O2 Sensor issue on 4N Single turbo setup

[victorboost]

Hi, I recently started getting these codes on MHD regarding the O2 sensor. I am running the 4N motorsports kit with external WG.

I haven't had the chance to bring into shop, and for all i know O2 sensor might just need to be replaced. Any feedback would be appreciated. Car runs fine.

[b_w.]

Is your downpipe on securely? If your exhaust hanger wasn't welded on in the right spot I find the vband clamp will bend and will let air in.

[victorboost]

Originally Posted by b_w.

Is your downpipe on securely? If your exhaust hanger wasn't welded on in the right spot I find the vband clamp will bend and will let air in.

Yep the downpipe is on good. The code only started popping up after around 3 months of it being on that tune.

It only happens after I build boost and the wastegate opens. My theory was that when the wastegate opens, it sucks some atmospheric air and the o2 sensor reads excess air. Tuner suggested to replace the o2 sensor so I'm going to try that first.

[carbon-14]

Change the sensor? Any changes?

What turbo you go with?

[b_w.]

Can also check that turbo to manifold bolts are tight. I had to go back and re torque mine.