GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 287
DRIVE TRAIN
MANUAL TRANSMISSION
UNDERSTANDING THE MANUAL TRANSMISSION
Because of the way an internal combus tion engine breathes, it can produce
torque (or twisting force) only withi n a narrow speed range. Most overhead
valve pushrod engines must turn at about 2500 rpm to produce their peak
torque. Often by 4500 rpm, they are prod ucing so little torque that continued
increases in engine speed produce no power increases.
The torque peak on overhead camshaft engines is, generally, much higher, but
much narrower.
The manual transmission and clutch are employed to vary the relationship
between engine RPM and the speed of the w heels so that adequate power can
be produced under all circumst ances. The clutch allows engine torque to be
applied to the transmission input shaft gradually, due to mechanical slippage.
The vehicle can, consequently, be star ted smoothly from a full stop.
The transmission changes the ratio between the rotating speeds of the engine
and the wheels by the use of gears. 4-speed or 5-speed transmissions are most
common. The lower gears al low full engine power to be applied to the rear
wheels during acceleration at low speeds.
The clutch driveplate is a thin disc, the center of which is splined to the
transmission input shaft. Both sides of the disc are covered with a layer of
material which is similar to brake li ning and which is capable of allowing
slippage without roughness or excessive noise.
The clutch cover is bolted to the engine flywheel and incorporates a diaphragm
spring which provides the pressure to engage the clutch. The cover also houses
the pressure plate. When the clutch pe dal is released, the driven disc is
sandwiched between the pressu re plate and the smooth surface of the flywheel,
thus forcing the disc to turn at th e same speed as the engine crankshaft.
The transmission contains a mainshaft which passes all the way through the
transmission, from the clutch to the dr iveshaft. This shaft is separated at one
point, so that front and rear portions can turn at different speeds.
Power is transmitted by a countershaft in the lower gears and reverse. The
gears of the countershaft mesh with gear s on the mainshaft, allowing power to
be carried from one to the other. Countershaft gears are often integral with that
shaft, while several of the mainshaft gea rs can either rotate independently of
the shaft or be locked to it. Shifting from one gear to the next causes one of the
gears to be freed from rotating with the shaft and locks another to it. Gears are
locked and unlocked by internal dog clutc hes which slide between the center of
the gear and the shaft. The forward gears us ually employ synchronizers; friction
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 306
As the speed of the turbine increases, th
e fluid spins faster and faster in the
direction of engine rotation. As a result, t he ability of the stator to redirect the
fluid flow is reduced. Under cruising conditions, the stator is eventually forced to
rotate on its one-way clutch in the dire ction of engine rotation. Under these
conditions, the torque converter begins to behave almost like a solid shaft, with
the torus and turbine speeds being almost equal.
PLANETARY GEARBOX
The ability of the torque converter to mult iply engine torque is limited. Also, the
unit tends to be more efficient when the turbine is rotating at relatively high
speeds. Therefore, a planetar y gearbox is used to carry the power output of the
turbine to the driveshaft.
Fig. 2: Planetary gears work in a sim ilar fashion to manual transmission gears,
but are composed of three parts
Planetary gears function very similarly to conventional transmission gears.
However, their construction is different in that three elements make up one gear
system, and, in that all three elements ar e different from one another. The three
elements are: an outer gear that is shaped like a hoop, with teeth cut into the
inner surface; a sun gear, mounted on a sha ft and located at the very center of
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 309
Fig. 5: Servos, operated by pressure, ar e used to apply or release the bands, to
either hold the ring gear or allow it to rotate
The accumulators are used to cushi on the engagement of the servos. The
transmission fluid must pass through the ac cumulator on the way to the servo.
The accumulator housing contains a thin piston which is sprung away from the
discharge passage of the accumulato r. When fluid passes through the
accumulator on the way to the servo, it must move the piston against spring
pressure, and this action smooths out the action of the servo.
HYDRAULIC CONTROL SYSTEM
The hydraulic pressure used to operat e the servos comes from the main
transmission oil pump. This fluid is channel ed to the various servos through the
shift valves. There is generally a manual shift valve which is operated by the
transmission selector lever and an automat ic shift valve for each automatic
upshift the transmission provides.
Many new transmissions are electroni cally controlled. On these models,
electrical solenoids are used to better control the hydraulic fluid. Usually, the
solenoids are regulated by an electronic control module.
There are two pressures which affect t he operation of these valves. One is the
governor pressure which is effected by vehicle speed. The other is the
modulator pressure which is effected by intake manifold vacuum or throttle
position. Governor pressure rises wit h an increase in vehicle speed, and
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 312
4. Rotate the shift lever clockwis
e to the park detent and then back to
neutral.
5. Tighten cable attachment to 11 ft. lbs. (15 Nm).
The lever must be held out of P when tightening the nut.
SHIFT LINKAGE 1. Place the manual shaft of the transmission in N. Place the console shift
lever in N.
2. Install the cable in the slot of the shift lever. Adjust the cable so that the
pin has free movement.
3. Install and tighten t he nut to the pin.
THROTTLE VALVE CABLE 1. After installation of the cable to the transmission, engine bracket, and the
cable actuating lever, check to assure that the cable slider is in the zero
or fully re-adjusted position.
2. If cable slider is not in zero or fully re-adjusted, depress and hold the
metal re-adjust tab. Move the sli der back through the fitting in the
direction away from the cable actuat ing lever until the slider stops against
the fitting. Release the metal re-adjust tab.
Fig. 3: TV cable and linkage
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 364
5. Drain the radiator and remove t
he radiator hoses. Disconnect the heater
hoses and the transmission cooler lines.
6. Remove the upper half of the radi ator shroud, if equipped with a manual
transmission. Remove the radiator and fan shroud assembly, if equipped
with an automatic transmission.
7. Disconnect the throttle linkage, includi ng the cruise control detent cable.
8. Remove the air conditioning compressor and lay aside.
Do not disconnect the air conditioning lines.
9. Disconnect the power steering pump and drain the fluid into a suitable
container. Remove the vacuum brake booster line.
10. Remove the distributor cap and spark plug wires.
11. Disconnect the engine electrical connection at the bulkhead connection
and disconnect any necessary vacuum hoses.
12. Working inside the vehicle, re move the right-hand hush panel and
disconnect the ECM harness at the EC M. Raise and safely support the
vehicle. Remove the right fenderwell splash shield and feed the harness
through the fenderwell.
13. Disconnect the exhaust pipes at the exhaust manifolds and remove
exhaust system from the vehicle.
14. Remove the flywheel cover and remo ve the converter bolts, if equipped
with automatic transmission.
15. Disconnect the transmission an d starter wire connections.
16. Remove the bellhousing and t he motor mount through-bolts.
17. Disconnect the clutch fork return spring, if equipped with a manual
transmission. Lower the vehicle.
18. Relieve the fuel system pressu re. Disconnect the fuel lines.
19. Support the transmission with a suit able jack. Attach an engine lifting
device.
20. Remove the engine assembly.
To install: 21. Position the engine assembly in the vehicle.
22. Attach the motor mount to engine br ackets and lower the engine in place.
Remove the engine lifting device and the transmission jack.
23. Raise and support the vehicle safely.
24. Install the motor mount through-bolts and tighten the nuts to specification. Install t he bellhousing bolts and tight en to 35 ft. lbs. (47
Nm).
25. On vehicles with automatic transmissi on, install the converter to flywheel
attaching bolts to 46 ft. lbs. (63 Nm).
26. Install the flywheel splash shield and tighten to 89 inch lbs. (10 Nm).
Install the clutch return spring, if equipped with manual transmission.
27. Connect the starter wires and the fuel lines.
28. Install the exhaust system.
29. Lower the vehicle.
30. Install the power steering pump and the air conditioning compressor.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 451
Fig. 3: One-piece seal installation
1. Jack up your vehicle and support it with jackstands.
2. Remove the transmission.
3. If equipped with a manual transmission, remove the clutch and pressure
plate.
4. Remove the flywheel assembly.
5. Using a suitable tool, pry the old seal out.
6. Inspect the crankshaft for nicks or burrs, correct as required.
To install: 7. Clean the area and coat the seal with eng ine oil. Install the seal onto tool
J-34686 or equivalent. Install the seal into the engine.
8. Install the flywheel and torque to specification.
9. Install the transmission. (If equipped with a manual transmission, install
the clutch and pressure plate first.)
10. Check the fluid levels, star t the engine and check for leaks.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 581
Fig. 1: Coolant temperature sensor. The in take air temperature sensor is similar
in appearance
IDLE AIR CONTROL (IAC) VALVE
OPERATION
Engine idle speeds are controlled by the ECM through the IAC valve mounted
on the throttle body. The ECM sends volt age pulses to the IAC motor windings
causing the IAC motor shaft and pintle to move IN or OUT a given distance
(number of steps) for each pulse (called counts). The movement of the pintle
controls the airflow around the throttle plat e, which in turn, controls engine idle
speed. IAC valve pintle position counts ca n be observed using a scan tool. Zero
counts correspond to a fully closed passage, while 140 counts or more
corresponds to full flow.
Idle speed can be categorized in 2 ways : actual (controlled) idle speed and
minimum idle speed. Contro lled idle speed is obtained by the ECM positioning
the IAC valve pintle. Resulting idle speed is determined by total air fl\
ow
(IAC/passage + PCV + throttle valve + ca librated vacuum leaks). Controlled idle
speed is specified at normal operating c onditions, which consists of engine
coolant at normal operating temper ature, air conditioning compressor OFF,
manual transmission in neutral or automatic transmission in D.
Minimum idle air speed is set at t he factory with a stop screw. This setting
allows a certain amount of air to bypas s the throttle valves regardless of IAC
valve pintle positioning. A co mbination of this air flow and IAC pintle positioning
allows the ECM to control engine idle speed. During normal engine idle
operation, the IAC valve pintle is positioned a calibrated number of steps
(counts) from the seat. No adjustment is required during routine maintenance.
Tampering with the minimum idle speed adjustment may result in premature
failure of the IAC valve or imprope rly controlled engine idle operation.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 623
1988-1992 5.0L THROTTLE BODY INJECT
ION; MANUAL TRANSMISSION
1988-1992 5.0L THROTTLE BODY INJECTION; AUTO TRANS.