With strobe light:

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Aim strobe at ignition timing notch.
Adjust ignition timing, if necessary, by turning distributor.
Check idle speed and CO content.
NOTE: Idle speed and CO content cannot be adjusted. If deviation from specification exists, make the necessary repairs.
Press --> button.
Press buttons -0- and -6- to select "End Output" function 06, and press -Q- button to confirm input.
Test operation of three way catalytic converter, refer to THREE WAY CATALYTIC CONVERTER (TWC) .
Refer to notes on, refer to THREE WAY CATALYTIC CONVERTER (TWC) after completing emission and idling test.

Fig 1: Locating Ignition Timing Notch (1.8L - Engine Code: ACC)
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