Hey guys new to this forum, just bought a G37 and love it so far! The stock cats that were on it were rattling / broken loose due to a bottom out on something from the previous owner.

Ended up buying some z1 highflows and installed them yesterday, started the car and CEL popped on. The typical p0420 code didnt pop on... its a p0051 and p1168 (closed loop control function, heater control function) for bank 2 sensor 1. It does still have a bit of an exhaust leak between the manifold and hfc flange that im still trying to resolve, anyone think that could be the cause of this CEL?? or is my manifold sensor toast now...

On a side note i was shocked when it said bank2 because i had no problems getting the passenger side out. The driver side stud on the other hand froze and had to cut the cats off, cut grind, and hair hammer the stud out. I would figure if any sensor was damaged during install it would be driver side one due to all the impact vibrations etc. Driver side however has no leak.

 

my testpipes leak few months ago but the CEL never came on. so i decided to put the stock cats back on for few days... but when i put the testpipes back in the CEL came on and off for few days, it took few times of disconnecting the battery for the CEL to go away.

 

Hmm yeah I tried clearing it last night after a little burn in time with the Snap-On scanner but came back after couple minutes. I called z1 about it and they said I prob have a intake or exhaust leak so thats whats making me guess at it. I just dont see how sensor 1 could detect a leak after it??

 

its the leak or unless you damaged or it was alrdy going out.
there sensetive,just replace it there cheap

 

Yeah the passenger side was really easy so I doubt i damaged it. I cant figure out why this side is leaking and the other side isn't. Still trying to get the leak resolved before i buy something i don't need. Went back and retightened the crud out of the bolts on that side and it was slightly worse... Guess ill pull it off and try some copper coat lol.