Ignition Timing: Adjustments

1. Precondition the engine as follows:
a. Engine coolant temperature greater than 185 degrees F.
b. Lights, electric cooling fan, and all electrical accessories off.
c. Transmission in neutral or park.
d. Steering wheel in the neutral position.
2. Connect a timing light.

Tachometer Hook-up:

3. Insert a paper clip into the idle speed diagnostic connector and connect a tachometer to the inserted clip.

Ignition Timing Adjustment Connector Hook-up:

5. With the engine off ground the ignition timing adjustment terminal with a jumper lead.
6. Start the engine and allow it to run at curb idle speed.

Ignition Timing Inspection:

7. Using a timing light, check the ignition timing.

Basic Ignition Timing
5 +/- 2 degrees BTDC.

8. If necessary loosen the distributor mounting nut and adjust timing by rotating the distributor.
9. Stop the engine and disconnect the grounding jumper.
10. Start the engine and allow it to operate at curb idle speed.
11. Verify that thr ignition timing is as follows:

Actual Ignition Timing
15 degrees BTDC

NOTE Actual ignition timing may vary slightly under the direction of the ECU. If necessary re-check Basic Ignition Timing. If it is still correct no further action is required.