check engine

So I recently got a set of downpipes put on my Q that had an O2 sensor J-bend on it already. They were downpipes from Fast Intentions. When I had them put on I had also wrapped them in a heat wrap. They came out freaking phenomenal for the first week and then the moment I went to go start my car...

2014 Infiniti Q50 Sport. Malfunction Code: P0101. Cleaned MAF sensor and throttle body. Check Engine light went away, but major delay while shifting remained, barely any throttle response even when flooring the car, and RPM’s jump up and down even when idle. Air filter is clean, connections seem...