Ignition Timing: Adjustments

1. Warm the engine to the normal operating temperature.
2. Rev the engine to 2000-3000 RPM two or three times and allow the engine to return to idle.
3. Turn off all electrical loads.

NOTE: If the Rotunda New Generation STAR (NGS) Tester is NOT being used, ensure that the Idle Air Control (IAC) solenoid is disconnected.

4. Check the idle speed. Idle speed should be 750 ± 50 RPM.
5. Connect a Rotunda Inductive Timing Light (or equivalent) to the distributor No.1 spark plug wire and to the battery terminals.
6. Ensure that the timing indicator is pointing to the 15° Before Top Dead Center (BTDC) mark on the crankshaft pulley.
- Each notch on the crankshaft pulley represents 5 degrees.





7. If the marks are not aligned, loosen the distributor bolt and turn the distributor to make the adjustment.
- Ignition Timing is 15°± 2° BTDC.
8. Reconnect the IAC solenoid if previously disconnected.