Adjustment W/ CO-Meter
Fig. 397 CONNECTING CO TEST EQUIPMENT:
1. Connect tachometer.
2. Remove the test plugs in front of catalytic converter.
3. Connect CO-meter. Fig. 397. Use VOLVO tool #5151 or equivalent.
4. Run engine to operating temperature and 10 minutes beyond.
5. Open the oil filler cap on valve cover.
Fig. 326 IDLE SPEED TEST CONNECTOR:
6. Ground red - white wire at test connector Fig. 326. located in front of passenger side strut tower.
Fig. 396 ADJUST IDLE SPEED:
7. Check and adjust idle speed with air conditioner off (700 RPM). Fig. 398.
8. Remove ground wire from test connector.
9. Engine speed should now be 750 ± 20 RPM. If idle speed is incorrect, see "IDLE SPEED" for more adjustment procedures.
Fig. 399 CHECK TIMING:
10. Check ignition setting (16° ±2) at idle speed. Fig. 399. Timing can only be checked, no adjustments are possible.
Fig. 400 DISCONNECT LAMBDA SOND (OXYGEN SENSOR):
11. Disconnect Lambda sond (oxygen sensor). Fig. 400.
12. Check CO content (0.2 - 1.0 %).
Fig. 370 REMOVE CO ADJUSTMENT SEAL:
13. To adjust CO, turn off engine.
14. Drill two 2 mm (0.08 in.) holes into the plug. Fig. 370.
Fig. 371 CO ADJUSTMENT:
15. Remove plug with needle nose or circlip pliers.
16. Start engine and run to operating temperature.
17. Adjust CO content to 0.6 %. Fig. 371. Adjusting range for screw is 15 turns. Counter clockwise reduces CO content, clockwise increases CO content.
18. Reconnect Lambda sond (oxygen sensor).
19. Turn off engine. Reinstall oil filler cap. Disconnect all test equipment and reinstall test plugs into exhaust pipe.
20. Seal CO adjustment screw with new plug. Tap new plug into position.