I changed the sensor myself with a Denso Sensor on my 2012 Avalon, The CEL went off after 50 miles, thought I have it fixed. It came back again with the same code in maybe 20 miles and now keeps doing it every 40-50 miles. Thought the sensor that I may have bought was bad and got another one and replaced it. Same output. CEL turns off and on every 30-50 miles. Any suggestion what might be wrong?