my check engine light just came on, when to karen to get one of those ODBII tester, and find out that the code that came out was (low sensor) for Bank 2, Sensor 2... you guys by any chance where the bank 2, sensor 2 is located at? I currenlty have pro-1 header, kentix tp, and pro-1 exhaust.

 

Bank 1 is passenger side, bank 2 is driver side.
Sensor 1 is before the cats, sensor 2 is after.

 

Probably due to the test pipes.

Also, if you haven't gotten tuned or reflashed yet, that would be a great idea to get your air/fuel where it should be.

 

happend to me too

 

What did you end up doing? Mine has been on for a while now and nothing has worked. The O2 sensor had a tear in the line so i got a direct replacement from Nissan. Turned right back on after i left only driving like 5 miles. Took it back and cleared the codes. Came back on. Took it to Autozone and they gave me the same code and said the same sensor was the deal. Disconnected the battery for an hour and its on again. I have no idea. I have stock everything. (Im new to this site and the "Z" craze. Trying to get figure out how all this stuff works.)