Ignition Timing: Adjustments

NOTE:
Check curb idle speed before proceeding with the following procedures. If curb idle speed is not within range on under hood emissions label, diagnose and repair problem before proceeding.

PROCEDURE:

1. Place transmission in neutral and turn off all lights and accessories.
2. Connect timing light to number 1 cylinder. Refer to timing light manufacturer's instructions for proper connecting procedures.
3. Start engine and allow to reach normal operating temperature.

Coolant Temperature Sensor:

4. Disconnect coolant temperature sensor electrical connector. The CHECK ENGINE lamp on the instrument panel should illuminate once this sensor has been disconnected.

Distributor Hold-Down:

Timing Scale and Magnetic Timing Probe Receptacle:

5. Check timing by pointing timing light at the front crankshaft pulley. If timing is within 2° of specifications do not adjust. Timing specifications can be found on the under hood emissions label. If under hood emissions label is not readable, or is missing, locate specification elsewhere.

^ If timing is incorrect, loosen distributor hold-down bolt and rotate distributor housing until correct timing specification is obtained.

NOTE: There is an additional socket next to the timing scale, for a magnetic timing probe. Do not set the timing through this socket with a standard timing light. This socket is positioned 10 degrees ATDC and will yield inaccurate timing specifications if used with a standard timing light.

6. Tighten distributor hold-down bolt, and recheck timing. Connect coolant temperature sensor electrical connector, and erase any fault codes that may have been set.
7. Recheck idle rpm.