Welp do you have cats on the car? Your rear 02 sensors would be throwing you off because there are no cats.
Justin can turn off the rear o2 sensors via the SCT so you dont have this problem.

 

I have all 4 cats still on my car. Only thing that I can think of right now is that my EGR is not connected.

 

O_o that would make quite a noise under the hood if it wasnt connected.

The EGR can get caked up really badly with carbon, you can clean this out or buy a new one.

 

You could also have failing o2 sensors or even Evap system problems (Another issue I am having.)

 

My EGR is fine. While changing my passenger side header, we broke the EGR tube so I've pieced together my own temporary delete kit. I'm getting a code because of that. My o2 sensors seem to be fine, but how can I check?

 

Deleting the EGR believe it or not, could be causing the problem because the sensor is still looking for the data the egr isn't sending, just a thought.

 

With a EGR delete, I would think the car would be running more rich than lean. So I dont think the EGR has anything to do with it.

Buy a used tuner if you have to. I got my X3 for $220 shipped. Works like a charm even with the canned tunes.

 

Possibly. I can also see it being the problem since no exhaust gas is being recirculated into the cylinders, it's all fresh, cold air... I got a replacement tube that is going on tomorrow, so all should be good!

 

Yea, under normal deletion I could see, but with the EGR still on the car and the pipe broken this is causing the sensor to send bad info to the ecu.

 

I do not have the pipe connected to the car anymore. It was removed and the egr valve is capped off, but I can see your theory still being correct...