I called Cobb tuning today about CEL's and 2012 GT-R's and was told they are getting complaints of CEL on just mid pipe. No issues on ealier models, just the 2012's. I was told there would be a good chance( at least 50%) of a CEL with just a mid pipe and I would need a tune or relocate the O2. I know a few 2012 owners on this forum had some issues with just a mid pipe . What is it about the 2012 's ? I was all set to do just a mid pipe( for sound) as I do not want any warranty issues, but now I do not know what to do.