October 30: LEMON manuals on a temporary server, it is slow and having issues, download the manuals you need! Later in November we will switch back to the fast server.

Code Enable Criteria

Engine speed is 1500-3200 RPM.
Loop status is closed.
Calculated airflow is 7-25 grams per second.
No CMP, CKP, ECT, EGR, EVAP purge solenoid, fuel trim, IAT, MAP, misfire, or TP sensor DTCs are set.

DTC sets when average response time of lean-to-rich switch is greater than 140 milliseconds for greater than 100 seconds, or average response time of rich-to-lean switch is greater than 225 milliseconds for greater than 100 seconds.