S15/T15 Jimmy 2WD L4-119 1.9L VIN A 2-BBL (1983)
Air/Fuel Mixture: Adjustments
California
IDLE MIXTURE ADJUSTMENT
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Set parking brake and block drive wheels.
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Place transmission in neutral.
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Remove carburetor assembly.
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Remove idle mixture screw plug using a screw driver inserted into the slit on carburetor lower flange.
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Reinstall carburetor assembly.
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Make idle speed and mixture adjustment with the following conditions:
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Engine at normal operating temperature.
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Choke open.
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A/C off.
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Vacuum lines for distributor, idle compensator and EGR valve disconnected and plugged.
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Idle compensator hose closed by bending hose.
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Connect dwell meter (4-Cyl. scale) or duty meter to dwell meter lead.
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Turn the idle mixture adjust screw all the way in and back out 1 1/2 turns.
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Adjust throttle adjust screw to 850-900 rpm.
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After confirming dwell or duty to vary, adjust idle mixture adjusting screw to obtain an average of 36° or 40%.
NOTE: While idling, it is normal for the dwell or duty to increase and decrease fair constantly over a relatively narrow range (9° or 10%).
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Reset throttle adjust screw to 850-950 rpm
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If A/C is installed:
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Turn A/C on "Max COLD" and set blower to high.
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Open the throttle to approximately 1/3 and allow the throttle to close. This allows the speed up solenoid to reach full travel.
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Adjust the speed up controller adjusting screw to set idle at 900 rpm.
