H. Adjust Idle Speed & Basic Timing & Test Feedback System

H. Adjust Idle Speed and Basic Timing Test Carburetor Feedback System

1. Start the engine and warm it to normal operating temperature.

2. Run the engine for at least five seconds between 2000 and 3000 RPM.





3. Using a tachometer, check the idle speed. If it is not between 650 - 850 RPM, readjust it to 750 RPM using idle speed adjusting screw No. 1 (SAS1) (Figure 12).

4. After the idle speed has been verified, adjust the basic ignition timing to 8~ BTDC using the Service Manual Procedure.

Note:
This is a new basic timing specification.

Recheck the idle speed and adjust if necessary.

5. Insert an exhaust gas analyzer probe into the tailpipe.

6. Run the engine at 2500 RPM in neutral for 30 seconds and then record the tailpipe CO reading at 2500 RPM.

7. If the CO reading is greater than 1.2%, re-check the installation of the jet mixture solenoid. Loosen the jet mixture solenoid and inspect it for misalignment, cross threading or over torque. Install it correctly by following the procedure covered in steps B-7 to B-10.

8. Run the engine at 2500 RPM in neutral for 30 seconds and then record the tailpipe CO reading at 2500 RPM.

9. If the CO reading is 1.2% or less move to step 10. If the CO reading is still greater than 1.2% then an Idle Speed & Mixture adjustment must be performed. Skip steps 10 through 12 and proceed to Section I.

10. Turn off the engine, disconnect the tachometer and remove the analyzer probe from the tailpipe.

11. Install the concealment plug into the hole to seal access to the idle mixture adjustment screw.

12. Reinstall the air cleaner assembly (manual transmission vehicles only).

13. Move to Section K.