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Ignition Timing: Adjustments

Before checking or adjusting ignition timing, be sure:
Engine coolant temperature is at operating temperature, 85-95~C (185-195~F)
Lights, electrical accessories, and cooling fan are OFF
Transaxle is in Park or Neutral
Front wheels are pointing straight ahead
Parking brake is set

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

Tachometer Connection Location:




Engine Speed Check Connector With Paper Clip Inserted:




Tachometer Hookup:





2. Connect a tachometer. If using a primary current pulse detection type tachometer, insert a paper clip into the back side of the 1-pin harness connector, as shown above, then connect a tachometer to the paper clip.
DO NOT disconnect the electrical connector.

CAUTION: If the paper clip is inserted incorrectly, it may become caught and cannot be remove without damaging the connector.

DTM Control Terminal:





3. Ground terminal 10 of the diagnostic test mode control terminal with a jumper wire.
4. Start and run the engine at idle. Verify idle speed is at CURB idle.


Fig. 2 Ignition Timing Connector Identification:





5. With the engine stopped, disconnect the ignition timing adjustment terminal, located in the engine compartment. Ground the terminal using a lead wire with alligator clips (Fig. 2).

6. Restart the engine.


7. Aim the timing light at the timing mark and check BASIC ignition timing.


8. If timing is not within specification, loosen the distributor mounting nut and adjust by turning the distributor housing, then tighten the nut being careful that the distributor does not move.

9. Stop the engine. Disconnect the lead wire from the ignition timing adjustment connector and remove the tachometer and the paper clip.

10. Start and run the engine at idle.

11. Recheck ignition timing to ensure that it advances from BASIC to ACTUAL timing.

12. Remove the ignition timing light.

NOTE: (a) Actual ignition timing may vary, depending on the control mode of the Engine Controller.

(b) At altitudes more than 700m (2300ft) above sea level, the Engine Controller may further advance the actual ignition timing.