CO-Adjustment

Fig. 304 AIR-MASS METER WITH CO ADJUSTMENT SCREW:

NOTE:
CO is set at factory and the adjustment screw is sealed by an aluminum plug. Fig. 304. Adjustments are therefore only necessary when CO is out of specified tolerances.

Fig. 259 REMOVE TEST PLUG:

1. Connect a CO meter after removing test plug in front of catalytic converter. Fig. 259.
2. Connect tachometer.
3. Run engine to operating temperature.
4. Ground blue - white wire at test connector located in front of driver side strut tower.

Fig. 329 ADJUST IDLE SPEED:

5. Check and adjust idle speed with air conditioner off (720 RPM). Fig. 329.
6. Remove ground wire from test connector.
7. Engine speed should now be 750 ± 20 RPM. If idle speed is incorrect, see "IDLE SPEED" for more adjustment procedures.

Fig. 258 DISCONNECT LAMBDA SOND (OXYGEN SENSOR):

8. Disconnect Lambda sond (oxygen sensor). Fig. 305.
9. Check CO content (0.4 - 0.8 %).

Fig. 306 REMOVE CO PLUG:

10. To adjust CO, turn off engine.
11. Drill two 2 mm (0.08 in.) holes into the plug that seals the CO adjustment screw. Fig. 306.

Fig. 307 CO ADJUSTMENT SCREW:

12. Remove plug with needle nose or circlip pliers.
13. Start engine and run to operating temperature.
14. Adjust CO content to 0.6 %. Fig. 307. Adjusting range for screw is 15 turns. Counter clockwise reduces CO content, clockwise increases CO content.
15. Reconnect Lambda sond (oxygen sensor).
16. Turn off engine. Disconnect all test equipment and reinstall test plug into exhaust pipe.
17. Seal CO adjustment screw with new plug. Tap new plug into position.