[WhiteFury]

So when I put on my catless downpipe I got two non-Fouler bungs and drilled one of them out due to the length of the oxygen sensor and plugged it in to try to prevent a check engine light and to slow the flow down to the secondary oxygen sensor.

Intermittently I have been getting a weird issue where in fifth or sixth gear around 2000 RPMs at light throttle it feels like the car is lightly surging. Almost like it's entering boost but then not entering boost white power loss and power game but it's very slight.

I am getting the code 2D1B.

The JB for a couple of times indicated this was a throttle input position one sensor malfunction. However many other locations have listed this is being the secondary O2 sensor being too lean.

Jon over at Burger said he can tell by looking at a log if my primary oxygen sensor is working, how do I know if my secondary oxygen sensor is blown or if it's just malfunctioning due to the fact that it's plugged into a non-Fouler?

Jon said that the secondary oxygen sensor can affect the tune however in most vehicles I have ever driven the secondary just tells the computer if the cat is working.

Should I replace the sensor?