1982 CHEVROLET CAMARO fuel pump

GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 709
passages, or air bleeds. Clean all jets and va
lves separately to avoid accidental
interchange.
Check all parts for wear or damage. If we ar or damage is found, replace the
defective parts. Especially check the following:
1. Check the float needle and seat for wear.
2. Check the float hinge pin for wear and the float(s) for dents or distortion.
Replace the float if fuel has leaked into it.
3. Check the throttle and choke sha ft bores for wear or an out-of-round
condition. Damage or wear to the thro ttle arm, shaft, or shaft bore will
often require replacement of the throttle body. These parts require a
close tolerance of fit; wear may allow air leakage, which could affect
starting and idling.
Throttle shafts and bushings are not included in overhaul kits. They can be
purchased separately or repaired by a qualified carburetor overhaul shop.
4. Inspect the idle mixt ure adjusting needles for bu rrs or grooves. Any such
condition requires replacement of t he needle, since you will not be able
to obtain a satisfactory idle.
5. Test the accelerator pump check va lves. They should pass air one way
but not the other. Test for proper s eating by blowing and sucking on the
valve. Replace the valve check ball and spring as necessary. If the valve
is satisfactory, wash the valve part s again to remove breath moisture.
6. Check the bowl cover for war ped surfaces with a straightedge.
7. Closely inspect the accelerato r pump plunger for wear and damage,
replacing as necessary.
8. After the carburetor is assembled, check the choke valve for freedom of
operation.
9. Check, repair or replace parts, if the following problems are encountered:
FLOODING
• Inspect the float valve and seat for dirt, deep wear grooves, scores and
improper sealing
• Inspect the float valve pull clip for proper installation; be careful no\
t to
bend the pull clip
• Inspect the float, the float arms and the hinge pin for distortion, binds,
and burrs. Check the density of the mate rial in the float; if heavier than
normal, replace the float
• Clean or replace the fuel inlet f ilter and check the valve assembly
HESITATION
• Inspect the pump plunger for cracks, scores or cup excessive wear. A
used pump cup will shrink w hen dry. If dried out, soak in fuel for 8 hours
before testing
• Inspect the pump duration and return springs for weakness or distortion \

GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 710
•

Check the pump passages and the jet(s) for dirt, improper seating of the
discharge checkball or t he temperature bypass disc and/or scores in the
pumpwell. Check the condition of t he pump discharge check ball spring,
replace as necessary
• Check the pump linkage for excessiv e wear; repair or replace as
necessary
HARD STARTING-POOR COLD OPERATION
• Check the choke valve and linkage for excessive wear, binds or
distortion
• Test the vacuum break diaphragm(s) for leaks
• Clean or replace the fuel filter
• Inspect the float valve fo r sticking, dirt, etc.
• Also check the items under "Flooding"
POOR PERFORMANCE-POOR GAS MILEAGE
• Clean all fuel and vacuum passages in the castings
• Check the choke valve fo r freedom of movement
• Check the Mixture Control (M/C) soleno id for sticking, binding or leaking
• Check the air valve and secondary me tering rod for binding conditions. If
the air valve or metering rod is da maged or the metering rod adjustment
is changed from the factory setting, the air horn assembly must be
replaced. Also check the air valve le ver spring for proper installation
ROUGH IDLE
• Inspect the gasket and gasket mating su rfaces on the casting for nicks,
burrs or damage to the sealing beads
• Check the operation and sealing of the mixture control solenoid
• Clean all of the idle field passages
• If removed, inspect the idle mixture needle for ridges, burrs or being bent
• Check the throttle lever and valves for binds, nicks. or other damage
• Check all of the diaphragms for possible ruptures or leaks
After cleaning and checking all components, reassemble the carburetor, using
new parts and referring to the exploded view. When reassembling, make sure
that all screws and jets are tight in their seats, but do not overtighten as the tips
will be distorted. Tighten al l screws gradually, in rotation. Do not tighten needle
valves into their seats; uneven jetting will result. Always use new gaskets. Be
sure to follow all assembly and adjustment procedures.
Before performing any service on the carburet or, it is essential that it be placed
on a suitable holding fixtur e, such as tool J-9789-118, BY-30-15 or equivalent.
Without the use of the holding fixture, it is possible to damage throttle valves or
other parts of the carburetor.

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

GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 713

Fig. 2: Fuel pump locking cam tool
TESTING 1. Turn the engine OFF and relieve the fuel pressure.
2. Remove the air cleaner and plug the THERMAC vacuum port on TBI.
3. Install a fuel pressure gauge between the throttle body unit and the fuel line. Use a back-up wrench to hold fuel nut on the TBI when removing
the fuel line.

Fig. 3: Fuel pressure can be check ed using an inexpensive pressure/vacuum
gauge

GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 726
RELIEVING FUEL SYSTEM PRESSURE
1. Remove the fuse marked "Fuel Pu mp" from the fuse block in the
passenger compartment.
2. Crank the engine. Th e engine will start and run until the fuel supply
remaining in the lines is exhauste d. When the engines stops, engage the
starter again for three seconds to a ssure dissipation of any remaining
pressure.
3. With the ignition OFF, disconnect the negative battery cable to prevent
fuel discharge if the key is accidentally turned to the ON position.
Replace the fuse with the ignition OFF.
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 removal and installation procedures fo r the Crossfire injection system fuel
pump is identical to the Throttle Body In jection (TBI) system. Please refer to the
TBI fuel pump procedures earlier in this repair guide.
TESTING
The testing procedures for the Crossfire in jection system fuel pump is identical
to the Throttle Body Injection (TBI) syst em. Please refer to the TBI fuel pump
procedures earlier in this repair guide.
THROTTLE BODY
REMOVAL & INSTALLATION
FRONT UNIT
1. Relieve the fuel system pressure.
2. Remove the air cleaner assembly, noting the connection points of the
vacuum lines.
3. Detach the electrical connectors at the injector and the idle air control
motor.
4. Disconnect the vacuum lines from the TBI unit, noting the connection
points. During installation, refer to the underhood emission control
information decal for vacuum line routing information.
5. Disconnect the transmission det ent cable from the TBI unit.
6. Disconnect the fuel inlet (feed) and fuel balance line connections at the
front TBI unit.
7. Remove and discard the throttle cont rol rod retaining clip from the front
TBI throttle lever stud. A new clip must be used during reassembly.
8. Unbolt and remove the TBI unit.

GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 736
The mass air flow systems measure the
mass of air that is drawn into the
engine cylinders, rather than just the vo lume. The sensor contains a hot-wire
sensing unit, which is made up of an electronic balanced bridge network.
Whenever current is suppli ed to the sensor, the bridge is energized and the
sensing hot-wire is heated. As the air enter s the mass air flow sensor, it passes
over and cools the hot wire. When the hot wire is cooled, it's resistance changes
and additional current is needed to k eep the bridge network balanced. This
increase in current is sent to the computer as a voltage signal and is used to
calculate the mass of the incoming air. The ECM uses this information to\

determine the duration of fuel injection pulse, ignition timing and EGR operation.
The speed density systems calculate the volume of air moving through the
intake. The ECM establishes the speed fact or through a signal from the ignition
module. The Manifold or Intake Air Temperature (MAT/IAT) and the Engine
Coolant Temperature (ECT) sensors work together to assure that proper
temperature information gets to the ECM wh ile the Manifold Absolute Pressure
(MAP) sensor monitors the changes in m anifold pressure which results from
changes in engine loading. These three se nsors contribute to the density factor.
Together, these inputs (engine speed, coolant temperature sensor, etc ...) are
the major determinants of the air/fuel mixture delivered by the fuel injection
system.
The following engines and fuel managem ent systems are covered in this
section:
• 1985-1989 2.8L MPFI - Mass Air Flow
• 1990-1992 3.1L MPFI - Speed Density
• 1985-1989 5.0L and 5.7L TPI - Mass Air Flow
• 1990-1992 5.0L and 5.7L TPI - Speed Density
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 reliev e the tank pressure and do not tighten
until service has been completed.
3. Connect J-34730-1 fuel pressure gauge or equivalent, to the fuel
pressure test valve. Wrap a shop towel around the fitting while
connecting the gauge to prevent spillage.
4. Place the end of the bleed hose into a suitable container and open the
valve to relieve the fuel system pressure.
ELECTRIC FUEL PUMP
REMOVAL & INSTALLATION
The fuel pump is part of t he fuel sender assembly located inside the fuel tank.

GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 737
1. Release the fuel syst
em pressure and disconnec t the negative battery
cable.
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. Using tool J-24187 or equivalent, re move the sending unit retaining cam.
Remove the fuel sender and O-rings fr om the tank. Discard the O-rings.

Fig. 1: A special tool is usually availa ble to remove or install the fuel pump
locking cam
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.