1988 PONTIAC FIERO sensor

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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

18-4 AIR CONDITIONING
If replacement of the pressure cycling switch is
necessary, it is important to note that this may be done
without removing the refrigerant charge.
A Schrader-
type valve is located in the pressure switch fitting.
During replacement of the pressure switch, a new
oiled O-ring must be installed and the switch assem-
bled to the specified torque of
6- 13 N*m (5- 10 lb. ft.).
Power Steering Gut-OH, or Anticipate
Switch
Engine idle quality on some cars is maintained
by cutting off the compressor (switch normally
closed) when high power steering loads are imposed.
On other cars the switch (normally open) provides a
signal to the ECM to allow engine control systems to
compensate for high-power steering loads.
Wide-Open Tkroale (WOT) Compressor
Cut-Out
Switch
A switch located on the throttle corltrols of some
carburetor equipped cars opens the circuit to the com-
pressor clutch during full throttle acceleration. The
switch activates a relay that controls the compressor
clutch. During full throttle acceleration
on cars
equipped with TBI or
Em, the TPS sends a signal to
the ECM, thereby controlling the compressor clutch.
Air Conditioning Time Delay Relay
This relay on some cars controls the current to
the entire air conditioning system and provides a short
delay of air conditioning operation upon start-up.
Constant Run Relay
Engine idle quality on some cars is maintained
by a "constant run" system (constant run relay) that
eliminates compressor cycling during engine idle for a
predetermined time after the vehicle has come to rest
from road speed.
If the idle period continues for an
extended time, the
A/C system may return to a con-
ventional C.C.O.T. mode for a short time to prevent
system freeze-up. The
A/C control relay and constant
run relays are both controlled by the Electronic Con-
trol Module (ECM) which determines operating con-
ditions by evaluating input from the distributor
(engine speed), vehicle speed sensor, air sensor and
A/C compressor "on" signal.
5-PRESSURE CYCLING 8-EXPANSION TUBE
SWITCH (ORIFICE)
6-DESSICANT BAG O-LIQUID LINE
7-OIL BLEED HOLE
10-PRESSURE RELIEF
VALVE
@ ee LOW PRESSURE LIQUID HIGH PRESSURE LIQUID LOW PRESURE VAPOR HIGH PRESSURE VAPOR
Figure 2 A/C System - Typical

DISC BRAKE CALIPER ASSEMBLY 581-3
a Measure
Clearance between caliper (13) and bracket
(1 8) stops.
If necessary, remove caliper and file ends of
bracket
(18) stops to provide proper
clearance.
5. Inlet fitting (15), if removed, to 45 N-m (33 lb-ft).
6. Wheels and tires, aligning previous marks.
Remove wheel nuts securing rotor to hub.
e Lower car.
e Torque wheel nuts. See Section 3E
WHEELS AND TIRES.
7. Fill master cylinder to proper level with clean
brake fluid.
Bleed caliper if inlet fitting was removed.
Recheck fluid level.
CLEARANCE BEWEEN CALIPER AND
BRACKET STOPS
SHALL BE
0.13-0.30 MM (0.0050.012 IN.) THREE PLACES
13. CALIPER HOUSING
18. BRACKET
Figure 581-5 Caliper to Bracket Clearance
6. INBOARD SHOE B( LlNlNG 7. WEAR SENSOR 8. SHOE RETAINER
SPRING
13. CALIPER HOUSING
6
2. SLEEVE 3. BUSHING 4. BUSHING 5. OUTBOARD SHOE
LlNlNG
* LUBRICATE WITH SILICONE
Figure 58 1-6 Shoe & Lining Assembly
SHOE AND LINING ASSEMBLIES
Remove or Disconnect (Figures 5B1-6 through
581-18)
1. Calipe; as previously described.
2. Outboard shoe and lining
(5).
6, INBOARD SHOE 8. SHOE RETAINER
Figure 581-7 lnboard Shoe & Retainer
6. INBOARD SHOE B( 8. SHOE RETAINER
LINING SPRING
7. WEAR SENSOR 13. CALIPER HOUSING
Figure 581-8 Installing lnboard Shoe and Lining
5. OUTBOARD SHOE & LINING
13. CALIPER HOUSING
Figure 581-9 Installing Outboard Shoe & Lining
Install or Connect (Figures 581.6 through 581.10)
1. Lubricated new bushings (3 and 4) in grooves in
mounting bolt holes.
3. Inboard shoe and lining (6). 2. Lubricated sleeves (2) in mounting bolts holes.
4. Bushings (3 and 4) from grooves in mounting bolt
holes.
3. Retainer spring (8) on inboard shoe (6).

5814 DISC BRAKE CALIPER ASSEMBLY .
4. Inboard shoe and lining (6) by snapping retainer
spring (8) into piston (1) ID. Wear sensor (7)
should be at the leading edge of shoe during
forward wheel rotation. Shoe must lay flat against
piston.
5. Outboard
shoe and lining (5). Back of shoe must
lay flat against caliper.
6. Caliper as previously described.
7. Apply approximately
778
N (175 lb) force three
times to brake pedal to seat linings.
8. Position 12-inch channel lock pliers (19) over
brake shoe ears and bottom edge of caliper (13).
While holding moderate force (50 Ibs) on brake
pedal, clinch outboard shoe ears to caliper.
19. CHANNEL LOCK
PLIERS
Figure 58 1-1 0 Clinching Procedure
9. BOOT 10. PISTON 11. PISTON SEAL 12. BLEEDER VALVE 13. CALIPER HOUSING 20. SEAL GROOVE HMO01 1-5B1-BF
Figure 581-1 1 Caliper Assembly
UNIT REPAIR
CALIPER OVERHAUL
Tool Required:
J 26267 Boot Seal Installer (64 mm)
J 22904 Boot Seal Installer (74 mm)
J 28735 Boot Seal Installer (80 mm)
I
13. CALlP-ER HOUSING
I
Figure 58 1-1 2 Removing Piston
Disassemble (Figures 581-1 1 through 5B1-13)
1. Caliper completely from vehicle as previously
described.
2. Piston (10) using compressed air into the caliper
inlet hole.
CAUTION: Do not place fingers in
front of the piston in an attempt to
catch or protect it when applying
comrpessed air. This could result in
serious injury.
Important
e Use clean shop towels to pad the interior of
the caliper (13) during removal.
@ Piston (10) for:
e Scoring
Nicks
e Corrosion
e Worn or damaged chrome plating
e Replace piston if any of the above are found.
3. Boot (9), being careful not to scratch housing
bore,
4. Piston seal
(1 1) from groove (20) in caliper (13)
bore with a small wood or plastic tool. Do not use
a metal tool since this may damage caliper bore
or seal groove.
Inspect
@ Caliper bore and seal groove for:
e Scoring
e Nicks
e Corrosion
Wear
e Use crocus cloth to polish out light
corrosion.
@ Replace caliper housing if corrosion in and
around seal groove will not clean up with
crocus cloth.

DISC BRAKE CALIPER ASSEMBLY 586-1
SEC"619RI 5B6
SC BRAKE CAL PER ASSEMBLY
3548 SERIES
CONTENTS
General Description ................................. 5B6-2 Unit Repair ........................................... 5B6-5
On-Car Service ........................................ 5B6-2 Caliper Overhaul ....................................... 5B6-5
Caliper Assembly ....................................... 5B6-2
Parking Brake Adjustment ......................... 5B6-3
Shoe and Lining Assembly ......................... 5B6-4
22 LEVER SEAL
1. NUT
2. LEVER
3. RETURN SPRING 4. BOLT 5. BRACKET 8.
BOLT 15.
BALANCE SPRING
23. MOUNT~NG BOLT 9. COPPER WASHER 16. ACUTATOR SCREW 24. BOOT
10 FITTING 17.
PISTON SEAL 25. INBOARD SHOE & LINING 11. BUSHING 18. PISTON ASSEMBLY 26. WEAR SENSOR
12. CALIPER HOUSING 19. TWO
WAY CHECK VALVE 27. OUTBOARD SHOE & LINING 6. SLEEVE 13. SHAFT SEAL 20. BLEEDER SCREW 28. SHOE DAMPENING SPRING 7. BUSHING 14. THRUST WASHER 21. ANTI.FRICTION WASHER 37. DAMPER HM0001-566-F
Fig. 1 Rear Disc Brake Caliper Assembly

e Remove lug nuts securing rotor to hub.
e Lower car.
o Torque lug nuts. See WHEELS AND
TIRES.
SHOE AND LINING ASSEMBLIES
Figures 5 thru 8
Remove or Disconnect
1. Caliper as previously described.
2 Outboard shoe and lining (27) (Figure 5).
Install or Connect
1. Lubricated new bushings (7 and 11) (Figure 5).
2. Lubricated new two-way check valve (19) into
end of piston (18) (Figure 8).
3. Inboard shoe and lining (25). Slide edge of metal
shoe under ends of dampening spring (28) and
snap shoe into position against piston. Back of
shoe must lay flat against piston (Figure 6).
Fig. 6 Installing Inboard Shoe and Lining
26. WEAR SENSOR 25. INBOARD SHOE & 27. OUTBOARD SHOE & LINING
ASE (OR EQUIVALENT)
Fig. 5 Shoe & Linings Assemblies
3. Inboard shoe and lining (25) (Figure 6).
4. Bushings (7 and 11) from grooves in mounting
bolt holes (Figure 5).
5. Two-way check valve (19) from end of piston (18)
using small screwdriver (Figure 8). D-shaped
tab (33) on shoe must engage
D-shaped notch (32) in piston. If tab and
hole do not line up, turn piston with spanner
wrench
J 7624 or equivalent (Figure 6).
r, Wear sensor (26) should be at leading edge
of shoe during forward wheel rotation
(Figure 5).
4. Outboard
shoe and lining (27). Back of shoe must
lay flat against caliper (Figure
5).
5. Caliper as previously described.
6. Apply approximately 778
N (175 lb.) force three
times to brake pedal to seat linings.
7. Position
12-inch channel lock pliers over brake
shoe ears and bottom edge of caliper (12). While
holding moderate force
(50 lb.) on brake pedal,
clinch outboard shoe (27) (Figure 7).
NOTICE: If leakage is noted form piston hole
after check valve is removed, overhaul caliper as
specified.

ENGINE COOLING 6B-15
1. 27 N-m (20 LBS. FT.)
2. 34 N.m (25 LBS. FT.)
Fig. 602 Thermostat - V.I.N. E, F and 8
ELECTRIC COOLING FAN
CAUTION: Keep hands, tools, and
clothing away from engine cooling fan
to help prevent personal injury. This
fan is electric and can come on
whether or not the engine is running.
The fan can start automatically in
response to a heat sensor with the
ignition in the "On" position.
Remove or Disconnect
1. Negative battery cable.
2. Harness from fan motor and fan frame.
3. Fan
frame to radiator support attaching bolts.
4. Fan and frame assembly.
Install or Connect
1. Fan and frame assembly.
2. Fan frame to radiator support attaching bolts and
torque to specification.
3. Harness
to fan frame and fan motor.
4. Negative battery cable.
Inspect
For proper completion of repairs.
For operation of fan motor.
WATER PUMP
Remove or Disconnect
1. Battery negative cable at battery.
2. Cooling system.
3. If equipped with M.F.I., remove air intake tube
and mass air flow sensor.
4. Fan and radiator upper support, as applicable.
5. Serpentine belt.
6. Generator upper and lower brackets, A/C brace
and bracket and, if equipped, power steering
pump lower bracket from water pump and swing
aside.
7. Radiator lower hose and heater hose from water
Pump.
8. Water pump to block attaching bolts and remove
water pump.
Install or Connect
s If installing a new water pump, transfer
heater hose fitting from old unit.
With clean sealing surfaces on both block and water
pump, install water pump to block with new gaskets
and retain with attaching bolts. Torque to specifica-
tions. (V6 small bolt
10N.m, 7 lb. ft., large bolt and
nut 20
N-m, 15 lb. ft.) (V8-40 Nsm, 30 lb. ft.)
Radiator lower hose and heater hose to water pump
and torque clamps to 2
N.m (20 lb. in.).
Generator upper and lower brackets and, if
equipped, the power steering pump lower bracket to
the water pump. Torque bolts to 41
N.m (30 lb. in.).
Serpentine belt.
If equipped with M.F.I., install air intake tube
and mass air flow sensor.
Fan and radiator upper support, as applicable.
Battery negative cable.
Fill cooling system with an ethylene glycol
antifreeze and water mixture of
50/50.
Start engine and run, with radiator cap removed,
until radiator upper hose becomes hot
(thermostat open).
With engine idling, add coolant to radiator until
level reaches bottom of filler neck.
Cap, making sure arrows line up with overflow
tube.
Fig. 603 Fan Mounting V.I.N. E, S (All) F, 8 (wlo A/C)

6C-2 ENGINE FUEL
components such as the accelerator pumps and/or
air-fuel mixture leaning effects.
Various types and concentrations of alcohols are
used in commercial gasoline. Some alcohols are more
detrimental to fuel system components than others. If
an excessive amount of alcohol in the fuel is suspected
as the cause of a driveability condition, the following
procedure may be used to detect the presence of
alcohol in the fuel.
In this procedure, water is used to
extract the alcohol from the fuel. However, the specific
type of alcohol is not determined.
The fuel sample should be drawn from the
bottom part of the tank so that any water, if already
present, can be detected. The sample should be bright
and clear. If the sample appears cloudy or
contaminated with water as indicated by a water layer
in the bottom part of the sample, this procedure should
not be used. The fuel system should then be cleaned
(See Fuel System Cleaning).
Testing Procedure
1. Using a 100 ml cylinder with 1 ml graduation
marks, fill with fuel to the 90 ml mark.
2. Add 10 ml of water to bring the total fluid volume
to 100 ml and install a stopper.
3. Shake vigorously for 10 to 15 seconds.
4. Carefully loosen stopper to release pressure.
5. Close the stopper and shake vigorously again for
10 to 15 seconds.
6. Carefully loosen
stopper to release pressure.
7. Put the graduated cylinder on a level surface for
approximately 5 minutes to allow adequate liquid
separation.
If alcohol is present in the fuel, the volume of the
lower layer, which would now contain alcohol and
water will be greater than 10 ml. For example, if the
volume of the lower layer is increased to 15 ml, it
would indicate at least 5 percent alcohol in fuel. The
actual amount of alcohol may be somewhat greater
because this procedure does not extract all of the
alcohol from the fuel.
FUEL METERING
Throttle Body lnjection
(TBI)
With Throttle Body Injection (TBI), an injection
unit is placed on the intake manifold where the
carburetor is normally mounted. The TBI unit is
computer controlled and supplies the correct amount
of fuel during all engine operating conditions. See
Section 6E2 for information relative to operation and
diagnosis of TBI units.
Port Fuel lnjection
The ECM is in complete control of this fuel
delivery system during all driving conditions.
The intake manifold is used only to let air into the
engine. Fuel is injected by separate injectors that are
mounted over the intake valve.
With the Port Injection System, there is no need
for a Thermac, EFE, Map Sensor, Baro Sensor, A.I.R.
System, or Dual Bed Converter. This
system provides better cold driveability,
lower exhaust emissions and better throttle response.
In Sequential Fuel Injection systems (SFI),
injectors turn on at every crankshaft revolution. The
ECM controls the injector "on" time so that the
correct amount of fuel is metered, depending on
driving conditions.
Two interchangeable
"0" rings are used on the
injector that must be inspected when the injectors are
removed. Check
"0" rings for cuts or other type of
damage and replace as necessary.
The air cleaner is remotely mounted near the
radiator. It is connected to the intake manifold by air
intake ducting.
Also, mounted between the air cleaner and
intake, are the mass air flow sensor and throttle body.
Cold driveability characteristics are greatly
improved with the aid of an engine coolant supply to
the throttle body for rapid warm up.
The throttle body design uses an integral Idle Air
Control to govern idle speed and a Throttle Position
Sensor (TPS). The IAC and TPS are both controlled
by the ECM.
A large diameter fuel rail is attached to the intake
manifold and supplies fuel to all the injectors.
A fuel pressure tap is located on the rail for quick
pressure checks.
Fuel is recirculated through the rail continually
while the engine is running. This removes air and
vapors from the fuel as well as keeping the fuel cool
during hot weather operation.
A fuel pressure regulator is mounted on the fuel
rail. It maintains a constant 36 psi pressure across the
injectors under all operating conditions. It is
accomplished by controlling the amount of fuel that is
recirculated back to the fuel tank, based on engine
demand.
The pressure regulator also uses an
"0" ring for
attachment. The
"0" ring used is the same one that is
used for the injectors.
Some engines also have an accumulator that is
located in the fuel feed line near the cowl area. It is used
to dampen the vibration that is caused by the
pressurized fuel and the pulsing of the injector.
See Section 6E3 for more information and
diagnosis.
Fuel Feed and Return Pipe
When replacing fuel feed and return pipes, always
replace them with welded steel tubing meeting GM
Specification
124M, or its equivalent. The replacement
pipe must use the same type of fittings as the original
pipes to ensure the integrity of the connection.
NOTICE: Do not replace fuel pipe with fuel hose
or any other type of tubing such as copper or
aluminum. Only tubing meeting the 124M
specification is capable of meeting all the pressure
and vibration characteristics necessary to ensure
the durability standard required.
Always check and replace any
"0" rings or
washers that appear damaged.