Ignition Timing: Adjustments

1. Precondition the engine as follows:
a. Engine coolant temperature greater than 185° 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 Lead Connector Location:

3. Insert a paper clip into the idle speed connector (blue).

Tachometer Installed:

4. Connect a tachometer to the inserted clip.
NOTE: The tachometer should read at 1/3 of the actual engine speed. Multiply the reading by 3 to obtain the correct RPM.

Ignition Timing Adjustment Terminal Location:

5. With the ignition OFF, remove the waterproof plug from the connector (brown) for ignition timing adjustment and ground the terminal using a jumper wire.
6. Start the engine and allow it to run at curb idle speed.
7. Verify that Curb Idle Speed = 700 ± 100 rpm.

Ignition Timing Inspection:

8. Verify that Basic Ignition Timing is 5 ± 2 degrees BTDC.
9. If timing is not within specification, check the operation of the crankshaft position sensor and ignition control components. SEE Powertrain Management/Computers and Control Systems/Testing and Inspection/Procedures.
10. Stop the engine and disconnect the grounding jumper.