
1988 
SER 
This manual  applies to the  1988  Pontiac Firebird Models. 
It contains  the latest  product information  available at the 
time  of  publication  approval. lnformation  pertaining to 
the operation  of the  vehicle  is contained  in the  Owner's 
Manual  which accompanies  each vehicle.  The right  is 
reserved  to make changes  at any  time  without  notice. 
Any  references  to brand  names  in this manual  is intended 
merely  as an  example  of the  types  of 
lubricant% tools, 
materials, etc, recommended  for use  in servicing  1988 
Pontiac  Models. In all  cases, an equivalent  may be used. 
PONTIAC DIVISION 
GENERAL 
MOTORS CORPORATION 
PONTIAC,  MICHIGAN 48053 
1987 General  Motors Corp. All Rights  Reserved. 
No  part  of  this publication  may be reproduced,  stored in any 
retrieval  system  or transmitted  in any  form  or by  any  means, 
including  but  not  limited  to electronic,  mechanical, 
photocopying,  recording or otherwise,  without the prior written 
permission  of General  Motors Corp. This  includes  all  text, 
illustrations, tables  and charts. 
S-881  OF  9-87 Printed in Canada 
TABLE  OF CONTENTS 
SECTION  NAME 
GENERAL  INFORMATION 
OA. General  lnformation 
OB.  Maintenance & Lubrication 
1 SECT. 
HEATING  AND AIR CONDITIONING 
1A. Heating  and Ventilation 
1  B.  Air  Conditioning 
1D1. R-4 AIC Com~ressor Overhaul 
FRAME  AND BUMPERS 
2B.  Bumpers 2C. Chassis  Sheet Metal 
STEERING,  SUSPENSION,  WHEELS 
AND  TIRES 
3.  Diagnosis 
3A.  Wheel  Alignment 
3B5. Steering Wheels and Columns 3B6. Steering  Linkage 3B7. Power Steering  Gear and Pump 
3C.  Front Suspension 
3D.  Rear Suspension 
3E.  Tires  and Wheels 
FINAL  DRIVE 
4A.  Propeller  Shaft 
4B.  Rear  Axle 
4B1. Bora-Warner Axle 
BRAKES 5. Brakes 5A3. Comoosite Master Cvlinder 5B1. Disc  r rake Caliper ~ssembly - 300013100  Series 5B6. Disc Brake  Caliper  Assembly - 3548 
Series 
5C3. Direct  Torque  Drum Brake Assembly 5D2. Power  Head Assembly - Tandem Diaohraam 5F. ~~ecifications and Special  Tools 
ENGINE 6. Engine  General lnformation 6A2. 2.8L 6A3. 5.OL & 5.7L 6B. Engine Cooling 
6C. En~ine Fuel 
6D. ~ngine Electrical 6D1. Battery 6D2. Cranking  System 6D3. Charging System 6D4. Ignition System 6D5. Engine Wiring 
6E.  Driveabilitv  and Emissions 
6E2. ~missions' 6E3. Emissions - PFI 
6F.  Engine  Exhaust 
TRANSMISSION 7A. Automatic  Transmission - General 
lnformation 
7A1. Automatic  Transmission - On-Car 
Service 
700R4. Automatic  Transmission  Hydraulic Diagnosis 
700R4. Automatic  Transmission Unit  Repair 
76. 5-Speed  Manual Transmission 
7C.  Clutch 
CHASSIS  ELECTRICAL 8A. Electrical  Diagnosis 
8B.  Lighting  and Horns 
8C.  Instrument 
Panel, Gages 
& Console 
8E.  Windshield  Wiper  &Washer System 
ACCESSORIES 9A. Radio Systems  and Antennas 9B. Cruise Control 9G. Miscellaneous  Accessories 
I BODY SERVICE  MANUAL  END 
OF 
MANUAL   

GENERAL INFORMATION OA-1 
SECTION (DA 
GENERAL NFORMAT 
CONTENTS 
................................... General Description OA- 1 Prevailing Torque  Fasteners ......................... OA-2 
...................................... Body Number  Plate OA- 1 Recommendations  For Fastener  Reuse ........ OA-2 
..................... Vehicle Identification  Number OA- 1 Vehicle Lifting  Procedures ............ ., ............. OA-2 
......................................... Metric Fasteners OA- 1 Precautions Against Tipping ........................ OA-7 
................... Fastener  Strength  Identification OA-2 Automotive Abbreviations ................... .... 0.4- 1 1 
GENERAL DESCRIPTION 
Only general information  appears in this  section.  left 
of the  windshield,  see Figure 2. Refer  to Figure 3 
Detailed  specifications  on major  units are given  at the  for  detailed  "VIN"  code information. 
For Engine V.I. 
end  of each  respective section  of this  manual.  N.  Location, refer to Figure 
4. 
BODY NUMBER PLATE METRIC FASTENERS 
The  Body  Number  Plate  (Fig. 1) is attached  to 
Pontiac models are primarily  dimensioned in  the 
the  front  tie bar  behind  either the right  or left 
headlamp metric system, Most fasteners are metric and are very in the engine On The close in dimension to well-known customary fasteners Number Plate  identifies numerous  items as outlined  in in the inch system. It is most important that Figure 1. re~lacement fasteners  be of the  correct  nominal 
VEHICLE  IDENTIFICATION  NUMBER d&meter, thread  pitch  and  strength. 
Original  equipment  metric fasteners  (except 
The  Vehicle Identification  Number (VIN) Plate  "beauty"  bolts,  such 
as exposed  bumper bolts, and 
is  located  on top  of the  instrument  panel at the  lower  cross 
recess  head  screws)  are identified  by a number 
1 -- BODY  STYLE 
2 ASSEMBLY PUNT 
3 -- UNIT NUMBER 
4 -- PAINT  TYPE 
5 - ROOF OPTION 
6 -- SEAT OPTION 
7 - TRIM COMBINATION 
8 - UPPER  BODY 
9 - UPPER COLOR 
10 -- LOWER  BODY 
11 - REMAINING  LINES 
- AVAILABLE FOR 
--PLANT 
USE 
12 - LOWER COLOR 
13 - MODEL  YEAR 
14 -- TIME BUILD CODE 
15 - DIVISION 
16 - BODY TvPE 
6200224A 
Fig. 1 Body Number Plate   

- - 
GENERAL INFORMATION  OA-13 
LIST OF AUTOMOTIVE  ABBREVIATIONS 
WHICH  MAY 
BE USED IN THIS  MANUAL 
A-6 - Axial 6 Cyl. A  C Compressor AIC - Air Conditioning 
ACC - Auto'matic Climate  Control 
EMF 
- Electromotive Force PAIR - Pulse Air Injection  Reaction System 
EMR - Electronic  Module Retard 
P B - Power  Brakes 
EOS - Exhaust  Oxygen  Sensor 
PCV - Positive Crankcase  Ventilation 
ESC - Electronic  Spark  Control 
PECV - Power Enrichment  Control Valve 
APT 
- Adjustable  Part Throttle 
AT - Automatic  Transmission 
ATC - Automatic  Temperature  Control 
ATDC 
- After  Top Dead  Center 
FMVSS 
- Federal  Motor Vehicle  Safety BAR0 - Barometric  Absolute  Pressure  Sensor 
Ft. Lb. - Foot  Pounds (Torque) 
Bat. + - Positive  Terminal  FWD - Front Wheel  Drive 
- Four Wheel  Drive 
BHP - Brake  Horsepower  4 x 4 - Four Wheel  Drive 
BP - Back  Pressure 
BTDC - Before  Top Dead  Center 
HD - Heavy Duty HE1 - High Energy  Ignition 
Cat.  Conv. - Catalytic  Converter 
CC - Catalytic  Converter 
- Cubic  Centimeter - Converter  Clutch 
CCC - Computer  Command  Control 
HVM 
- Heater-Vent-Module 
IAC 
- ldle  Air Control CCOT - Cycling  Clutch  (Orifice) Tube IC - Integrated  Circuit CCP - Controlled  Canister  Purge 
ID - Identification 
C.E. - Check  Engine - Inside Diameter 
CEAB - Cold  Engine Airbleed ILC - Idle Load  Compensator 
CEMF - Counter  Electromotive  Force I/P - Instrument Panel 
CID - Cubic Inch Displacement  ISC - Idle Speed Control CLOOp - Closed  Loop 
CLCC - Closed  Loop Carburetor  Control  km - Kilometers 
CP 
- Canister  Purge kmiL - Kilometers  Liter  (mpg) Cu. In. - Cubic Inch kPa - Kilopascals 
CV - Constant  Velocity 
Cyl. 
- Cylinder(s) 
L-4 - Four  Cylinder  In-Line (Engine) 
DBB - Dual  Bed Bead L-6 - Six Cylinder  In-Line (Engine) 
DBM - Dual  Bed  Monolith 
LF - Left  Front DEFl - Digital Electronic  Fuel  Injection LR - Left Rear DFI - Digital  Fuel Injection 
Diff. - Differential  Man. Vac. - Manifold Vacuum Distr. - Distributor  MAP - Manifold Absolute Pressure 
EAC 
- Electric  Air Control Valve 
EAS - Electric  Air Switching  Valve  MPG - Miles Per Gallon 
ECC - Electronic  Comfort Control 
MPH - Miles Per Hour 
ECM - Electronic  Control Module  MT - Manual Transmission 
N.m - Newton Metres (Torque) 
Emission  Control 
Fig. 014-15 -- Common Abbreviations   

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.   

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-10 HEATING AND VENTILATION 
@ CONTROLS 
CHECK  CABLES  FOR ROUTING, KINKEC CABLES, 
WIRING INTERFERENCE  OR OTHER  INSTRUMENT 
PANEL  INTERFERENCE. 
REMOVE CABLE  FROM 
DOOR(S) 
CAUSING  BINDING 
AND  CYCLE 
DOOR(§) 
MANUALLY.  CHECK 
FOR DOOR  BINDING  MOVES 
ON 
HIGH BLOWER 
WlTH A LONGER  CABLE AND 
ADD  A LOOP  TO THE CABLE 
ROUTING  TO INCREASE CONTROL 
EFFORT,  CHECK  INSTRUMENT 
PANEL INTERFERENCES 
WlTH 
NEW  CABLE ROUTING  TO INSURE 
PROPER 
OPERATI 
INSTALLATION 
I 
SEAL  OK 
SHAFT  ALIGNMENT,  BENT 
Fig. 12 Heater Controls Diagnosis