GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 495
Again, rotate the engine, this time
to position the number one cylinder bore
(head surface) up. Turn the crankshaft until the number one piston is at the
bottom of its travel, this should allow t he maximum access to its connecting rod.
Remove the number one co nnecting rods fasteners and cap and place two
lengths of rubber hose over the rod bolts/studs to protect the crankshaft from
damage. Using a sturdy wooden dowel and a hammer, push the connecting rod
up about 1 in. (25mm) from the cranks haft and remove the upper bearing insert.
Continue pushing or tapping the connecti ng rod up until the piston rings are out
of the cylinder bore. Remove the piston and rod by hand, put the upper half of
the bearing insert back into the rod, in stall the cap with its bearing insert
installed, and hand-tighten the cap fasteners. If the parts are kept in order in this
manner, they will not get lost and you wil l be able to tell which bearings came
form what cylinder if any problems are discovered and diagnosis is necessary.
Remove all the other piston assemblie s in the same manner. On V-style
engines, remove all of the pistons from one bank, then reposition the engine
with the other cylinder bank head surface up, and remo ve that banks piston
assemblies.
The only remaining component in the engine block should now be the
crankshaft. Loosen the main bearing ca ps evenly until the fasteners can be
turned by hand, then remove them and the caps. Remove the crankshaft fro\
m
the engine block. Thoroughly clea n all of the components.
INSPECTION
Now that the engine block and all of its components ar e clean, it's time to
inspect them for wear and/or damage. To accurately inspect them, you will need
some specialized tools:
• Two or three separate micromet ers to measure the pistons and
crankshaft journals
• A dial indicator
• Telescoping gauges for the cylinder bores
• A rod alignment fixture to check for bent connecting rods
If you do not have access to the proper tools, you may want to bring the
components to a shop that does.
Generally, you shouldn't expect cracks in the engine block or its components
unless it was known to leak, consume or mix engine fluids, it was severely
overheated, or there was ev idence of bad bearings and/or crankshaft damage.
A visual inspection should be performed on all of the components, but just
because you don't see a crack does not mean it is not there. Some more
reliable methods for inspecting for cracks include Magnaflux, a magnetic
process or Zyglo, a dye penetrant. M agnaflux is used only on ferrous metal
(cast iron). Zyglo uses a spray on fluoresce nt mixture along with a black light to
reveal the cracks. It is strongly recommended to have your engine block
checked professionally for cracks, especia lly if the engine was known to have
overheated and/or leaked or consumed coolant. Contact a local shop for
availability and pricing of these services.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 512
5. Make sure the ring gaps are pr
operly spaced around the circumference
of the piston. Fit a piston ring co mpressor around the piston and slide the
piston and connecting rod assembly do wn into the cylinder bore, pushing
it in with the wooden hammer handle. Pu sh the piston down until it is only
slightly below the top of the cylinder bore. Guide the connecting rod onto
the crankshaft bearing journal carefully, to avoid damaging the
crankshaft.
6. Check the bearing clearance of all the rod bearings, fitting them to the
crankshaft bearing journals. Follow the procedure in the crankshaft
installation above.
7. After the bearings have been fitted, apply a light coating of assembly oil
to the journals and bearings.
8. Turn the crankshaft until the appropria te bearing journal is at the bottom
of its stroke, then push the piston a ssembly all the way down until the
connecting rod bearing seat s on the crankshaft journal. Be careful not to
allow the bearing cap screws to stri ke the crankshaft bearing journals
and damage them.
9. After the piston and connecting rod assemblies have been installed, check the connecting rod side clearance on each crankshaft journal.
10. Prime and install t he oil pump and the oil pump intake tube.
CAMSHAFT, LIFTERS AND TIMING ASSEMBLY 1. Install the camshaft.
2. Install the lifters/followers into their bores.
3. Install the timing gears/chain assembly.
CYLINDER HEAD(S) 1. Install the cylinder head(s) using new gaskets.
2. Assemble the rest of the valve tr ain (pushrods and rocker arms and/or
shafts).
ENGINE COVERS AND COMPONENTS
Install the timing cover(s) and oil pan. Re fer to your notes and drawings made
prior to disassembly and install all of the components that were removed. Install
the engine into the vehicle.
ENGINE START-UP AND BREAK-IN
STARTING THE ENGINE
Now that the engine is inst alled and every wire and hose is properly connected,
go back and double check that all cool ant and vacuum hoses are connected.
Check that you oil drain plug is instal led and properly tightened. If not already
done, install a new oil filt er onto the engine. Fill the crankcase with the proper
amount and grade of engine oil. Fill the cooling system with a 50/50 mixture of
coolant/water.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 513
1. Connect the vehicle battery.
2. Start the engine. Keep y
our eye on your oil pressure indicator; if it does
not indicate oil pressure within 10 se conds of starting, turn the vehicle
off.
WARNING - Damage to the engine can result if it is allowed to run with no oil
pressure. Check the engine oil level to make sure that it is full. Check for any
leaks and if found, repair the leaks be fore continuing. If there is still no
indication of oil pressure, y ou may need to prime the system.
3. Confirm that there are no fluid leaks (oil or other).
4. Allow the engine to reach nor mal operating temperature (the upper
radiator hose will be hot to the touch).
5. If necessary, set the ignition timing.
6. Install any remaining components such as the air cleaner (if removed for
ignition timing) or body panels which were removed.
BREAKING IT IN
Make the first miles on the new engine , easy ones. Vary the speed but do not
accelerate hard. Most importantly, do not lug the engine, and avoid sustained
high speeds until at least 100 miles. Ch eck the engine oil and coolant levels
frequently. Expect the engine to use a littl e oil until the rings seat. Change the
oil and filter at 500 miles, 1500 mile s, then every 3000 miles past that.
KEEP IT MAINTAINED
Now that you have just gone through all of that hard work, keep yourself from
doing it all over again by thoroughly maintaining it. Not that you may not have
maintained it before, heck you c ould have had one to two hundred thousand
miles on it before doing this. However, you may have bought the vehicle used,
and the previous owner did not keep up on maintenance. Which is why you just
went through all of that hard work. See?
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 549
Fig. 2: Negative backpressure EGR valve
DIGITAL EGR VALVE
The digital EGR valve, used on 3.1L (VIN T) engines, is designed to control the
flow of EGR independent of intake mani fold vacuum. The valve controls EGR
flow through 3 solenoid- opened orifices, which increa se in size, to produce 7
possible combinations. When a solenoid is energized, the armature with
attached shaft and swivel pintle, is lifted, opening the orifice.
The digital EGR valve is opened by t he ECM "quad-driver" (QDR), grounding
each solenoid circuit individually. The fl ow of EGR is regulated by the ECM
which uses information from the Coolant Temperature Sensor (CTS), Throttle
Position Sensor (TPS) and the Manifold Absolute Pressure (MAP) sensor to
determine the appropriate rate of flow for a particular engine operating
condition.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 573
7. Install the retaining bracket.
8. Connect the negative battery cable.
ELECTRONIC ENGINE CONTROLS
COMPUTER COMMAND CO NTROL (CCC) SYSTEM
The Computer Command Control (CCC) Sy stem is an electronically controlled
exhaust emission system that can m onitor and control a large number of
interrelated emission cont rol systems. It can monitor various engine/vehicle
operating conditions and then use this in formation to control multiple engine
related systems. The CCC syst em is thereby making constant adjustments to
maintain optimum vehicle performance und er all normal driving conditions while
at the same time allowing the catalyti c converter to effectively control the
emissions of HC, CO and NO
x.
OPERATION
The Electronic Control Module (ECM) is required to maintain the exhaust
emissions at acceptable le vels. The module is a sma ll, solid state computer
which receives signals from many source s and sensors; it uses these data to
make judgements about operating conditions and then control output signals to
the fuel and emission systems to ma tch the current requirements.
Inputs are received from m any sources to form a complete picture of engine
operating conditions. Some inputs are simp ly Yes or No messages, such as that
from the Park/Neutral switch; the vehicle is either in gear or in Park/Neutral;
there are no other choices. Other data is sent in quantitative input, such as
engine rpm or coolant temperature. T he ECM is pre-programmed to recognize
acceptable ranges or combinations of si gnals and control the outputs to control
emissions while providing good driv eability and economy. The ECM also
monitors some output circuits, making sure that the components function as
commanded. For proper engine oper ation, it is essential that all input and output
components function properly and comm unicate properly with the ECM.
Since the control module is programmed to recognize the presence and value
of electrical inputs, it will also note the lack of a signal or a radical change in
values. It will, for example, react to the loss of signal from the vehicle speed
sensor or note that engine coolant temperature has risen beyond acceptable
(programmed) limits. Once a fault is recognized, a numeric code is assigned
and held in memory. The SERVICE ENGIN E SOON Malfunction Indicator Lamp
(MIL), will illuminate to advise the operator that the system has detected a fault.
More than one code may be stored. Although not every engine uses every
code, possible codes range from 12-999. Additionally, the same code may carry
different meanings relative to each engine or engine family. For example, on the
3.3L (VIN N) engine, code 46 indicates a fault found in the power steering
pressure switch circuit. The same code on the 5.7L (VIN F) engine indicates a
fault in the VATS anti-theft system.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 580
4. Spray a commercial solvent onto the sensor threads and allow it to soak
in for at least five minutes.
5. Carefully remove the sensor wit h a special oxygen sensor socket.
To install: 6. First coat the new sensor's th reads with GM anti-seize compound No.
5613695 or the equivalent. This is not a conventional anti-seize paste.
The use of a regular compound may el ectrically insulate the sensor,
rendering it inoperative. Y ou must coat the threads with an electrically
conductive anti-seize compound. Installati on torque is 30 ft. lbs. (41 Nm).
Do not overtighten.
7. Reconnect the electric al wiring. Be careful not to damage the electrical
pigtail. Check the sensor boot fo r proper fit and installation.
8. Reconnect the negative battery cable.
COOLANT TEMPERATURE SENSOR
OPERATION
Most engine functions are affected by the coolant temperature. Determining
whether the engine is hot or cold is largely dependent on the temperature of the
coolant. An accurate temperature signal to the ECM is supplied by the coolant
temperature sensor. The coolant temperatur e sensor is a thermistor mounted in
the engine coolant stream. A thermistor is an electrical device that varies its
resistance in relation to changes in temperature. Low coolant temperature
produces a high resistance and high coolant temperature produces low
resistance. The ECM supplies a signal of 5 volts to the coolant temperature
sensor through a resistor in the ECM and measures the voltage. The voltage
will be high when the engine is cold and low when the engine is hot.
REMOVAL & INSTALLATION
1. Disconnect the negative battery cable.
2. Drain the cooling system to an appropr iate and clean container for reuse.
3. Disconnect the electrical wiring fr om the coolant temperature sensor.
4. Remove the coolant temperature sensor.
To install: 5. Install the coolant temperature sensor.
6. Connect the electrical wiring.
7. Fill the cooling system.
8. Connect the negative battery cable.
9. Start 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) 593
REMOVAL & INSTALLATION
1. Disconnect the negative battery cable.
2. Drain the engine coolant.
3. Raise and properly support the vehicle.
4. Disconnect the knock sensor wiring harness.
5. Remove the knock sensor from the engine block.
CAUTION - The knock sensor is mounted in the engine block cooling passage.
Engine coolant in the block will dr ain when the sensor is removed.
6. Installation is the reverse of remova l. Tighten the sensor to 14 ft. lbs (19
Nm).
VEHICLE SPEED SENSOR (VSS)
OPERATION
The VSS is located on the transmission and sends a pulsing voltage signal to
the ECM which is converted to miles per hour. This sensor mainly controls the
operation of the TCC system, shift light, cr uise control and activation of the EGR
system.
Fig. 1: Vehicle speed sensor (VSS)