ohmmeter. If
readlng IS
low, replace stator.
8. Check rotor for grounds with ohmmeter. Check can
be made with drive end frame assembled. Reading
should be very high. If not, replace rotor. Hold rotor
with hex wrench in shaft when removing shaft nut.
9. Check rotor for opens and shorts. Should read 1.7-
2.3 ohms. If not, replace rotor.
Fig. 602 CS 130 Generator Disassembly, Test and Reassembly 1 of 3

CHARGING SYSTEM 6D3-5
REMOVE BRUSH HOLDER,
REGULATOR AND RECTIFIER
"BAT" MOUNTING
TERMINAL SCREWS VEGULATOR I
RECTI~IER BRIDGE I
10. Remove brush holder screw, disconnect terminal
and remove brush holder assembly. If brushes are
to be reused, clean with a soft dry cloth and use
reta~nlng pin to hold brushes In holder
11 Unsolder and pry open termlnal between regulator
and
rectif~er br~dge Remove termlnal and attaching screws to remove regulator and rect~fier br~dge from
end frame
TESTING RECTIFIER BRIDGE
OHMMETER WoHMMETER
12. To check rectifier bridge, connect ohmmeter using
low scale to one terminal and heat sink (step 1).
Reverse leads. If both readings are the same, re-
place rectifier bridge. Check other two diodes in
same manner as step
1. NOTICE: Some digital
ohmmeters cannot be used to check diodes in
bridge. Consult ohmmeter manufacturer to deter-
mine tester capabilities.
13. Check remaining three diodes in same manner by
connecting ohmmeter from each terminal to base
plate (step
2). If both readings are the same on any
diode, replace rectifier bridge.
DRIVE END BEARING
END FRAME
FAN
CROSS SECTION
DE FRAME CS-130
14. Note stack up of parts for drive end bearing assem-
bly. Hold rotor with hex wrench to remove, or
tighten shaft nut. Torque to 54-108
N*m (40-80 Ib.-
ft.).
Fig. 603 CS 130 Generator Disassembly, Test and Reassembly 2 of 3
A

SLIP RING END FRAME BEARING
BEAR~NG RECESSED
IN CASTING
15. lnstall new tolerance ring inside of slip ring end
frame.
16. Press outer race of new bearing against bottom of
end frame casting.
17. Assemble brush holder using insulated screw to
end frame; position holder so brushes will ride
squarely on commutator. Use retainer pin to hold
brushes in holder.
18. Assemble rectifier bridge to end frame using sili-
cone grease (to dissipate heat) between bridge and
end frame. Securely crimp the electrical connection
between bridge and brush holder.
19. Install regulator, crimp and solder connection be-
tween regulator and bridge.
20. lnstall new baffle. Use punch to drive pins down
flush with baffle.
21. Install stator, solder and crimp to three connectors
on bridge. Avoid excessive heat which could dam-
age
d~odes In rect~f~er br~dge 22 Install outsrde cover uslng punch to drlve plns down
flush w~th cover
23 To assemble drlve end frame and rotor assembly tnto end frame, push on both Inner and outer race
to push
slrp rlng end assembly over shaft Then
push on both
Inner and outer race untll outer race IS recessed 1 9-2 2 mm lns~de end frame castrng 24 Assemble three bolts and remove brush retalnlng pin.
020214-6D
Fig. 604 CS 130 Generator Disassembly, Test and Reassembly 3 of 3

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