How to Set an Engine Timing on a 1989 Ford Mustang

The 1989 Mustang uses a Ford EEC IV ignition system with a distributor located in the front of the engine. The ignition timing should be set to factory specifications whenever a tune-up is performed. Adjusting the ignition timing at this time will compensate for small changes in timing caused by wear of the timing chain and distributor drive gear and help keep your Mustang running at its best performance. The equipment required for this adjustment is minimal and available at your local auto-parts store.

Tools Used: Socket set, Timing light, White tire chalk, Shop towel

Set Engine Timing

Remove any grease and grime from the timing tab and harmonic balancer using a shop towel to wipe them clean. From under the vehicle, mark the timing scale that is etched into the harmonic balancer by rubbing it with the white tire chalk. This will highlight the scale so that the timing can be read easily. Start the engine and allow it to run until normal operating temperature is reached on the instrument-cluster temperature gauge, then turn the engine off.

Loosen the distributor hold-down, located at the base of the distributor, using a 13 mm socket, ratchet and extension from the socket set. Remove the rectangular, gray timing plug from its connector. This plug is plugged into the end of a two-wire electrical connector that breaks out of the main wiring harness near the distributor.

Attach the battery clips on your timing light to the battery. The black clip is attached to the negative battery terminal and the red clip is attached to the positive terminal. Snap the remaining inductive pick-up around the number-one spark-plug wire. On the Mustang engine, the number-one plug is the front plug on the passenger side of the engine.

Start the engine and aim the timing light at the timing tab on the front passenger side of the engine. Turn the distributor to line the timing tab up with the 10-degrees marks on the harmonic balancer. Tighten the distributor hold-down, and recheck the timing to verify that it didn't move when the distributor was tightened.

Turn off the engine, and reinstall the timing plug. Remove the timing light and test-drive the car.