AAM HFC And CEL Question

Duke of Super

Hi All,

I have a question regarding my HFC's i installed about a month ago.

Install went ok but 1 of my o2 sensors was seized in the stock cat so the o2 sensor ended up cross threading. I bought a new o2 sensor and installed the hfc's without any problems.

Skip forward 1 month and 2xxx km later...

Going into work my cel lit up so when i got to work i checked the cel code 2098 (lean condition bank 2). I cleared the code, crawl under the car and gave the hfcs a tighten...about 100 km later cel came back on.... Now 2098 and 0420 (bank 1 cat not efficient). So now im scratching my head as to what the problem could be. Cleared the code now my car only throws the 2098 and the 0420 hasnt come back. Idk if it is a coincidence or not but the "old" o2 sensor is on the side throwing the 0420.

I should also note i have short tails and k&n typ. Intakes so am i just in need of a tune??? Would that explain the 2098? Why wouldnt i get a 2096 as well? :S maybe a gasket isnt sealing?

Any thoughts are appreciated!

Thanks!