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GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 689
c. Foreign material in jets
3. Remove throttle side metering rod. Install mixture control solenoid
gauging tool, J-33815-1, BT-8253-A, or equi valent, over the throttle side
metering jet rod guide and temporarily reinstall the solenoid plunger into
the solenoid body.
4. Holding the solenoid plunger in the DOWN position, use tool J-28696-10,
BT-7928, or equivalent, to turn lean mixture solenoid screw
counterclockwise until the plunger br eaks contact with the gauging tool.
Turn slowly clockwise until the pl unger makes contact with the gauging
tool. The adjustment is correct when t he solenoid plunger is contacting
both the solenoid stop and the gauging tool.
If the total difference in adjustment required less than
3/4 turn of the lean mixture
solenoid screw, the original setting was within the manufacturer's specifications.
5. Remove solenoid plunger and gaugi ng tool and reinstall metering rod
and plastic filler block.
6. Invert air horn and remove rich mixt ure stop screw from bottom side of
air horn, using tool J-28696-4, BT-7967-A, or equivalent.
7. Remove lean mixture screw plug and the rich mixture stop screw plug
from air horn, using a punch.
8. Reinstall rich mixtur e stop screw in air horn and bottom lightly, then back
screw out
1/4 turn.
9. Reinstall air horn gasket, mixture c ontrol solenoid plunger and air horn to
carburetor.
10. Adjust the M/C solenoid pl unger travel as follows:
a. Insert float gauge down D- shaped vent hole. Press down on
gauge and release, observing th at the gauge moves freely and
does not bind. With gauge released, (plunger UP position), read at
eye level and record the reading of the gauge mark (in
inches/millimeters) that lines up with the top of air horn casting,
(upper edge).
b. Lightly press dow n on gauge until bottomed, (plunger DOWN
position). Read and record (in inc hes/millimeters) the reading of
the gauge mark that lines up with top of air horn casting.
c. Subtract gauge UP position from the gauge DOWN position and
record the difference. This difference is the total plunger travel.
Insert external float gauge in vent hole and, with tool J-28696-10,
BT-7928, or equivalent, adjust rich mixture stop screw to obtain
5/32 in. (3.9mm) total plunger travel.
11. With solenoid plunger travel corre ctly set, install plugs (supplied in
service kits) in the air horn, as follows:
a. Install plug, hollow end down, into the access hole for the lean
mixture (solenoid) screw. Use suit ably sized punch to drive plug
into the air horn until t he top of plug is even with the lower. Plug
must be installed to retain the sc rew setting and to prevent fuel
vapor loss.
Page 690 of 875
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 690
b. Install plug, with hollow end do
wn, over the rich mixture stop
screw access hole and drive plug into place so that the top of the
plug is
3/16 in. (4.7mm) below the surface of the air horn casting.
Plug must be installed to retain screw setting.
12. To check the M/C solenoid dwell, first disconnect vacuum line to the
canister purge valve and plug it. Ground diagnostic TEST terminal and
run engine until it is at normal operat ion temperature (upper radiator
hose hot) and in closed loop.
13. Check M/C dwell at 3000 rpm. If within 10-50 degrees, calibration is
complete. If higher than 50 degrees, chec k the carburetor for a cause of
rich condition. If below 10 degrees, look for a cause of lean engine
condition such as vacuum leaks. If none are found, check for the cause
of a lean carburetor.
Fig. 22: Installing the mixture control solenoid gauging tool
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GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 691
Fig. 23: Adjusting the l ean mixture solenoid screw
Fig. 24: Adjusting the rich mixture stop screw
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GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 692
IDLE AIR VALVE
A cover is in place over t
he idle air bleed valve. Also , the access holes to the
idle mixture needles are s ealed with hardened plugs. This is done to seal the
factory settings, during original equipment production. These items are NOT to
be removed unless required for cleaning, part replacement, improper dwell
readings or if the System Performance Check indicates the carburetor is the
cause of the trouble.
ROCHESTER E4ME AND E4MC
1. With engine OFF, cover the internal bowl vents and inlet to bleed valve
and the carburetor air intakes with maski ng tape. This is done to prevent
metal chips from entering.
2. Carefully drill rivet head of idle air bleed cover, with 0.110 in. (2.8mm) drill bit.
3. Remove rivet head and all pieces of rivet.
4. Lift cover off air bleed valve and bl ow out any metal shavings, or use a
magnet to remove excess metal.
CAUTION - Always wear eye protection when using compressed air.
5. Remove masking tape.
6. Start engine and allow it to reac h normal operating temperature.
7. Disconnect the vacuum hose from t he canister purge valve and plug it.
8. While idling in D for automatic transmission or N for manual
transmission, slowly turn the valve c ounterclockwise or clockwise, until
the dwell reading varies within the 25-35 degree range, attempting to be
as close to 30 degrees as possible.
Perform this step carefully. The air bleed valve is very sensitive and should be
turned in
1/8 turn increments only.
9. If the dwell reading d oes not vary and is not within the 25-35 degree
range, it will be necessary to remove the plugs and to adjust the idle
mixture needles.
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GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 693
Fig. 25: Installing the idle air bleed valve gauging tool
Fig. 26: Adjusting the idle air bleed valve
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GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 694
IDLE MIXTURE
E2SE CARBURETORS
1. Remove the carburet or from the engine.
2. Remove the plugs coveri ng the idle mixture needles.
3. Turn the mixture needle in until slight ly seated, then back it out 4 turns.
4. If the plug in the air horn coveri ng the idle air bleed has been removed,
replace the air horn. If the plug is still in place, do not remove it.
5. Remove the vent stack screen a ssembly to gain access to the lean
mixture screw.
6. Using tool J-28696-10 or equivalent, turn the lean mixture screw in until
lightly seated, then back out 2
1/2 turns.
7. Install the carburetor on the engine.
8. Disconnect the bowl vent line at the carburetor.
9. Disconnect the EGR hos e and canister purge hose at the carburetor.
Cap the ports on t he carburetor.
10. Find the hose from port D of the carburetor to the temperature sensor
and secondary vacuum break thermal vacuum switch. Disconnect and
plug the vacuum hose going to the air cleaner.
11. Connect the positive lead of a dwell me ter to the mixture control solenoid
test lead (green connector). Connect the other lead to ground. Set the
meter to the 6 cylinder position.
12. Run the engine on the high step of the fast idle cam until the cooling fan
starts to cycle.
13. Run the engine at 3,0 00 rpm and adjust the lean mixture screw slowly.
Allow the reading to stabilize, obtain an average dwell of 35 degrees. It is
normal for the dwell to vary in a narrow range.
14. Return to idle.
15. Adjust the idle mixt ure screw to obtain an av erage dwell of 25 degrees.
Allow time for the reading to stabilize.
16. Run the engine at 3,000 rpm and not e the dwell reading. It should be
varying with an average reading of 35 degrees. If it does not, repeat the
earlier steps.
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GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 695
Fig. 27: Idle mixture needle plug removal
E4ME CARBURETORS (ELECTRIC CHOKE) 1. Using tool J-29030, BT-7610-B, or equivalent, turn both idle mixture
needles clockwise until they are lightly seated, then turn each mixture
needle counterclockwise 3 turns.
2. Reinstall carburetor on engine using a new flange mounting gasket, but
do not install air cleaner and gasket at this time.
3. Disconnect the vacuum hose to canister purge valve and plug it.
Readjust the idle air bleed valve to finalize correct dwell reading.
4. Connect the positive lead of a dwell me ter to the mixture control solenoid
test lead (green connector). Connect the other lead to ground. Set the
meter to the 6 cylinder position.
5. Start engine and run unt il fully warm, then repeat the idle air bleed valve
adjustment.
6. If unable to set dwell to 25-35 degrees and the dwell is below 25
degrees, turn both mixture needles counter clockwise an additional turn. If
dwell is above 35 degrees, turn both mixture needles clockwise an
additional turn. Readjust idle air bleed valve to obtain dwell limits. Repeat
as needed.
7. After adjustments are complete, seal the idle mixture needle openings in
the throttle body, using silicone sealant, RTV rubber, or equivalent. The
sealer is required to discourage unnecessary adjus tment of the setting
and to prevent fuel vapor loss in that area. Reconnect canister vacuum
hose.
8. On vehicles without an Idle Load Co mpensator (ILC), adjust curb idle
speed if necessary.
9. Check, and if necessary, adjust fa st idle speed as described on Vehicle
Emission Control Information (VECI) label.
Page 696 of 875

GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 696
Fig. 28: Lean mixture and idle mixture screw adjustment
E4MC CARBURETOR (HOT AIR CHOKE) 1. Using tool J-29030-B, BT-7610-B, or equivalent, turn each idle mixture
needle clockwise until lightly seated, then turn each mixture needle
counterclockwise 3 turns.
2. Reinstall carburetor on engine, using a new flange mounting gasket, but
do not install air cleaner or gasket at this time.
3. Disconnect vacuum hose to c anister purge valve and plug it.
4. Connect the positive lead of a dwell me ter to the mixture control solenoid
test lead (green connector). Connect the other lead to ground. Set the
meter to the 6 cylinder position.
5. Start engine and allow it to reac h normal operating temperature.
6. While idling in D ( N for manual transmission), adjust both mixture
needles equally, in
1/8 turn increments, until dwell reading varies within
the 25-35 degree range, attempting to be as close to 30 degrees as
possible.
7. If reading is too low, turn mixtur e needles counterclockwise. If reading is
too high, turn mixture needl es clockwise. Allow time for dwell reading to
stabilize after each adjustment.
After adjustments are complete, seal t he idle mixture needle openings in the
throttle body, using silicone sealant, RTV rubber, or equivalent. The sealer is
required to discourage unnece ssary readjustment of the setting and prevent fuel
vapor loss in that area.
8. On vehicles without a carburetor -mounted Idle Load Compensator (ILC) ,
adjust curb idle speed if necessary.