Keep getting code 153

If you dont have LT headers, I would say you just have a lazy sensor. Try letting the car warm up for 3min or so before driving it, it might help.

That is, I believe the code that I got on my OR/X except mine would stay on. Yours may go on and off due to the cats, so have you tried MIL eliminators? Or do you have a tuner?

I was lucky and found a diablo for cheap (150$) and bought it just to turn off the CEL.

Thats is on 02 sensor code, NOT a monitor code...

Get the mil eliminators, or a tuner aftermarket cats are not heating up fast enough for the o2 sensor.

bank 2, sensor 1 is an upstream 02 code- If it had something to do with needing mill elim's or your cats it would say sensor 2. Your 02 sensors are far in front of your cats, your cats not heating up fast enough has nothing to do with it...

My car kept throwing the same code after I installed my catted H. To be clear here, I will always be referring to the pair of 02 sensors that the exhaust reaches prior to entering the cats:

What I found to be the problem in my case was that the 02 sensor location on the H-Pipe I bought was further upstream on the pipe than the stock 02 sensor location. I am told that the more forward sensor location was the location used for earlier 99-04 Mustangs... that explains why I had to buy 02 sensor wire extensions. Anyway, since my car was an '04, the exit spout of the AC condensation drain line was directly above this more forward location of the 02 sensor. So, what I believed to be happening was that I would run the AC, then water would drip on to the sensor and short it out/inhibit its breathing/ otherwise keep it from working. The drain line never dripped onto the 02 sensors on my stock mid-pipe because the sensor locations were further downstream on the pipe and therefore out of the path of the flow of the drain. I ended up making a shield for the O2 sensor out of aluminum foil but kept it loose enough so it could breathe, and ever since I have had no problems.

Could it be that you are having the same problem? Have you been running your defroster in this cold weather? Check to see if your AC drain line is directly above your passenger side 02 sensor. Good Luck.