Diesel Data: Automotive Repair

Ignition Timing: Adjustments

*** This procedure has been updated by TSB #26-07-87

Before checking or adjusting ignition timing, be sure:
Engine coolant temperature is at operating temperature, 85-95° C (185-205° F).
Lights and all electrical accessories are OFF.
Transaxle is in NEUTRAL.
Front wheels are pointing straight ahead (vehicles with power steering).
Parking brake is SET.

1. Connect a timing light to the number one cylinder according to manufacturers instructions.










2. Insert a paper clip in the connector (1 pin) of the harness and connect the rpm gauge.
CAUTION: The connector contact should not be separated. The paper clip should be inserted along the terminal surface. If the paper clip is inserted incorrectly, the paper clip may become caught and cannot be removed. For male pin, insert paper clip into the lock tab side. For female pin, insert the paper clip into the side opposite the lock tab side.
3. Start the engine and let it run at curb idle speed. Curb idle speed = 650 to 750 rpm.

Ignition Timing Adjustment Connector:






4. When checking the basic ignition timing, stop the engine and disconnect the water-proof female connector from the ignition timing adjusting connector. Connect a lead wire with an alligator clip to the ignition timing adjusting terminal to ground it.
5. Check the basic ignition timing and adjust if necessary. Basic ignition timing = 6° to 10° BTDC.

Distributor Mounting Nut:






6. To adjust ignition timing, loosen distributor mounting nut and turn distributor housing.
7. After adjustment, securely tighten mounting nut.
8. Reconnect ignition timing adjusting connector which was grounded in Step #4. Restart the engine and ensure ignition timing advances to actual ignition timing. Actual ignition timing = 10° BTDC (15° BTDC at high altitudes.)