Air/Fuel Ratio

CO Test Port Location:

NOTE: There is no provision for an air/fuel ratio adjustment. The air/fuel ratio can only be checked.

PRECONDITIONING
1. Drive vehicle for 15 minutes (minimum). Shut engine OFF.
2. Disconnect battery negative cable for ten minutes to clear adaptive memory.
3. Disconnect oxygen sensor probe connector (green wire).

TESTING
1. Remove the exhaust test plug in front of the catalytic converter.
2. Connect the CO meter to the test opening.
3. Restart the engine.
4. Check the air/fuel ratio after the engine has reached operating temperature.
5. If the engine is working properly,

Reading should be: 0.4 - 0.8% CO

If the air/fuel ratio is not within specifications refer to DIAGNOSIS AND TESTING PROCEDURES.
6. Disconnect the CO meter and reinstall the test plug cap.
7. Reconnect oxygen sensor connector.