Idle Mixture
Idle Mixture Adjustment1. Remove the air cleaner.
2. Tag each of the vacuum hoses leading to the carburetor.
3. Disconnect the-harness connectors and the vacuum hoses at the carburetor.
4. Remove the carburetor.
5. Use a drill (1) to drill a hole in the seal plug (2) at the throttle chamber flange (3).
6. Use an appropriate tool to remove the seal plug.
7. Use compressed air to remove any shavings from the seal plug hole.
8. Remove the idle adjusting screw from the throttle chamber.
9. Inspect the idle adjusting screw.
If the adjusting screw head has been damaged by the drill, the screw must be replaced with a new one.
If the adjusting screw taper is excessively worn or stepped, the screw must be replaced with a new one.
10. Reinstall the idle adjusting screw to the throttle chamber.
11. Fully screw the idle adjusting screw into the throttle chamber.
Do not overtighten the screw.
12. Back off the idle adjusting screw 1 1/2 turns.
13. Reinstall the carburetor.
14. Reconnect the vacuum hoses and the harness connectors to the carburetor.
Pay close attention to the tags applied at removal.
Refer to "REMOVAL AND INSTALLATION" of the carburetor.
15. Reinstall the air cleaner.
16. Start the engine and allow it to idle until the cooling water reaches normal temperature.
17. Make sure that the choke valve is fully open. If the choke valve is not fully open, open it.
18. Make sure that the air conditioning system is off (if so equipped).
19. Move the front wheels to the straight ahead position (power steering equipped vehicle only).
20. Disconnect and plug the distributor line.
21. Disconnect and plug the canister purge line.
22. Disconnect and plug the Exhaust Gas Recirculation vacuum line.
23. Bend the attached rubber hose to close off the idle compensator vacuum line.
24. Use the throttle adjusting screw to adjust the idling .
Engine Idling Speed rpm 900
25. Use a dwell or duty meter to measure the dwell or duty.
Connect the positive side of the meter to the monitor lead (1) and the negative side of the meter to ground.
After confirming dwell or duty to vary, adjust setting of idle adjusting screw (2) to obtain an average dwell or duty as specified.
Dwell or Duty
The dwell or duty reading specified is the average of the most constant vibration.
26. Use the throttle adjusting screw to reset the engine idling speed.
Engine Idling Speed rpm 900
27. Remove the air cleaner.
28. Replace the idle adjusting screw plug.
Tap the new plug in until it is flush with the carburetor surface.
29. Reinstall the air cleaner.