Ignition Timing: Adjustments

Warning: Be sure to apply parking brake and/or block wheels before performing any test with the engine running.

PURPOSE: Proper ignition timing is required to obtain optimum engine performance. The distributor must be correctly indexed to provide correct initial ignition timing.

Note: Check curb idle speed before proceeding to the following procedures. If the idle speed is not within specifications, diagnose and repair before proceeding.

1. Place transmission in neutral and turn off all lights and accessories.

2. if using a magnetic timing light, insert the pickup probe into the open receptacle next to the timing scale window. if a magnetic timing unit is not available, use a conventional timing light connected to the number one cylinder spark plug cable.

Caution: Do not puncture cables, boots or nipples with test probes. Always use proper adapters. Puncturing the spark plug cables with a probe will damage the cables. The probe can separate the conductor and cause high resistance. In addition breaking the rubber insulation may permit secondary current to arc to ground.

Coolant Temperature Sensor:

3. Start engine and allow to warm up to normal operating temperature.
4. Disconnect coolant temperature sensor electrical connector on thermostat housing. The CHECK Engine lamp on the instrument panel should illuminate once this sensor has been disconnected, and the cooling fan will come on and stay on throughout the procedure.

Distributor Hold-Down:

Timing Scale Above Crank Pulley--Viewed From Front Of Car:

Note: Many driveablity problems can be caused by a slipped timing belt, always check cam timing when adjusting timing on this vehicle.


5. Check timing through timing window in transaxle bellhousing. If timing is within 2° of specifications do not adjust. If timing is incorrect, loosen distributor hold-down bolt and rotate distributor housing until correct timing specification is obtained.
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.

Note: There is an additional socket in the bellhousing of the transaxle, for a magnetic timing probe. Do not set the timing through this socket using a standard timing light, as this socket is positioned 10° ATDC and will yield inaccurate timing.