1988 PONTIAC FIERO transmission

6E-14 DRIVEABILITY AND EMISSIONS - FUEL INJECTION
N.O. - NORMALLY OPEN - State of relay contacts
or solenoid plunger when no voltage
is applied.
NOx - NITROGEN, OXIDES OF - One of the
pollutants found in engine exhaust.
O2 - OXYGEN (Sensor) - Monitors the oxygen
content of the exhaust system and generates a voltage
signal to the ECM.
OIL or OILOOP - OPEN LOOP - Describes ECM fuel
control without use of oxygen sensor information.
OUTPUT - Result of a function typically controlled
by the ECM.
OXYGEN SENSOR. EXHAUST - Device that detects
the amount of oxygen
(02) in the exhaust stream.
P.A.1.R - PULSE AIR INJECTION REACTOR system -
pulsed air directed into engine to reduce exhaust
emissions.
PCV - POSITIVE CRANKCASE VENTILATION -
Prevent fumes in crankcase from passing into
atmosphere.
PFI - PORT FUEL INJECTION
PIN
- PARWNEUTWL
PORT - EXHAUST OR INTAKE PORT
PROM
- PROGRAMABLE READ ONLY MEMORY-
an electronic term used to describe the engine
calibration unit
.
RPM - REVOLUTIONS PER MINUTE - A measure of
rotational speed.
RVB - REAR VACUUM BMKE - is used to control
choke operation during cold engine conditions.
SELF-DIAGNOSTIC CODE - The ECM can detect
malfunctions in the system.
If a malfunction occurs,
the ECM turns on the "Service Engine Soon" light.
A
diagnostic code can be obtained from the ECM
through the "Service Engine Soon" light, or by use of a
"Scan" tool. This code will indicate the area of the
malfunction.
SES - SERVICE ENGINE SOON LIGHT - Lights when
a malfunction occurs in Computer Command Control
system.
TACH - TACHOMETER
TBI
- THROTTLE BODY INJECTION (Unit) - is
controlled by the ECM to supply precise airlfuel
mixture into the intake manifold.
TCC - TWNSMISSION I TRANSAXLE CONVERTER
CLUTCH
- ECM controlled solenoid in transmission
which positively couples the transmission to the
engine.
THERMAC - THERMOSTATIC AIR CLEANER -
provides preheated air to intake manifold to provide
better driveability when engine
is cold.
TPS - THROnLE POSITION SENSOR - Device that
tells the ECM the throttle position.
TVS - THERMAL VACUUM SWITCH - Used to
control vacuum in relationship to engine temperature.
V - VOLT
V-6 - SIX CYLINDER ENGINE - Two banks of
cylinders, arranged in a
"V".
V-8 - EIGHT CYLINDER ENGINE - Two banks of
cylinders, arranged in a
"V".
VACUUM - Negative pressure; less than
atmospheric pressure.
VACUUM, MANIFOLD - Vacuum source in
manifold below throttle plate.
VACUUM, PORTED - A vacuum source above I (atmospheric side ) of closed throttle plate. , I
WAC SENSOR - Abbreviation for differential
pressure sensor which is a
vacuum sensor.
VIN - VEHICLE IDENTIFIUTION NUMBER. 1
VSS - VEHICLE SPEED SENSOR - Sensor which
sends vehicle speed information to the ECM.
WASTECATE - A means of controlling the amount
of boost available for a Turbo charged engine.
WOT- WIDE OPEN THROPTLE. I
WIRING HARNESS SERVICE I
The ECM wire harness electrically connects the
ECM to the various solenoids, switches, and sensors in
vehicle engine compartment. The ECM is located
inside the vehicle passenger compartment.
Most connectors in the engine compartment are
protected against moisture and dirt which could create
oxidation and deposits on the terminals. This
protection is important because of the very low voltage
and current levels found in the electronic system. The
connectors have a lock which secures the male and
female terminals together. A secondary lock holds the
seal and terminal into the connector.
GENERAL
Molded-on connectors (like Metri-Pack) require
complete replacement of the connector. This means
splicing a new connector assembly into the harness.

EXHAUST SYSTEM 6F-3
1. MANIFOLD 8. INTERMEDIATE EXHAUST 13. CONVERTER ASSEMBLY 2. SEAL PIPE ASSEMBLY 14. 60 Nvrn (44 LBS. FT.)
3. CROSSOVER PIPE 9. 50 N-rn (37 LBS. FT.) 15. FRONT EXHAUST 4. 20 N-m (15 LBS. FT.) 10. HANGER PIPE
5. UNDERBODY 11. INNER BRACKET
6. 10 N-m (8 LBS. FT.) ASSEMBLY
7. MUFFLER 12. TRANSMISSION
J10001-6F-F
Fig. 5 Exhaust System - V.I.N. S

1. UNDERBODY
2. 10
N.rn (8 LBS. FT.)
3. MUFFLER
4. INTERMEDIATE EXHAUST
5. 60 Nern (44 FT. LBS.)
6. CONVERTER ASSEMBLY
7. 20
N-rn (15 FT. LBS.)
8. 50 N-rn (37 LBS. FT.)
9. TRANSMISSION
10. FRONT EXHAUST
PlPE
11. MANIFOLD
12. CROSSOVER
PlPE
13. SPACER
Fig. 6 Exhaust System - V.I.N. F, E and 8

HYDRAULIC DIAGNOSIS 700.R4-1
SECTION 700-R4
AUTOMAT C TRANSM
CONTENTS
GENERAL DESCRIPTION
The THM 700-R4 is a fully automatic
transmission for rear wheel drive vehicles which
provides four forward gear ranges and a reverse.
The major components of this transmission are:
e Torque Converter Clutch Asm.
e Vane Type Oil Pump
e 2-4 Band Asm.
e Five Multiple Disc Clutches
0 Two Planetary Gear Sets
0 One Sprag Clutch
0 One Roller Clutch
e Valve Body Asm.
The oil pressure and shift points are controlled by
throttle opening via a throttle valve cable. (See Section
7A1 for T.V. cable information).
The transmission can be operated in any one of
the following seven modes:
P
- Park position prevents the vehicle from rolling
either forward or backward. (For safety reasons the
parking brake should be used in addition to the park
position).

700-R4-2 HYDRAULIC DIAGNOSIS
R - Reverse allows the vehicle to be operated in
a rearward direction.
N - Neutral allows the engine to be started and
operated without driving the vehicle. If necessary this
position may be selected if the engine must be restarted
with the vehicle moving.
D - Overdrive is used for all normal driving
conditions. It provides four gear ratios plus converter
clutch operation. Downshifts are available for safe
passing by depressing the accelerator.
D - Drive position is used for city traffic, hilly
terrain, and trailer towing. It provides three gear
ranges. Again, downshifts are available by depressing
the accelerator.
2 - Manual second is used to provide acceleration
and engine braking. This range may be selected at any
vehicle speed.
1 - Manual Lo is used to provide maximum
engine
brlking. This range may also be selected at any
vehicle speed.
DIAGNOSIS INFORMATION
ROAD TEST PROCEDURE
e Perform the road test following the sequence
given
e MPH (KPH) shift points will vary with actual
throttle position and driver habits
e Compare the results of the test with speed shift
chart information. Use these results with the
diagnosis information contained in this
Automatic Transmission Hydraulic Diagnosis
Section to evaluate the transmission.
e This test should only be performed when traffic
and road conditions permit
e Observe all traffic safety regulations
Drive and Reverse Engagement Shift Check
1. Start engine
2. Depress brake pedal
3. Move gear selector:
- "Park" (P) to "Reverse" (R)
- "Reverse" (R) to "Neutral"
(N) to "Drive" (D)
Gear selections should be immediate and
not harsh.
Upshifts and Torque Converter Clutch (TCC)
Apply (Figure
2)
With gear selector in "Overdrive" (D)
1. Accelerate using a steady increasing throttle
pressure
2. Note the shift speed point gear engagements for:
- 2nd gear
- 3rd gear
- Overdrive
3. Note the speed shift point for TCC apply. This
should occur while in third gear or overdrive. If
the apply is not noticed, refer to the Preliminary
Torque Converter Clutch Diagnosis information
contained in this section of the Service Manual.
Important
The torque converter clutch will not engage if
engine coolant has not reached a minimum
operating temperature of approximately 54°C
(1 30°F).
Part Throttle Downshift
At vehicle speeds of 40-55 MPH (64-88
KPH) quickly depressed the accelerator to
a half open position and observe:
- TCC releases
- Transmission downshift to 3rd gear
immediately
Full Throttle (Detent) Downshift
At vehicle speeds of 48-55 MPH (77-88
KPH) quickly depress the accelerator to a
wide open position and observe:
- TCC releases
- Transmission downshifts to 2nd gear
immediately
Manual Downshift
1. At vehicle speeds of 40-55 MPH (64 to 88 KPH)
release the accelerator pedal while moving the
gear selector to "Third" gear (D) and observe:
- TCC release
- Transmission downshift to 3rd gear should
be immediate
- Engine should slow vehicle down
2. Move gear selector to "Overdrive" and accelerate
to 40-45 MPH (64-72 KPH). Release the
accelerator pedal while moving the gear selector
to "Second" gear (2) and observe.
- TCC release
- Downshift to second gear should be
immediate
- Engine should slow vehicle down
3. Move gear selector to "Overdrive" (D) and
accelerate to 25 MPH (40 KPH). Release the
accelerator pedal while moving the gear selector
to "First" gear (1) and observe:
- TCC release
- Transmission downshift to 1st gear should
be immediate
- Engine should slow vehicle down
Coastdown Downshift
1. With the gear selector in "Overdrive" (D)
accelerate to 4th gear with TCC applied.
2. Release the accelerator pedal and lightly apply
the brakes to observe:
- TCC release
- Shift points for downshifts.
Manual Gear Range Selection
MANUAL THIRD (D)
1. With vehicle stopped, place gear selector in
"Third" (D) and accelerate to observe:

HYDRAULIC DIAGNOSIS 700434-3
- The first to second gear shift point
- The second to third gear shift point
MANUAL SECOND (2)
2. With vehicle stopped, place gear selector in
"Second" (2) and accelerate to observe:
- The first to second gear shift point
3. Accelerate to 25 MPH (40 KPH) and observe:
- That a second to third gear shift does not
occur
- That TCC does not engage
MANUAL FIRST (I)
1. With vehicle stopped, place gear selector in
"First" (1) and accelerate to 15 MPH (24
KPH)
and observe:
- That no uoshift occurs
- That TCC does
REVERSE
1. With
vehicle stopped, place gear selector in
"Reverse" (R) and slowly accelerate to observe
reverse gear operation.
All possible throttle positions and corresponding
MPH shift point information has not been
provided.
TRANSMISSION PRESSURE CHECK
PROCEDURE
Inspect
e Fluid level
e TV cable adjustment
e Manual linkage
e Engine mechanical, emissions, electrical and fuel
delivery systems
not engage
Install or Connect (Figure 3)
a Oil pressure gage
a Tachometer

700-R4-6 HYDRAULIC DIAGNOSIS
L PRESSURE CHECK NFORMAT
PRELIMINARY CHECK PROCEDURE
0 CHECK TRANSMISSION OIL LEVEL 0 CHECK AND ADJUST T.V. CABLE
0 CHECK OUTSIDE MANUAL LINKAGE AND CORRECT
@ CHECK ENGINE TUNE
0 INSTALL OIL PRESSURE GAGE
CONNECT TACHOMETER TO ENGINE
0 CHECK OIL PRESSURE AS FOLLOWS:
Minimum T.V. Line Pressure Check (A) ATTACH PRESSURE GAGE
Set the T.V. cable to specification; and with the brakes applied, take the line pressure readings in the ranges and
at the engine
r.p.m.'s indicated in the chart below.
Full T.V. Line Pressure Check Full T.V. line pressure readings are obtained by tying or holding the T.V. cable to the full extent of its travel; and with
the brakes applied, take the line pressure readings in the ranges and at the engine
r.p.m.'s indicated in the chart below.
MODEL
Line pressure is basically controlled by pump output and the pressure regulator valve. In addition, line pressure is
boosted in Reverse, Second and Lo by the reverse boost valve.
Also, in the Neutral, Drive, Intermediate and Reverse positions of the selector lever, the line pressure should increase
with throttle opening because of the T.V. system. The pressure is controlled by the T.V. cable, the throttle lever and
bracket assembly and the T.V. link, as well as the control valve assembly.
The main line pressure tap plug is located on the left side of the transmission above the outside manual lever.
Figure
4 Oil Pressure Check Procedure

700-R4-8 HYDRAULIC DIAGNOSIS
OIL LEAK - Low bolt torque.
- Cut or damaged oil pan gasket.
To Correctly Identify Oil
Leaks, Perform the Following
T.V. Cable Connector - Connector cocked and interfering with
Procedure:
- Connector cracked.
0 Clean all residual oil from - Seal missing, cut or damaged.
the transmission with
elec-
tramotive cleanser or equiv- - Fill tube cracked or damaged.
alent.
- Seal missing, cut, or damaged.
0 Dust the transmission with 0 Electrical Connector - Electrical connector cracked.
leak tracing powder or spray
- Seal missing, cut or damaged.
foot powder.
@ Manual Shaft - Manual shaft nicked or damaged.
Bring the engine to normal
- Manual shaft seal assembly missing, cut
operating temperature.
Turn the engine off and Governor Cover
- Gaps in sealant. (Remove & Reseal.)
let the vehicle set for
Speedo Fitting
- Low bolt torque.
- Seal missing, cut or damaged.
Check for leaks.
@ Servo Cover
Cooler Fittings
- Cracked fitting.
0 Converter Assembly - Hub or seam weld leak.
- Oil overfill.
- Engine coolant in transmissio
0 Oil Pump Assembly
Rear Extension
- Damaged extension to case seal.
Figure
6 Diagnosis Chart A