CEL on and off

[gehjl]

It was about a month ago when my CEL just came on out of nowhere. I went to Autozone and had it read, it was the Primary O2 sensor. Don't remember the code #. So I was like okay and headed to get my oil changed. I left the dealership and I drive maybe like 5 miles and the CEL goes away. Ever since then the CEL would just come on for 1-2 days then disappear for like a week.
2 days ago, it just came on all of a sudden and went into limp mode. I had no time to check anything since I was going to school, so I just reset the ECU. Yesterday I redlined my car and a min after, the CEL came back on, same code Primary O2 sensor. Then about 12 hours later, the CEL went away.

Im not sure if I need a new O2 sensor, it's just confusing my why it keeps coming on and off. I plan to jack it to see if maybe it's loose or something as I had to put on the donut gasket at the header/cat a few months back. Just wanna know what to try before having to spend 200 on a new one.

Thanks guys.

[Tnhatch03]

That is how one knows it is the o2 sensor. The CEL will come on and once you turn off the car it will go away and come back after a while. I would fix it ASAP. hth.

[gehjl]

Dammit, 200 I didn't wanna spend.

Prob stupid question, but can i switch the primary with the 2ndary?

[Tnhatch03]

I do not think so. I believe the tips are different, but I may be mistaken.

[4angrybadgers]

They're different sensors. Do it right the first time and get a proper OEM replacement.

[boyurlazy]

i have a new one that i can sell you for 160 shipped... denso.