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 21

Problem with O2 Sensor feedback circuit. Occurs if engine temperature is above 170°F (77°C), engine speed is above 2000 RPM, but O2 sensor stays rich or lean for more than 22 seconds.