A while back I put a Dynomax cat-back on, replaced the third cat and resonator with a custom y, and I cut open and emptied my cats and welded them back shut. Worked great, no exhaust leaks, sounds good, free flowing. Well, I made up a pair of MIL eliminators for the downstream O2 sensors. Fired it up...no light...for about a week. The check engine light is always on now, and I've assumed it was due to the cats (or lack there of). I've been having other issues lately, so I went and got the codes pulled today, expecting to see several...couple for the downstream O2's and maybe one for something else. Nope. Only one code, P0174, which says bank 2 is lean. This is not an O2 sensor code, just a lean bank code. Any thoughts on this? What should I look at? Wouldn't the lack of cats trip a code for the rear O2's? Thanks in advance guys.