1988 PONTIAC FIERO oil

HYDRAULIC DIAGNOSIS 700.R4-49
T.C.C. SOL
(N.O. OIL
PATH) , --- --- ---,
T.C.C. SOLENOID
(COLOR ID-DK GREEN) 1988 MODELS: MCM, MTM,
PRM, TAM, TBM
Figure 49 Wiring Diagram -Type 8
I JH0037-700R4 I
Figure 50 Wiring Diagram - Type 7

70044-52 HYDRAULIC DIAGNOSIS
r3RD CLUTCH SW
POS. SOL.' TERMINAL NEG. SOL. TERMINAL
TO TERMINAL A TO TERM. D (COLOR ID-RED) (ECM GROUND)
(COLOR ID-BLACK) T.C.C.
SOL
(N.O. OIL PATH)
NORMALLY OPEN
(N.O.) NORMALLY CLOSED (N.C.)
988 MODEL: YPM
JH0174-700R4-R 1
Figure 55 Wiring Diagram - Type 16

HYDRAULIC DIAGNOSIS 700-R4-53
1 LINE 16 T.V.F.
2 D4
17 OVERRUN CLUTCH
3 D2
18 T.V. EX.
4 LO 19
D3IPART THROTTLE
5 REVERSE
20 PART THROTTLE
6 GOVERNOR
21 D3
7 LO
- 1ST FEED 22 4TH CLUTCH
I 8 LOIREVERSE 23 C.C. SIG.
9 3RD ACCUMULATOR 24 MOD. UP
10 T.V.
25 MOD. DOWN
11 M.T.V.
26 DETENT
12 ACCUMULATOR 27 3-4 CLUTCH
13 4TH SIGNAL 28
DETENTILO
14 2ND CLUTCH 29 RND4-3
15 3-4 ACCUMULATOR
30 3RD CLUTCH 3 1
IDENTIFICATION
32
VOID
33 EXHAUST
34 SF
35 4-3
42 D4 ABUSE
43 3RD FEED
44 3-2
HIGH SPEED
45 2ND FEED
46 3RD CL. EXHAUST
47 4TH FEED
48 1-2 ACCUMULATOR
I JH0042-700R4 I Figure 56 Valve Body Oil Passages

700.R4.54 HYDRAULIC DIAGNOSIS
NON ECM 1
CONTROLLED I I VEHICLES I ONLY I
307 306 309 L - - - - - - - - - - - - -
301 VALVE. T.V. MODULATOR DOWNSHIFT
302 SPRING, T.V. MODULATOR DOWNSHIFT
VALVE
303 VALVE, T.V. MODULATOR UPSHIFT
304 SPRING, T.V. MODULATOR UPSHIFT
VALV1. 305 SLEEVE, CONVERTER CLUTCH THROTTLE
306 SPRING, CONVERTER CLUTCH THROTTLE
307 VALVE, CONVERTER CLUTCH THROTTLE
308 VALVE, CONVERTER CLUTCH SHIFT
309 SLEEVE, 3-4 THROTTLE VALVE
310 SPRING, 3-4 THROTTLE VALVE
31 1 VALVE, 3-4 THROTTLE
3
1 2 VALVE, 3-4 SHIFT
313 SLEEVE, 2-3 THROTTLE VALVE
314 SPRING, 2-3 THROTTLE VALVE
3 15 VALVE, 2-3 THROTTLE
31 6 VALVE, 2-3 SHIFT
31
7 SLEEVE, 1-2 THROTTLE VALVE
31 8
SPRING, 1-2 THROTTLE VALVE
3 1 9 VALVE, 1-2 THROTTLE
322 VALVE, 1-2 SHIFT
323 SLEEVE, THROTTLE VALVE PLUNGER
324 PLUNGER, THROTTLE VALVE
325 SPRING, THROTTLE VALVE
326 VALVE, THROTTLE 328
VALVE, 3-4 RELAY
329 VALVE, 4-3 SEQUENCE
330 SPRING, 4-3 SEQUENCE VALVE
331 SPRING, T.V.
LlMlT VALVE
332 VALVE, T.V. LlMlT
333 VALVE, 1-2 ACCUMULATOR
334 SLEEVE, 1-2 ACCUMULATOR VALVE
335 SPRING, 1-2 ACCUMULATOR VALVE
336 VALVE,
LlNE BIAS
337 SPRING, LlNE BIAS \IALVE
338 SPRING, 3-2 CONTROL
339 VALVE, 3-2 CONTROL
340 VALVE, MANUAL
341 PIN, COILED SPRING
342 PIN, COILED SPRING
343 RETAINER, SPRING (SLEEVE)
344 PLUG. VALVE BORE
350 BODY, CONTROL VALVE 351 PLUG, T.V. LlMlT
352 PLUG, VALVE BORE (12.5 - O.D.) 354 PLUG, CONVERTER CLUTCH SHIFT VALVE
BORE (ECM CONTROLLED VEHICLES)
355 PLUG, CONVERTER CLUTCH T.V. BUSHING
BORE (ECM CONTROLLED VEHICLES)
JH0043-700R4
Figure 57 Valve Trains

700-R4-58 HYDRAULIC DIAGNOSIS
LlNE
D4
D 2
LO REVERSE
GOVERNOR
LO
- 1 ST FEED
LOIREVERSE
3RD ACCUMULATOR
T. V.
M.T.V.
ACCUMULATOR
(4TH)
4TH SIGNAL
2ND CLUTCH
3-4 ACCUMULATOR
T.V.F.
OVERRUN CLUTCH
T.V. EX.
D3lPART THROTTLE
PART THROTTLE
D 3
~TH CLUTCH
C.C. SIG.
MOD. UP
MOD. DOWN
DETENT
3-4 CLUTCH (3-2 EX)
DETENTILO
RND4-3
1-2 ACCUMULATOR
lure 6 1 Case Oil Passages and Checkball Locations
1 LINE 27 3-4 CLUTCH
3 DR-2
32
VOID 5 REVERSE 36 VENT
11 M.T.V. 39(a) LUBE TO COOLER
17 O.R. CLUTCH 39(b) LUBE FROM COOLER
23 CONV. CL.
SIG. 49 PRESSURE TAP
I JH0048-700R4 I Figure 62 Pump to Case Oil Passages A
CASE SERVO BORE
B SERVO EXHAUST HOLE
C 2ND
& 4TH BAND APPLY PASSAGE
D 3RD ACCUMULATOR PRESSURE TAP PASSAGE
80 RETAINER & BALL ASSEMBLY, 3RD ACCUM.
86 PLUG, CASE SERVO
1 JH0049-700R4 I Figure 63 Servo Oil Passages

HYDRAULIC DIAGNOSIS 700-R4-59
A 4TH OIL 21 SEAL, "0" RING
B 3RD ACCUMULATOR OIL 22 HOUSING, SERVO PISTON (INNER) C VALVE BODY FACE
23 RING,
OIL SEAL (2ND APPLY PISTON) (INNER)
D OIL PAN FLANGE
24 RING, OIL SEAL
(2ND APPLY PISTON) (OUTER)
E EXHAUST 25 PISTON, 2ND APPLY
F 2ND OIL
26 S'PRING, SERVO CUSHION
14 SEAL, "0" RING (2-4 SERVO COVER)
27 RETAINER, SERVO CUSHION SPRING 15 COVER, 2-4 SERVO 28 RING, RETAINER (2ND APPLY PISTON)
16 PISTON, 4TH APPLY
29 PIN, 2ND APPLY PISTON
17 RING, OIL SEAL (4TH APPLY PISTON)
31 SPRING, SERVO RETURN
(OUTER) 80 RETAINER
81 BALL ASSEMBLY, 3RD ACCUM.
18 RING, RETAINER (APPLY PIN) 86 PLUG, CASE SERVO
19 WASHER, SERVO APPLY PIN
20 SPRING, SERVO APPLY PIN JH0050.700R4
Figure 64 Servo Assembly

700-R4-60 HYDRAULIC DIAGNOSIS
I JH0051-700R4 I
Figure 65 Pump Cover Oil Passages
Figure
66 Pump Body Oil Passages

TORQUE CONVERTER CLUTCH (TCC)
DIAGNOSIS
To properly diagnose the Torque Converter
Clutch (TCC) system, perform all electrical
testing first and then the hydraulic testing. Refer
to the Torque Converter Section
6E2-C8 for
additional information.
The TCC is applied by fluid pressure which is
controlled by a solenoid located inside the Automatic
Transmission assembly. The solenoid is energized or
released by making or breaking an electrical circuit
through a combination of switches and sensors.
TCC Electrical Diagnosis
e For electrical diagnosis of TCC, refer to the
specific vehicle section in Section
8A, Electrical
Diagnosis.
e For diagnosis of emission control related
components of TCC, Refer to the specific section
of
6E, Driveability and Emissions.
e For the diagnosis of TCC Hydraulic Controls,
refer to the Procedure and Wiring Diagrams
provided in this section.
Functional Check Procedure
rn Inspect
1. Install a tachometer
2. Operate the vehicle until proper operating
temperature is reached
3. Drive vehicle at 50-55 mph (80-88 Km/h) with
light throttle (road load)
4. Maintaining throttle lightly touch the brake
pedal and check for a slight bump when the TCC
releases and a slight increase in engine RPM.
5. Release the brake, slowly accelerate and check for
a re-apply of the converter clutch and a slight
decrease in engine RPM.
Preliminary Checking Procedure
The purpose of the preliminary checking
procedure is to isolate external (electrical) problems
from internal (electrical or mechanical) ones.
Important
e Use only a scale type ohmmeter. High impedance
type ohmmeters and those with a digital readout
will not work.
e An ALCL scanner may be used to verify the
electrical circuit. Remember, a completed circuit
does not indicate that the solenoid will apply.
e Do not bench test using an automotive type
battery. Accidentally crossed wires will damage
the internal diodes of the TCC solenoid.
HYDRAULIC DIAGNOSIS 700-R4-61
External Controls
rn Inspect
e Connect voltmeter between transmission
connector and ground.
e Turn key "ON"
e If 0 or low voltage is found, refer to Sections 6E
and 8A for electrical diagnosis.
e If 12 volts are present at the connector, refer to
the TCC hydraulic diagnosis.
TORQUE CONVERTER EVALUATION
Torque Converter Stator
The Torque Converter Stator roller clutch can
have one of two different type malfunctions:
A. Stator Assembly freewheels in both
directions.
B. Stator Assembly remains locked up at all
times.
Condition A-Poor Acceleration Low Speed
The vehicle tends to have poor acceleration from
a standstill. At speeds above 30-35 mph (50-55
km/h),
the car may act normal. If poor acceleration is noted,
it should first be determined that the exhaust system
is not blocked, the engine timing is correct and the
transmission is in first
(1st) gear when starting out.
If the engine freely accelerates to high
r.p.m. in
"NEUTRAL" (N), it can be assumed that the engine
and exhaust system are normal. Checking for poor
performance in "Drive" and Reverse will help
determine if the stator is freewheeling at all times.
Condition B-Poor Acceleration High Speed
Engine r.p.m. and car speed limited or restricted
at high speeds. Performance when accelerating from a
standstill is normal. Engine may over-heat. Visual
examination of the converter may reveal a blue color
from over-heating.
If the converter has been removed, the stator
roller clutch can be checked by inserting a finger into
the splined inner race of the roller clutch and trying to
turn the race in both directions. The inner race should
turn freely clockwise, but not turn or be very difficult
to turn counterclockwise.
The Converter Should Be Replaced If:
e Leaks externally, such as at the hub weld area.
e Converter has an imbalance which cannot be
corrected. (Refer to Converter Vibration Test
Procedure).
e Converter is contaminated with engine coolant
containing antifreeze.
The Converter Should Not Be Replaced If:
e The oil has an odor, is discolored, and there is no
evidence of metal or clutch facing particles.
e The threads in one or more of the three converter
bolt holes are damaged.
- Correct with thread insert. (Refer to Section
6A).