1988 PONTIAC FIERO spark plugs

F CARLINE
ITEM 10
TransmissionRransaxle Service
The manual transmission or transaxle fluid does not
require changing. (Corvette only.) Change fluid in over-
drive unit every 30,000 miles (50 000 km).
For automatic transmissions or transaxles, change
both the fluid and filter every 15,000 miles (25 000 km) if
the car is mainly driven under one or more of these
conditions:
@ In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
@ In hilly or mountainous terrain.
@ Frequent trailer pulling.
@ Uses such as found in taxi, police car or delivery
service.
If you do not use your car under any of these condi-
tions, change both the fluid and filter every 100,000 miles
(160 000 km). See you Owner's Manual for further
details.
ITEM 11
Spark Plug Service*
Replace spark plugs with type listed in your Owner's
Manual.
ITEM 12
Spark Plug Wire Inspection*
Clean wires and inspect for burns, cracks or other dam-
age. Check the wire boot fit at distributor and at spark plugs.
Replace wires as needed.
ITEM 13
Positive Crankcase Ventilation (PCV) Valve
Inspection*
Inspect valve for proper function. Replace valve if
necessary as well as any worn, plugged or collapsed
hoses.
ITEM 14
EGR System Service*
Conduct EGR System Service as referenced in the
EGR System Chart shown in the appropriate 6E Section.
Also, refer to your GM maintenance schedule booklet for
specific applications.
ITEM 15
Air Cleaner and PCV Filter Replacement*
On 1.6 and 2.0 liter engines, replace every 50,000
miles (80 000 km). On all other engines, replace every
30,000 miles (50 000 km). Replace more often under
dusty conditions. Ask your dealer for the proper replace-
ment interval for your driving conditions.
MAINTENANCE AND LUBRICATION 08-3
ITEM 16
Engine Timing Check*
Adjust timing to underhood label specifications. If
no specifications are shown, no adjustment is needed.
ITEM 17
Fuel Tank, Cap and Lines Inspection*
Inspect fuel tank, cap and lines (including fuel rails
and injection assembly, if so equipped) for damage or
leaks. Inspect fuel cap gasket for an even filler neck
imprint or any damage. Replace parts as needed.
ITEM 18
Thermostatically Controlled Air Cleaner
Inspection*
If your car is equipped, inspect all hoses and ducts
for proper hookup. Make sure valve works properly.
OWNER INSPECTIONS AND SERVICES
Listed below are inspections and services which
should be made by either you or a qualified technician at
the intervals shown to help ensure proper safety, emission
performance and dependability of your car. Take any
problems promptly to your dealer or another qualified
technician for service advice. Whenever repairs are neces-
sary, have them completed at once. For your safety and
that of others, any safety-related parts that could have
been damaged in an accident should be inspected and all
needed repairs should be done before operating your car.
Be sure to use the proper fluids and lubricants as shown in
Figure OB-2.
WHILE OPERATING YOUR VEHICLE
Automatic transmissionltransaxle shift indi-
cator operation - Make sure the indicator points to the
gear chosen.
Horn operation - Blow the horn occasionally to
make sure it works. Check all button locations.
I
Brake system operation -- Be alert to abnormal
sounds, increased brake pedal travel or repeated pulling to
one side when braking. Also, if a brake warning light
comes on or flashes, or the anti-lock warning light (if
equipped) comes on or remains on, something may be
wrong with part of the brake system. Have it inspected and
repaired at once.
Exhaust system operation - Be alert to any
changes in the sound of the system or any smell of fumes.
These are signs the system may be leaking or overheating.
.
Have it inspected and repaired at once. Also see "Engine
Exhaust Gas Caution (Carbon Monoxide)" and "Catalytic
Converter" in your Owner's Manual.
*An Emission Control Service

ENGINE GENERAL INFORMATION 6-1
SECTION 6
NE GENERAL NFORMAT
Description ............................................................... 6 TBI ...................................... .. ...... 6E2 ................ Engine Mechanical Multi Port Fuel Injection (MPFI) 6E3 -
............................................... 2.8L V-6 ....................................................... 6A2 Exhaust Systems 6F
5.OL V-8 ......................................................... 6A3 ~~~~~~l ~~f~~~~ti~~ ..................................... 6-2
............................ Engine Cooling ...................................................... 6B Engine Performance Diagnosis 6-3 ............................. Engine Fuel 6C Engine Mechanical Diagnosis
6-3 ........................................................... ................................... Engine Knock Diagnosis 6-4
Engine Electrical ................................................... 6D Compression Test ...................................... ... 6-5
................... Driveability and Emission Controls ...................... 6E Oil Leak Detection .. ..................... 6-5
ALL NEW GENERAL MOTORS VEHICLES ARE CERTIFIED BY THE UNITED STATES
ENVIRONMENTAL PROTECTION AGENCY AS CONFORMING TO THE REQUIREMENTS OF
THE REGULATIONS FOR THE CONTROL OF AIR POLLUTION FROM NEW MOTOR VEHICLES.
THlS CERTIFICATION IS CONTINGENT ON CERTAIN ADJUSTMENTS BEING SET TO
FACTORY STANDARDS. IN MOST CASES, THESE ADJUSTMENT POINTS EITHER HAVE
BEEN PERMANENTLY SEALED AND/OR MADE INACCESSIBLE TO PREVENT
INDISCRIMINATE OR ROUTINE ADJUSTMENT IN THE FIELD. FOR
THlS REASON, THE
FACTORY PROCEDURE FOR TEMPORARILY REMOVING PLUGS, CAPS, ETC., FOR
PURPOSES OF SERVICING THE PRODUCT MUST BE STRICTLY FOLLOWED AND,
WHEREVER PRACTICABLE, RETURNED TO THE ORIGINAL INTENT OF THE DESIGN.
DESCRIPTION OF: SECTION 6
SECTION 6A - ENGINE MECHANICAL used for each carburetor. TBI units are described in
This section general contains information on the Section 6E.
mechanical parts of the engine, such as block,
crankshaft, pistons, valve train, and camshaft, that are
common to most engines. Overhaul procedures,
removal and replacement procedures, and
s~ecifications are also covered. Subsections furnish
detailed information on each specific engine. Service
SECTION 6D - ENG l N E ELECTRICAL
information is also given that relates to that engine's
use in each
Carline. Specific subsections are: Items
covered in this section are battery,
generator, starter, primary and secondary ignition,
6A2
- 2.8L V-6 Engine
engine wire harness, spark plugs and wires, and
6A3
- 5.OL V-8 Engine
ignition switch.
SECTION 6B - ENGINE COOLING
Engine cooling system components such as
radiator, water pump, thermostat, and cooling fan, are
covered in this section. Accessory drive belts are also
covered, along with cooling system capacities.
SECTION 6C - FUEL SYSTEM
This section contains information on all the parts
of the fuel system
except the carburetor, or Throttle
Body Injection unit (TBI) itself. Items covered are fuel
tank, fuel pump, and fuel lines. Specific subsections are
SECTION 6E - DRIVEABILITY AND EMISSIONS
This section covers emission control systems
general information, and diagnostic procedures which
will lead to repairing performance and driveability
related problems for gasoline engine equipped vehicles.
All emission components are covered, as well as all
removal and replacement procedures. Instructions on
use of special tools are also given. Specific sections are:
6E
- Driveability and Emissions
6E2
- Fuel Injection (TBI)

6-2 ENGINE GENERAL INFORMATION
6E3 - Fuel Injection (Ported) This section has information
on all exhaust
system parts, such as tailpipes, mufflers, and the
SECTION 6F - EXHAUST SYSTEM catalytic converter.
GENERAL INFORMAflION
CLEANLINESS AND CARE
An automobile engine is a combination of many
machined, honed, polished and lapped surfaces with
tolerances that are measured in the ten-thousandths of
an inch. When any internal engine parts are serviced,
care and cleanliness are important. A liberal coating of
engine oil should be applied to friction areas during
assembly, to protect and lubricate the surfaces on
initial operation. Throughout this section, it should be
understood that proper cleaning and protection of
machined surfaces and friction areas is part of the
repair procedure. This is considered standard shop
practice, even if not specifically stated. PREVENTING
DAMAGE AND IN
CONTRIBUTING TO RELIABLE ENGINE
PERFORMANCE.
When raising or supporting the engine for any
reason, do not use a jack under the oil pan. Due to the
small clearance between the oil pan and the oil pump
screen, jacking against the oil pan may cause it to be
bent against the pump screen resulting in a damaged
oil pick-up unit.
When working on the engine, remember that the
12-volt electrical system is capable of causing short
circuits. When performing any work where electrical terminals could possibly be grounded, the ground cable
of the battery should be disconnected at the battery.
Any time the carburetor or air cleaner is
train components are removed removed, the intake opening should be covered. This for service, they should be in order' will protect against entrance of foreign be installed in the same locations, and with the same material, which could follow the intake passage into mating surfaces, as when removed
the cylinder and cause extensive damage when the -
Battery cables should be disconnected before any engin; is started.
major work is performed on the engine. Failure to IN THE MECHANICAL PROCEDURES
disconnect cables may result in damage to wire harness DESCRIBED IN THIS SECTION, GENERALLY
or other electrical parts. NO
REFERENCES WILL BE MADE TO THE
REMOVAL OF OPTIONAL EQUIPMENT SUCH
ENGINE SERVICE AS POWER STEERING PUMP, AIR
CONDITIONING COMPRESSOR, ETC.
THE FOLLOWING INFORMATION ON SHOULD IT BECOME NECESSARY TO
ENGINE SERVICE SHOULD BE NOTED REMOVE ANY SUCH ITEM TO
PERFORM
CAREFULLY, AS IT IS IMPORTANT IN OTHER SERVICE, REFER TO THE
APPROPRIATE SECTION OF THIS SERVICE
MANUAL FOR SPECIFIC INFORMATION.
ENGINE PERFORMANCE DIAGNOSIS
INTRODUCTION interchangeably for so long, it was necessary to decide
on the most common usage and then define them. If the
Engine Performance procedures are definition is not understood, and the exact Symptom is
guides that will lead to the most probable causes of not used, the Diagnostic procedure will not work. engine performance complaints. They cover the
components of the fuel, ignition, and mechanical It
is important to keep two facts in mind:
systems that could cause a particular
complaint, and 1. The procedures are written to diagnose problems
then outline repairs in a logical sequence. on cars
that have
"run well at one time" and
that time and wear have created the condition.
It is important to determine if the
"Service ~~~i~~ soon- light is "ON,~' or has come for 2. All possible causes cannot be covered,
a short interval while driving. If the
"Service Engine particularly with regard to emission controls. If
Soon" light has come "ON," the Computer doing the work prescribed does not correct the
Command Control System or DECS should be complaint, then either the wrong Symptom was
checked for stored
"Trouble Codes" (See Diagnostic used, or a more detailed analysis will have to be
Circuit Check, Section 6E, for the engine you are made.
working on) which may indicate the cause for the All of the Symptoms can be caused by worn out
performance
complaint.Each Symptom is defined, and or defective parts such as Spark Plugs, Ignition
it is important that the correct one be selected, based Wiring, etc. If time and/or mileage indicate that
on the complaints reported or found. The definition of parts should be replaced, it is recommended that
each symptom is included with the symptom. it
be done.
The words used may not be what you are used to Refer to:
in all cases, but because these terms have been used
@ Section 6E - Driveability and Emissions

ENGINE GENERAL INFORMATION 6-5
INSTRUMENT PANEL OIL WARNING LAMP "ON" AT IDLE
1. Oil cooler, or oil or cooler line restricted. Remove 2. Oil pump pressure low. See oil pump repair
restrictions in cooler or cooler line. procedures
in Section
6A.
ENGINE COMPRESSION EST
COMPRESSION TEST
Important
e Disconnect the "BAT." terminal from the - HE1 distributor or ignition module.
To determine if the valves or pistons are at fault,
a test should be made to determine the cylinder
compression pressure. When checking cylinder
compression, the throttle and choke should be open, all
spark plugs removed, and the battery at or near full
charge. The lowest reading cylinder should not be less
than
70% of the highest and no cylinder reading
should be less than
689 kPa (100 PSI). This
should be done with four
"puffs" per
cylinder.
Normal - Compression builds up quickly and
evenly to specified compression on each cylinder.
Piston Rings - Compression low on first
stroke, tends to build up on following strokes, but does
not reach normal. Improves considerably with addition
of oil.
Valves - Low on first stroke, does not tend to
build up on following strokes. Does not improve much
with addition of oil.
Use approximately three squirts from a plunger
type oiler.

2.8 LITER V-6 6A2-9
INTAKE MANIFOLD (FIGURE 6A2-7)
Removal
Disconnect battery.
Remove air cleaner.
Drain coolant.
Refer to Section 6E3 for removal of the following
PFI sub-assemblies.
e Plenum
e Fuel Rail
e Runner
Disconnect spark plug wires at spark plugs.
Disconnect wires at coil.
Remove distributor cap and spark plug wires.
Mark distributor position and remove hold down
bracket.
Remove distributor.
Remove air management hose, manual
transmission only.
Disconnect emission canister hoses. Remove pipe
bracket (front left valve cover).
Remove left valve cover.
Remove air management bracket, manual
transmission only.
Remove right valve cover.
Remove upper radiator hose.
Disconnect heater hose.
Disconnect coolant switches.
Remove manifold bolts.
Remove manifold. Discard manifold gaskets and
remove loose RTV from front and rear ridges of
cylinder case.
Installation
When installing intake gaskets, notice that the
gaskets are marked Right Side and Left Side
(carbureted only). Use them only as indicated to
maintain designed efficiency of this engine.
1. Make
sure that no oil or water is present on
surface when new RTV is applied. Place a 5mm
diameter
(3/16") bead of RTV, # 1052917 or
equivalent, on each ridge.
2. Install
new intake gaskets on cylinder heads.
Hold in place by extending ridge RTV bead up
6mm onto the gasket ends. The new intake
gaskets will have to be cut, where indicated, to
install behind push rods. Cut only those areas
that are necessary.
3. Install intake
manifold on engine. Make sure
areas between case ridges and intake are
completely sealed.
4. Install manifold retaining bolts and nuts and
torque in the sequence shown in Figure 6A2-7.
5. Install heater and radiator hose to manifold.
6. Install rocker covers as previously outlined.
7. Connect coolant switches.
8. Install air management bracket.
9. Install pipe bracket (front left rocker cover).
10. Install distributor, distributor cap and retaining
nut. Do not tighten.
11. Refer to Section 6E3 for installation of PFI
sub-assemblies removed. 12.
Connect
necessary wires and hoses.
13. Fill cooling system with
the proper mixture of
ethylene glycol anti-freeze and water. Do not
install radiator cap.
14. Start
engine, set intitial timing. After set, torque
distibutor hold down clamp bolt to 34
N-m (25
lb. ft.). Recheck timing after torquing bolt.
15. Let engine
run until radiator upper hose becomes
hot (thermostat open).
16. With
engine idling, add coolant to radiator, if
necessary, until level reaches bottom of filler
neck.
17. Install
radiator cap, making sure arrows on cap
line up with overflow tube.
Figure 6A2-8 Exhaust Manifold
EXHAUST MANIFOLD (FIGURE 6A2-8)
Removal (Left)
1. Disconnect battery.
2. Raise vehicle.
3. Disconnect exhaust pipe.
4. Remove
(4) rear manifold bolts and (1) nut.
5. Lower vehicle.
6. Disconnect air management, hoses and wires.
7. Remove power steering and fuel line bracket.
8. Remove manifold.
Installation (Left)
1. Clean mating surfaces on manifold and head,
then install manifold in position and install bolts.
2. Torque
manifold bolts to 34
N.m (25 ft. lbs.).
3. Install power steering bracket.
4. Raise vehicle.
5. Install exhaust pipe.
6. Lower vehicle.
7. Connect battery.
Removal (Right)
1. Disconnect battery.
2. Raise vehicle.
3. Disconnect exhaust pipe.
4. Lower vehicle.

4. Remove bearing cap. The flattened gaging plastic
will be found adhering to either the bearing shell
or journal.
5. On the edge of gaging plastic envelope, there is a
graduated scale which is correlated in
thousandths of a millimetre. Without removing
the gaging plastic, measure its compressed width
(at the widest point) with the graduations on the
gaging plastic envelope. Normally, main bearing
journals wear evenly and are not out-of-round.
However, if
a bearing is being fitted to an
out-of-round (.025mm max.), be sure to fit to the
maximum diameter of the journal: If the bearing
is fitted to the minimum diameter and the journal
is out-of-round
.025mm, interference between the
bearing and journal will result in rapid bearing
failure. If the flattened gaging plastic tapers
toward the middle or ends, there is a difference
in clearance indicating taper, low spot or other
irregularity of the bearing or journal. Be sure to
measure the journal with a micrometer if the
flattened gaging plastic indicates more than
,025mm difference.
6. If the bearing clearance is within specifications,
the bearing insert is satisfactory. If the clearance
is not within specifications, replace the insert.
Always replace both upper and lower inserts as
a unit.
7. A standard,
.016mm and .032mm undersize
bearing may produce the proper clearance. If not,
it will be necessary to regrind the crankshaft
journal for use with the next undersize bearing.
After selecting new bearing, recheck clearance.
8. Proceed to the next bearing. After all bearings
have been checked rotate the crankshaft to see
that there is no excessive drag.
9. Measure crankshaft end play (see specifications)
by forcing the crankshaft to the extreme front
position. Measure at the front end of the
#3 main
bearing with a feeler gage (Figure 6A2-25).
10. Install a new rear main bearing oil seal in the
cylinder block and main bearing cap.
Figure 6A2-25 Measuring Crankshaft End Play
Replacement
Main bearings may be replaced with or without
removing the crankshaft.
With Crankshaft Removal
1. Remove and inspect the crankshaft.
2. Remove the main bearings from the cylinder
block and main bearing caps.
3. Coat bearing surfaces of new, correct size, main
bearings with oil and install in the cylinder block
and main bearing caps.
4. Install the crankshaft.
Without Crankshaft Removal
With oil pan, oil pump and spark plugs removed,
remove cap on main bearing requiring
replacement and remove bearing from cap.
Install a main bearing removing and installing
tool in oil hole in crankshaft journal. If such a
tool is not available, a cotter pin may be bent as
required to do the job.
Rotate the crankshaft clockwise as viewed from
the front of engine. This will roll upper bearing
out of block.
Oil new selected size upper bearing and insert
plain (unnotched) end between crankshaft and
indented or notched side of block. Rotate the
bearing into place and remove tool from oil hole
in crankshaft journal. Inspect for burrs at oil hole,
remove if required.
Oil new lower bearing and install in bearing cap.
Install main bearing cap with arrows pointing
toward front of engine.
Torque all main bearing caps, EXCEPT THE
#3 MAIN CAP, to 95 N.m (70 lb. ft.). Torque
# 3 main bearing cap to 15 N m (1 1 lb. ft.) then
tap end of crankshaft, first rearward then forward
with a lead hammer. This will line up rear main
bearing and crankshaft thrust surfaces.
Retorque
all main bearing caps to 95 N.m (70 Ib. ft.).
1 /DUST LIP
Figure 6A2-26 Removing Seal

6A2-26 2.8 LITER V-6
2. Remove the spark plugs. Installation
3. Remove
crankshaft pulley and torsional damper. 1. Install rear main bearing oil seal in cylinder block
4. Remove oil pan and oil pump. and
rear bearing cap grooves.
5. Remove water pump, crankcase front cover, 2. Lubricate seal with engine oil. Keep oil off
camshaft sprocket and timing chain. parting
line surface.
3. Install main bearings in cylinder block and main
6. Check the connecting rod caps for cylinder
bearing caps then lubricate bearing surface with
number identification. If necessary mark them.
engine oil.
7. Remove the connecting rod caps and
push the
4. 1n;tall crankshaft, being careful not to damage
pistons to top of bores.
bearing surfaces.
8. Remove main bearing caps and lift crankshaft out 5. Recheck bearing clearances using plastigage.
of cylinder block. 6.
Apply a thin coat of anaerobic sealant
# 1052357
9. Remove rear
main bearing oil seal and main or
equivalent to rear of the block mating surface
bearings from cylinder block and main bearing or corresponding
surface or rear main cap only.
caps. Do
not allow sealer on crankshaft or seal.
7. Install main bearing caps with arrow pointing
Cleaning and Inspection toward front of engine.
8. Torque all except
#3 main bearing cap bolts to
1. Wash crankshaft in solvent and dry with
specifications. Torque
#3 main bearing cap bolts
compressed air. to 14-16
N-m (10-12 lbs. ft.) then tap end of
2. Measure
dimensions of main bearing journals and crankshaft, first rearward then forward with a
crankpins with a micrometer for out-of-round, lead
hammer. This will line up rear main bearing
taper or undersize (See Specifications). and crankshaft
thrust surfaces.
Retorque all main
3. Check
crankshaft for run-out by supporting at bearing
cap bolts to specifications.
the front and rear main bearings journals in "V" 9. Measure crankshaft
end play with a feeler gage.
blocks and check at the front and rear Force crankshaft forward and measure clearance
intermediate journals with a dial indicator (See between the front of the
#3 main bearing and
Specifications). crankshaft thrust surface.
4. Replace or recondition the crankshaft if out of 10.
Install flywheel and torque to specifications.
specifications.
SPROCKET OR GEAR REPLACEMENT
Remove crankshaft sprocket using Tool J-5825,
install using Tool J-5590.
GENERAL DATA
TYPE .................................................................................................................................... 60" V-6
DISPLACEMENT
............................................................................................................. 2.8 Liter
RPO
........................................................................................................................................... LB8
BORE ......................................................................................................................................... 89
STROKE
................................... .... ............................................................................................... 76
COMPRESSION RATIO
....................................................................................................... 8.9: 1
FIRING ORDER
.......................................................................................................... 1-2-3-4-5-6
Cylinder Bore
DIAMETER .............................................................................................................. 88.992-88.070
OUT OF ROUND
............................................................................................................. .02 Max.
TAPER-THRUST SIDE
................................................................................................. .02 Max.
Piston
CLEARANCE .................................................................................................................. .O 17-,043
Piston Ring

Approx. # of Coils ................................... .... ............................................................................. 4
SPECIFICATIONS
................................................................................ Camshaft Sprocket 20-35 N-m, 15-25
ft. lbs.
................................................................................... Camshaft Rear Cover 8-12 N-m, 6-9 ft. 1bs.
......................................................................... . Connecting Rod Caps 46-60 N m, 34-45
ft. lbs.
............................................................................ Torsional Damper 90-1
15 N-m, 67-85 ft. lbs.
Dist. Hold Down Bolt ..................... ..... ............................................... 27-41 N.m, 20-3 1 ft. lbs.
................................................................................. Exhaust Manifold 25-42 N.m, 19-3 1 ft. lbs.
Water
Pump
M8~1.25~70.0 ........................................................................................ 18-30 N.m, 13-22 ft. lbs.
MlOx1.5x75.0 .......................... .. ........................................................ 27-48 Nem, 20-35 ft. lbs.
Thermostat Housing ........................................................................... 18-24 N-m, 13-18 ft. lbs.
Inlet Manifold Lower
........................................................................... 18-34 N-m, 13-25 ft. lbs.
............................................ ........................ Inlet Manifold Center .. 20-30 N.m (15-22 ft. lbs.) ............................................................................ Timing Chain Damper 18-24
N . m, 14- 19 ft. lbs.
Rocker Arm Nut
........................................................................................ 6-14 N-m, 5-1 1 ft. Ibs.
Rocker Arm Covers
.................................................................................... 8-20 N-m, 7-15 ft. lbs. ........................................................................................ Spark Plugs 9.5-20.3 N-m, 7-15
ft. lbs.
Oil Pan
M8~1.25x14.0 .................................................................................... 20-30 N.m, 15-22 ft. lbs.
M6xlx16.0 ............................................................................................... 8-12 Nem, 6-9 ft. lbs.
................................................................................ Main Bearing Caps 85-
112 N. m, 63-83 ft. lbs.
Oil Pump
............................................................................................. 35-47 Nem, 25-35 ft. lbs.