GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 652
6. Connect the negative battery cable.
MODULE
It is not necessary to remove t he distributor from the vehicle.
1. Disconnect the negative battery cable.
2. Remove the distributor cap, rotor and pickup coil.
3. Remove the 2 module attaching screws and lift the module up. Remove
the leads from the module, observi ng the colors on each lead. These
leads can not be interchanged.
If the module is to be reused, do not wi pe the grease from the module or the
distributor base. If a new module is to be installed, a package of silicone grease
will be included with it. Spr ead the grease on the metal face of the module and
on the distributor base wher e the module seats. This grease is necessary for
module cooling.
To install: 4. Install the module, tighten the reta ining screws and connect the wiring.
5. Install the distributor rotor and distributor cap.
6. Connect the negative battery cable.
Fig. 7: Ignition coil module mounting - always coat the base with silicone
dielectric grease.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 653
PICKUP COIL
Fig. 8: Pickup coil and related component s - distributor with external coil
1. Disconnect the negative battery cable.
2. Remove the distributor cap and then the rotor.
3. Remove 3 screws from the magnetic shield. Remove the magnetic shield
and C-washer. Remove the magnet, pole piece and pickup coil.
4. Installation is the revers e of the removal procedure.
IGNITION TIMING DESCRIPTION
Ignition timing is the measurement, in de grees of crankshaft rotation, of the
point at which the spark plugs fire in eac h of the cylinders. It is measured in
degrees before or after Top Dead Center (TDC) of the compression stroke.
Because it takes a fraction of a second for the spark plug to ignite the mixture in
the cylinder, the spark plug must fire a little before the piston reaches TDC.
Otherwise, the mixture will not be complete ly ignited as the piston passes TDC
and the full power of the explosion will not be used by the engine.
The timing measurement is given in degr ees of crankshaft rotation before the
piston reaches TDC (BTDC). If the setting fo r the ignition timing is 5° BTDC, the
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 654
spark plug must fire 5° before each pist
on reaches TDC. This only holds true,
however, when the engine is at idle speed.
As the engine speed increases, the pist ons go faster. The spark plugs have to
ignite the fuel even sooner if it is to be completely ignited when the piston
reaches TDC.
If the ignition is set too far advanced (B TDC), the ignition and expansion of the
fuel in the cylinder will occu r too soon and try to force the piston down while it is
still traveling up. This causes engine ping. If the ignition spark is set too far
retarded, after TDC (ATDC), the pi ston will have already passed TDC and
started on its way down when the fuel is igni ted. This will cause the piston to be
forced down for only a portion of its trav el, resulting in poor engine performance
and lack of power.
When timing the engine, the Number 1 pl ug wire should be used to trigger the
timing light. On engines where timing is adjustable, the notch for the No. 1
cylinder is usually scribed across all th ree edges of the double sheaf pulley.
Another notch located 180° away from t he No. 1 cylinder notch is scribed only
across the center section of the pulley to make it distinguishable from the No. 1
cylinder notch.
There are two basic types of timing light s available. The first type of light
operates from the car's battery. Two al ligator clips connect to the battery
terminals, while a third wire connects to the spark plug with an adapter or to the
spark plug wire with an inductive pickup. This type of light is more expensive,
but the xenon bulb provides a nice bright flash which can even be seen in
sunlight. The second type replaces the battery source with 110-volt house
current. Some timing lights have other func tions built into them, such as dwell
meters, tachometers, or re mote starting switches. These are convenient, in that
they reduce the tangle of wires under t he hood, but may duplicate the functions
of tools you already have.
Because this car uses electronic ignition, you should use a timing light with an
inductive pickup. This pickup simply cl amps around the Number 1 spark plug
wire (in this case, the coil wire), elimin ating the adapter. It is not susceptible to
crossfiring or false triggering, which ma y occur with a conventional light due to
the greater voltages produc ed by these systems.
ADJUSTMENT
When adjusting the timing, refer to the instructions on the emission control
sticker inside the engine compartment. If th e instructions on the label disagree
with the procedure listed below, follo w the instructions on the label.
1982-87 VEHICLES 1. Locate the timing marks on the cran kshaft pulley and the front of the
engine.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 656
8. Once the timing is set to specific
ation, tighten the distributor hold-down
clamp. Recheck the timing to make su re it did not change while the bolt
was being tightened.
9. Remove the jumper wire from the ALDL connector, if applicable, with the
engine still running. (Usually, if this is performed before the engine is
shut off, no trouble codes will be stored.)
10. Turn the engine OFF, then remove the timing light and tachometer.
Reconnect the number 1 spark plug wire, if disconnected.
11. Attach the 4-wire EST connector at the distributor, or reconnect the Set
Timing connector, if applicable.
12. Check for fault code 42, and clear, if necessary, by disconnecting the
negative battery cable for at least 30 seconds.
To prevent ECM damage, the key must be in the OFF position when
disconnecting or reconnecting battery cables.
1988-90 VEHICLES
When adjusting the timing, refer to the instructions on the emission control
sticker inside the engine compartment. If th e instructions on the label disagree
with the procedure listed below, follo w the instructions on the label.
1. Locate the timing marks on the cran kshaft pulley and the front of the
engine.
2. Clean off the marks and coat them with white paint or chalk, so that they
may be easily seen.
3. Run the engine until it reaches no rmal operating temperature, then shut
off the engine.
4. With the ignition OFF, connect a ta chometer to the distributor, and a
timing light with an inductive pickup lead to the No. 1 spark plug wire.
WARNING - Never pierce a secondary ignition wire in order to connect a timing
light. A pierced wire may lead to engine misfiring and driveability problems.
5. Start the engine. With the engine running and all accessories off, use a
jumper wire to connect diagnostic terminal B and ground terminal A of
the 12-terminal Assembly Line Diagnostic Link (ALDL), located under the
instrument panel.
If jumping the ALDL terminals does not prevent timing advance, the EST
bypass wire will have to be disconnected instead.
6. Aim the timing light at the timing mark. The line on the balancer or pulley
will line up with the timing mark. If a change in timing is necessary,
loosen the hold-down clamp bolt at t he base of the distributor. While
observing the timing mark, rotate the distributor slightly until the line
indicates the correct timing. Use t he timing specification on the emission
control label in the engine compartm ent. If this label is missing or
damaged, refer to the Tune- Up Specifications chart in this Section.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 658
Connect the timing light power leads
according to the manufacturer's
instructions.
WARNING - Never pierce a secondary ignition wire in order to connect a timing
light. A pierced wire may lead to engine misfiring and driveability problems.
5. Start the engine. With the engine running at normal operating
temperature and all accessories OFF, disconnect the EST bypass
connector.
An ECM code will be set when the EST bypass connector is disconnected.
6. Aim the timing light at the timing mark. The line on the balancer or pulley
will line up with the timing mark. If a change in timing is necessary,
loosen the hold-down clamp bolt at t he base of the distributor. While
observing the timing mark, rotate the distributor slightly until the line
indicates the correct timing. Use t he timing specification on the emission
control label in the engine compartm ent. If this label is missing or
damaged, refer to the Tune- Up Specifications chart in this Section.
7. Tighten the distributor hold-down bolt and recheck the ignition timing to
make sure the distributor was not moved when the bolt was tightened.
8. Turn the engine OFF and remove the timing light and tachometer.
Reconnect the number 1 spark plug wire, if disconnected.
9. Connect the EST bypass connector , then check for and clear the ECM
code by disconnecting the negative battery cable for at least 30 seconds.
To prevent ECM damage, the key must be in the OFF position when
disconnecting or reconnecting battery cables.
Fig. 2: EST bypass connector
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 707
Fig. 43: The adjustment specifications on the emission control information label
must always be followed
ROCHESTER E4ME AND E4MC 1. Disconnect the battery and remove the air cleaner.
2. Disconnect the accelerator linkage.
3. Disconnect the transmission detent cable.
4. If equipped, remove the cr uise control cable.
5. Tag and detach all of the necessa ry vacuum lines and electrical
connections.
6. Disconnect the fuel line at the carburetor inlet.
7. Remove the attaching bolts and remove the carburetor.
To install: 8. Position the carburetor onto the manifold and install the attaching bolts.
9. Connect the fuel line at the carburetor inlet.
10. Attach all of the vacuum lines and electrical connections, as tagged
during removal.
11. If equipped, install the cruise control.
12. Connect the transmission detent cable.
13. Connect the accelerator linkage.
14. Install the air cleaner and connect the battery.
OVERHAUL
Carburetor overhaul kits are reco mmended for each overhaul. These kits
contain all gaskets and new parts to re place those which deteriorate most
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 711
THROTTLE BODY INJECTION SYSTEM
SYSTEM DESCRIPTION
The throttle body injection (TBI) system used on 2.5L (VIN 2) and 5.0L (VIN E)
engines is centrally located
on the intake manifold. Its function is to supply the
correct air/fuel mixture to the engine, as directed by the Engine Control Module
(ECM).
The TBI unit consists of two relatively simple casting assemblies: a throttle body
and a fuel metering assembly. Components include, a pressure regulator, idle
air control valve, fuel injector(s), thro ttle position sensor, fuel inlet and a fuel
return fitting.
The Throttle Body Injection identifi cation number is stamped on the lower
mounting flange located near the TPS. Th e number is in alphabetical code and
should be noted before servicing the unit.
An oxygen sensor in the exhaust syst em functions to provide feedback
information to the ECM as to oxygen content in the exhaust. The ECM then
uses this information to modify fuel de livery to achieve as near as possible an
ideal air/fuel ratio of 14.7 :1. This ratio permits the ca talytic converter to become
more effective in reducing emissions wh ile providing acceptable driveability.
Should you encounter any type of engine performance problem, have a
complete CCC system test performed by a qualified, professional technician. If
the fault lies in the injection system, you can use the following procedures to
remove the TBI unit and replace the defective component(s).
RELIEVING FUEL SYSTEM PRESSURE
1. Disconnect the negative battery cable to prevent fuel discharge if the key
is accidentally turned to the RUN position.
2. Loosen the fuel filler cap to relieve fuel tank pressure and do not tighten
until service has been completed.
3. Fuel system pressure is automatic ally relieved when the engine is turned
OFF. No further action is necessary.
When disconnecting fuel lines, there ma y still be a small amount of fuel
released. Cover the fuel line connection wi th a shop cloth to collect the fuel,
then place the cloth in an approved container.
ELECTRIC FUEL PUMP
REMOVAL & INSTALLATION
The fuel pump is part of t he fuel sender assembly located inside the fuel tank.
1. Release the fuel syst em pressure and disconnec t the negative battery
cable.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 712
2. Drain the fuel tank, then raise
and safely support the vehicle.
3. Remove the fuel tank from the vehicle.
4. Clean the area surrounding t he sender assembly to prevent
contamination of the fuel system.
5. Remove the fuel sender fr om the tank as follows:
a. Use tool J-24187 or equivalent to remove the sending unit
retaining cam. Remove the fuel sender and O-rings from the tank.
Discard the O-rings.
6. If necessary, separate the fuel pum p from the sending unit assembly.
To install: 7. If removed, install the fuel pump to the sending unit. If the strainer was
removed, it must be re placed with a new one.
8. Inspect and clean the O-ring mating surfaces.
9. Install a new O-ring in the groove around the tank opening. If applicable,
install a new O-ring on t he fuel sender feed tube.
10. Install the fuel sender assembly as follows: a. The fuel pump strainer must be in a horizontal position, and when
installed, must not block the travel of the float arm. Gently fold the
strainer over itself an d slowly position the sending assembly in the
tank so the strainer is not dam aged or trapped by the sump walls.
11. Install the retaining cam us ing tool J-24187 or equivalent.
12. Install the fuel tank assembly.
13. Lower the vehicle.
14. Fill the fuel tank, tighten the f uel filler cap and connect the negative
battery cable.
Fig. 1: Fuel pump and sending unit assembly