PONTIAC FIERO 1988 Service Owner's Manual

OB-4 MAINTENANCE AND LUBRICATION
Tire and wheel operation - Be alert to a vibra-
tion of the steering wheel or seat at normal highway
speeds. This may mean a wheel balance is needed. Also, a
pull right or left on a straight, level road may show the
need for
a tire pressure adjustment or wheel alignment.
Steering system operation - Be alert to
changes in steering action. An inspection is needed when
the steering wheel is harder to turn or has too much free
play or if unusual sounds are noted when turning or
parking.
Headlight aim operation - Take note of light
pattern occasionally. If beam aim doesn't look right,
headlights should be adjusted.
AT EACH FUEL FILL
Engine oil level check - Check engine oil level
and add if necessary. See your Owner's
Manual for further
details.
NOTICE: A large loss in this system may indicate a
problem. Have it inspected and repaired at once.
Engine coolant level and condition - Check
engine coolant level in coolant reservoir tank and add if
necessary. Replace if dirty or rusty. See your Owner's
Manual for further details.
NOTICE: A large loss in this system may indicate a
problem. Have it inspected and repaired at once.
Windshield washer fluid level check -- Check
washer fluid level in container and add if necessary.
Hood latch operation - When opening hood on
cars equipped with hoods that open from the front, note
the operation of secondary latch. It should keep hood from
opening all the way when primary latch is released. Make
sure that hood closes firmly.
AT LEAST MONTI-ILY
Tire and wheel inspection and pressure
check--
Check tires for abnormal wear or damage. Also,
check for damaged wheels. Keep pressures as shown on
Tire Placard on the driver's door (include spare unless it is
a stowaway). Pressure should b\: checked when tires are
"cold". See "Tires" in Owner's Manual for further
infomation.
Light operation check - Check operation of
license plate light, side-marker lights, headlights includ-
ing high beams, parking lights, taillights, brake lights.
turn signals, backup lights, instrument panel and interior
lights and hazard warning flashers.
Fluid leak check - After the car has been parked
for a while, inspect the surface beneath the car for water,
oil, fuel or other fluids. Water dripping from the air
conditioning system after use is normal. If you notice fuel
leaks or fumes, the cause should be found and corrected at
once.
AT LEAST TWICE A YEAR (FOR EXAMPLE,
EVERY SPRING AND FALL)
Power steering pump fluid level check --
Check power steering pump fluid level in accordance with
Owner's Manual instructions and keep at proper level.
NOTICE: A large loss in this system may indicate a
problem. Have it inspected and repaired at once.
Brake master cylinder reservoir fluid level
check ---- Check fluid and keep at proper level. Note: It is
normal for the brake fluid level to go down slightly as the
brake pads wear
- so be sure to keep reservoir filled.
NOTICE: A large loss in this system may indicate a
problem. Have
it inspected and repaired at once.
Clutch system service --- manual transmis-
sionltransaxle --- For cars equipped with hydraulic
clutch system, check the reservoir fluid level and add fluid
as required. All others, check clutch pedal free travel and
adjust as necessary. See your Owner's Manual for further
details.
~
NOTICE: A large loss in this system may indicate a
problem. Have it inspected and repaired at once.
Weatherstrip Lubrication - Clean surface and
then apply a thin film of silicone grease with a clean cloth.
EACH TIME OIL IS CHANGED
Automatic and manual transmissionltrans-
axle fluid level check - Check transmission/transaxle
fluid level and add as required. (Corvette only) if equipped
with manual transmission
- check fluid in the overdrive
unit and add as required.
NOTICE: A large loss in this system may indicate a
problem. Have
it inspected and repaired at once.
Brake systems inspection - For convenience,
the following should be done when wheels are removed
for rotation: Inspect lines and hoses for proper hookup,
binding, leaks, cracks, chafing, etc. Inspect disc brake
pads for wear and rotors for surface condition. Also in-
spect drum brake linings for wear and cracks. Inspect
other brake parts, including drums, wheel cylinders, park-
ing brake, etc. at the same time. Check parking brake
adjustment.
INSPECT BRAKES MORE OFTEN IF DRIVING
HABITS OR CONDITIONS RESULT IN FREQUENT
BRAKING.
Steering, suspension and front drive axle
boot and seal inspection
- Inspect front and rear
suspension and steering system for damaged, loose or
missing parts, signs of wear or lack of lubrication. Inspect
power steering lines and hoses for proper hookup, bind-
ing, leaks, cracks, chafing, etc. (On cars equipped with
manual steering gear, check for seal leakage.) On
front-
wheel-drive cars, clean then inspect drive axle boot seals
for damage, tears or leakage. Replace seals if necessary.
Exhaust system inspection - Inspect complete
system. Inspect body near the exhaust system. Look for
broken, damaged, missing or out-of-position parts as well
as open seams, holes, loose connections or other condi-
tions which could cause a heat buildup in the tloor pan or
could let exhaust fumes seep into the trunk or passenger
compartment.

MAINTENANCE AND LUBRICATION OB-5
Throttle linkage inspection -- Inspect for inter-
ference, binding, damaged or missing parts.
Engine drive belts inspection - Inspect all
belts for cracks, fraying and wear. Adjust or replace as
needed.
Rear axle service (if equipped) - Check gear
lubricant level and add if needed. For cars equipped with a
limited slip rear axle, fluid does not require changing
(except Caprice and Corvette
- change fluid and required
additive at first
7,500 miles (12 500 km). See your
Owner's Manual or "Recommended Fluids
& Lubricants
Chart" in this section.
IF YOU USE YOUR GAR TO PULL A TRAILER,
CHANGE GEAR LUBRICANT EVERY 7,500 MILES
(12 500 KM).
NOTICE: A large loss in this system may indicate a
problem. Have it inspected and repaired at once.
Power antenna - Clean and then lubricate power
antenna mast. The proper lubricant as shown in Figure
OB-2 should be used.
AT LEAST ONCE A YEAR
Lap and shoulder belts condition and opera-
tion
- Inspect belt system, including webbing, buckles,
latch plates, retractors, guide loops and anchors.
Moveable head restraint operation - On cars
with moveable restraints, make sure restraints stay in the
desired position. (See adjustment instructions in your
Owner's Manual.)
Seatback latch and recliner operation on
cars equipped
with recliner seat --- Be sure seat-
backs latch on those cars with folding seats using mechan-
ical latches. Make sure the recliner is holding by pushing
and pulling on the top of the
seatback while it is reclined.
See your Owner's Manual for seat operating information.
Spare tire and jack storage- Be alert to rattles
in rear of car. Make sure the space tire, all jacking equip-
ment, any tire inflator and any covers or doors are securely
stowed at all times. Oil jack ratchet or screw mechanism
after each use.
Key lock service - Lubricate key lock cylinder at
least annually.
Body lubrication service - Lubricate all body
door hinges including the tailgate or hatchback lid (if
equipped). Also lubricate the body hood, fuel door and
rear compartment hinges and latches including interior
glove box and counsel doors, and any folding seat
hardware.
"Fansmissionltransaxle neutral or clutch
starl switch operation
CAUnON: Before pedorming the follow-
ing safety switch check, be sure to have
enough room around the car. Then, firmly
apply both the parking brake (see your
Owner's Manual for procedure) and the
regular brakes. Do not use the accelerator pedal.
If the engine
starls, be ready to turn
off the ignition promptly. Take these pre-
cautions because the car could move
without warning and possibly cause per-
sonal injury or properly damage. On auto-
matic transmissionltransaxle cars, try to
starl the engine in each gear. The starler
should crank only in "Park" or "Neutral."
On manual transmissionltransaxle cars,
place the
shiR lever in "Neutral," push the
clutch halfway and try to starl. The starler
should crank only when the clutch is fully
depressed.
Steering column lock operation
- While
parked, try to turn key to "Lock" in each gear range. The
key should turn to "Lock" only when gear is in "Park" on
automatic or "Reverse" on manual
transmissionltransax-
le. On cars with key release lever, try to turn key toULock"
without depressing the lever. The key should turn to
"Lock" only with the key lever depressed. On all vehicles,
the key should come out only in "Lock."
Parking brake and transmissionltransaxle
"Park" mechanism operation
CAUT1ON:Before checking the holding
ability of the parking brake and automatic
transmissionltransaxle "Park" mecha-
nism, park on a fairly steep hill with
enough room for movement in the down-
hill direction. To reduce the risk of person-
al injury or property damage, be prepared
to apply the regular brakes promptly if the
car begins to move.
To check the parking brake, with the engine running and
transmission/transaxle in "Neutral." slowly remove foot
pressure from the regular brake pedal (until the car is held
by only the parking brake).
To check the automatic transmissionltransaxle "Park"
mechanism holding ability, release all brakes after shift-
ing the transmissionltransaxle to "Park."
ljnderbody flushing - At least every spring,
tlush from the underbody with plain water any corrosive
materials used for ice and snow removal and dust control.
Take care to thoroughly clean any areas where mud and
other debris can collect.
Sediment packed in closed areas
of the vehicle should be loosened before being flushed.
Engine cooling system service - Inspect
coolant and freeze protection. If dirty or rusty, drain, flush
and refill with new coolant. Keep coolant
at the proper
mixture as specified in your Owner's Manual. This pro-
vides proper freeze protection. corrosion inhibitor level
and engine operating temperature. Inspect hoses and re-
place if cracked. swollen or deteriorated. Tighten hose
clamps. Clean outside of radiator and air conditioning
condensor. Wash radiator filler cap and neck.
To help
ensure proper operation. a pressure test of both the cooling
system and cap is also recommended. (See maintenance
schedule charts in Figure
OB-l for the recommended
coolant change interval.)

NOTE: Fluids and lubricants identified below by name, part number or specification may be obtained from your GM dealer.
Figure 00-2 Recommended Fluids and Lubricants
USAGE
Engine
Oil
Engine Coolant
Brake and
Hydraul~c Clutch Systems
Parking Brake Cables
Power Steering System
Manual
Steerlng Gear (reclrculat~ng ball)
Automatic
Transrn~ssionRransaxle and 5 Speed Manual Transm~ss~ons
Manual Transm~ssion (rear-wheel-drive) 4 Speed
Manual
Transm~ss~onRransaxle Shin Linkage
Key Lock Cylinders
Automatic Transmlss~onfrransaxle Shlft Llnkage
Clutch Llnkage Plvot Po~nts
Floor Sh~n L~nkage
Power Antenna Mast (3-mast sect~on-type only)
Chass~s Lubr~cation
Standard D~fferent~al Rear Axle
L~m~ted-Sl~p D~flerent~al Rear Axle
W~ndsh~eld.Washer Solvent
Hood Latch Assembly
a)
Plvots and Sprlng Anchor
b) Release Pawl
Front Wheel Bearings
(rearqwheel-drive)
Hood and door hlnges, statlon wagon tailgate hlnge or hatchback Ild and Ilnkage, headl~ght door assembl~es, statlon wagon rear foldrng seat, fuel door hlnge, rear compartment Ihd hlnges
Weatherstr~ps
FLUlDlLUBRlCANT
GM Goodwrench Motor 011 or equivalent for API Se~lce, SFICC or SFICD of the
recommended v~scos~ty
M~xture of water and good qual~ty ethylene glycol base antllreeze conforming to GM spec 1825M (GM Part No 1052753)
Delco Supreme 11
Fluld (GM Part No 1052535) or DOT-3 Fluld
Chass~s grease meetlng requirements of GM-6031M (GM Part No 1052497)
GM power
steerlng flu~d, Part No 1052884 or equivalent
Use lubricant meetlng requirements of GM-4673M (GM Part No 1052182)
DEXR0N'-II Automat~c Transm~ss~on Flu~d (GM Part No 1051855) Camaro and Flreblrd (5 Speed)
Corvette overdr~ve unlt - DEXRON a.II All others SAE-80W-90 GL-5 gear lubr~cant (GM Part No 1052271)
Chass~s grease meetlng requirements of GM-6031M (GM Part No 1052497)
Black Key Lock
Cyl~nders - light oil (GM Par1 No. 1052949)
All other Key Lock Cyl~nders - sllicone lubrlcant (GM Part No 1052277)
Eng~ne 011
Eng~ne 011
Eng~ne 011
Llght 011 (GM Part No 1052949)
Chass~s grease meetlng requirements of GM-6031M (GM Part No 1052497)
SAE
80W or SAE 80W-90 GL-5 (SAE 80W GL-5 In Canada) gear lubricant (GM Part No
1052271)
For Camaro only
- Use SAE BOW190 GL-5+ Hypold 011 (GM Part No 1050010), 11 equ~pped wl5 7L (L98) Englne or 5 OL (LB9) engine wmpeed manual transm~ss~on and disc brakes
All other applications - Use SAE 80W or SAE 80W-90 GL-5 Gear Lubr~cant (GM Part No
1052271)
GM
Opt~kleen Washer Solvent (GM Part No 1051515) or equ~valent
a) Eng~ne 011 b) Chass~s grease meet~ng requirements of GM.6031M (GM Part No 1052497)
Lubricant GM Part No 1051344 grease or equivalent
Eng~ne 011
S~l~cone Grease (GM Part No 1052863) or equivalent

HEATING AND VENTILATION 1A-1
SECTION 1A
NG AND VENT
CONTENTS
General Description ................................. 1A-1
Diagnosis - Heater Trouble ...................... 1A-5
Insufficient Heating or Defrosting .............. 1A-5
Blower Electrical ......................................... 1A-7
....... Improper Air DeliveryINo Mode Shift 1 A-8
Too Much Heat .......................................... 1A-9 ....................................................... Controls 1A-10 ............................................... Blower Noise 1A-11
....................................... On-Vehicle Sewice 1A-13
.......................... Heater Control Assembly 1 A- 13
....................................... Blower Switch 1A- 13
.................................. Temperature Cable
1 A- 13
.......................................... Heater Core 1 A- 13
................................. Vent Control Cable 1 A- 13
Lower Heater Outlet
................................ 1A-14
........................................ Blower Motor 1A-14
GENERAL DESCRIPTION
The base heater system is designed to provide
heating, ventilation, windshield defrosting and on some
cars, side window defogging. Ram air ventilation is
provided on some cars by two (2) outboard vent valves
installed in the plenum. These vent valves are
controlled by push-pull controls mounted in the
instrument panel. When either of these valves are
opened, air will enter the passenger compartment from
the pressurized plenum and be directed to the floor of
the vehicle.
/& VENTILATION
1-FRONT INLET GRILLE
2-BODY LOCK PILLAR EXHAUST VALVE
Fig. 2 Interior Body Air & Exit - Typical Hatchback Models
The power-vent, heat, and defrost provisions of
the base system are controlled within the heater
module. The module itself is composed of two (2)
components
- a blower air inlet and a heater defroster.
The blower air inlet is mounted to the front of the cowl
and the heater defroster assembly is mounted to the
rear of the cowl. A gasket is used between the two to
prevent air, water and noise entrance into the
passenger compartment. Air distribution is through a
heater outlet, defroster duct, power-vent duct work
and outlets.
The three modes of the base heater system (vent,
heat, defrost) are controlled by the functional
assemblies within the heater module. These assemblies
are defined below:
1. Motor & Fan Assembly (Blower).
Provides and regulates air flow from the air inlet
for further processing and/or distribution.
2. Heater Core.
Transfers heat from engine coolant to inlet air,
heating the inlet air.
3. Temperature Valve.
Regulates the amount of air passing through the
heater core, controlling the temperature and mix
of heated and ambient air.
4. Mode (Defroster) Valve.
Regulates the flow and distribution of processed
air to the distribution (heater or defroster) ducts.
5. Vent Valve.
Regulates the flow of non-processed (outside) air
into the passenger compartment.
The operation of these assemblies is controlled by
the levers and switch on the control head. Depending
on model application, two (2) or three
(3) indexed
snap-in cables are attached to the module and control
levers.
The temperature cable has the slider-type,
self-adjust feature. As the temperature lever of the
control head is cycled through its full range of travel,
the cable clip will assume a position assuring that the
temperature valve will seat in both extreme positions.
The vent and/or defrost cables also have the

1A-2 HEATING AND VENTILATION
520003-1 A
Fig. 3 Interior Body Air & Exit - Typical Sedan, Station Wagon
self-adjusting feature. Blower speeds are controllable in
all modes (VENT, HEAT, DEFROST) by the switch
on the control head.
The power-vent ventilation feature is available in
the vent mode. Outside air enters the plenum and is
driven by the blower to the temperature valve. In the
cold position of the temperature valve, air bypasses the
heater core to the vent valve opening and enters the
passenger compartment through the vent duct and
outlets
in the center of the instrument panel. If some
heated air is desired, the temperature valve may be
opened. This allows mixed (tempered) air to flow out
the center vent opening. Blending air between modes
can be done by varying the mode selector.
Varying the selector between "Heat" and
"Defrost" will allow more air or less air to be directed
out either the defroster outlet or the heater outlet. The
closer the mode selector is positioned to the "Heater"
position, the larger the amount of air coming out the
heater outlet. The closer the mode selector is
positioned to "Defrost," the larger the amount of air
going to the windshield. The temperature of this air is
governed by the temperature lever position. Side window
defogging, if so equipped, is
provided via ducts in the outboard corners of the
instrument panel. Maximum air flow from these vents
will be in "Heater" mode with reduced air flow in
"Defrost" mode.
Varying the mode selector between "Heater" and
"Vent" positions varies the proportion of air coming
out the heater outlet and the center vent outlets. With
the selector in some midway position, air coming out
the center vent outlets will be ambient temperature,
while air out the heater outlet will be mixed warm air,
its temperature depending on temperature lever
position.
In the heat and defrost mode, outside air is driven by
the blower to the temperature valve which, depending
upon its position as controlled by the operator, distributes
all or some portion of the inlet air through the heater core.
The vent valve will prevent air entry into the vent duct and
direct this ambient air to the mix portion of the heater
module. The air is thus heated, mixed, and then directed
into either the defroster duct or the heater outlet by the
position of the mode valve and control lever.
A small
amount of air is bled to the side window defogger system.

HEAPING AND VENTILA"T0N 1A-3
1, LEFT AND RIGHT SIDE WINDOW 3. POWER VENTIHEAT 5. LEFT AND RIGHT RAM AIR
DEFOG OUTLETS* OUTLETS VENT OUTLETS*
2. LEFT AND RIGHT DEFROSTER 4. RAM AIR VENT
OUTLETS CONTROLS* * NOT ON ALL MODELS J10001-1A-F
Fig. 4 Heater Ventilation System - Typical
1-THIS POSITION ALLOWS OUTSIDE AIR FLOW 3-THIS
POSITION ALLOWS ABOUT 80% AIR
TO FLOOR OUTLET. (ADDITIONAL VENTED FLOW
TO WINDSHIELD AND 20% TO FLOOR.
AIR CAN BE DISTRIBUTED INSIDE CAR BY
OPERATING VENT KNOBS.) 4-TEMPERATURE
LEVER POSITION WILL
REGULATE OUTLET AIR TEMPERATURE BY
2-POSITION OF
THIS SYSTEM SELECTOR BLENDING
THE INCOMING OUTSIDE AIR
LEVER DETERMINES AIR FLOW FROM THROUGHIAROUND THE HEATER CORE.
FLOOR, INSTRUMENT PANEL OR WIND-
SHIELD OUTLET - IN "HEATER", FLOW IS 5-THE
FAN CONTROL LEVER (OFF - HI) PRO.
ABOUT
80% TO FLOOR AND 20% TO WIND- VIBES SPEED CONTROL OF THE FAN.
SHIELD OUTLETS (AND
SlDE WINDOW DE-
FOGGERS).
Fig. 5 Heater Control - Typical

1A-4 HEATING AND VENTILATION
1-DEFROSTER OUTLET
7-PURGE DOOR OPENS TO ALLOW
11-AIR DOOR CLOSES OFF HEATER
AIR FLOW INTO CAR UNDER I.P.
AND DEFROSTER OUTLETS WHEN
2-BLENDED AIR WHEN SYSTEM SELECTOR LEVER SYSTEM SELECTOR LEVER IS
IS MOVED TO "OFF"
MOVED TO "OFF"
3-HEATER CORE
8-UNTEMPERED AIR
12-DEFROSTER DOOR MOVES BY
4-BLOWER OPERATION OF HEATER
9-WARMED AIR CONTROLS SYSTEM SELECTOR
5-DASH PANEL LEVER
10-TEMPERATURE DOOR MOVES BY
6-OUTSIDE AIR FROM COWL
OPERATION OF TEMPERATURE "ON
SOME MODELS ALSO
PLENUM CHAMBER
LEVER ON HEATER CONTROL SUPPLIES
SIDE WINDOW
DEFOGGING DUCTS.
. -.
Fig. 6 Typical Heater System Air Flow

HEATING AND VENTILATION 1A-5
@ INSUFFICIENT HEATING OR DEFROST lNG
OF THE HEATER
IF PROBLEM
NOT RESOLVED THEN
HECK FOR AIRFLOW OUT DEFROSTER
VENT OUTLETS
INSTALL THE RADIATOR CAP. WITH ENGINE WARM,
DRIVE THE VEHICLE AT
48 KPH(3OMPH). WITH A THER-
MOMETER, CHECK THE AMBIENT AIR TEMPERATURE
CONTINUED AT TOP OF NEXT PAGE
Fig. 7 Insufficient Heating or Defrosting Diagnosis Procedure (7 of 2)

1A-6 HEATING AND VENTILATION
CHECK VEHICLE FOR
COLD AIR LEAKS AT DASH,
HEATER CASES AND FROM
VENTS. CHECK
UNDERSEAT FOR
OBSTRUCTIONS.
w
TEN FOR DOOR SLAM PRIOR TO THE END
CHECK THE TEMPERA-
TURE DOOR ADJUSTMENT,
CABLES, LINKAGE AND AD-
JUST TO FULL HOT. CHECK
I
WITH THE TEMPERATURE
DOOR FULL HOT, START THE
VEHICLE. CHECK THE TEMPER- ATURE OF THE HEATER INLET
AND OUTLET HOSES BY FEEL.
THE AIR TEMPERATURE
AROUND THE HOSES MUST BE AT LEAST
85OF.
I
WITH THE BLOWER ON
HIGH, MOVE THE TEMP-
ERATURE LEVER FROM
FULL HOT TO FULL
COLD AND LISTEN FOR
AIRFLOW CHANGE.
CHECK THE TEMPER-
ATURE DOOR AD-
JUSTMENT, CABLES,
CONTROL, LINKAGE
&
BETWEEN THE
COOLANT REPLACE.
Fig. 8 Insufficient Heating or Defrosting Diagnosis Procedure (2 of 2)

HEATING AND VENTILATION 1A-7
@ BLOWER ELECTRICAL
LOCATE SHORT IN THE
FOLLOWING WIRES:
1. FROM THE FUSE PANEL
2. FROM THE BLOWER
SPEED SWITCH TO THE
HEATER RESISTOR BLOCK.
3. FROM THE HEATER RE-
SISTOR BLOCK. CONNECT A
JUMPER LEAD FROM THE BAT-
TERY POSITIVE TERMINAL TO
ANY
WlRE TERMINAL IN THE
CONNECTOR. USE
12 VOLT
TEST LIGHT TO CHECK FOR
VOLTAGE AT THE CORRES-
PONDING WIRE ON THE
USE THE
12 VOLT
TEST LIGHT TO
CHECK THE POWER
FEED TERMINAL ON
THE BLOWER
SPEED SWITCH
TEST LAMP DOES BLOWER
SPEED SWITCH.
REPAIR OPEN IN FEED
WlRE FROM RESISTOR TO
BLOWER MOTOR.
Fig. 9 Blower Electrical Diagnosis