Just did a little research and wanted to chime in a bit with what I found / thought. Looks like a CEL will definitely happen (eventually) after removing the SAP/SAI. I'm seeing P1415/2D06 as the code, but I'm not 100% sure on that.
After thinking, I remember reading that the BMW actually looks at the O2 sensors to determine SAP performance, so installing a resistor on the SAP's plug wouldn't help with CEL's at all. I read of one guy using an O2 'simulator' to simulate what the O2 sensors should send to the DME for the first 30 seconds after starting (when the SAP would be running).. but that's not really the way I'd like to go, either.
Further, it looks as if many different potential problems with the engine can all result in the same fault code that the SAP failure (or removal) would throw, so perhaps simply removing that fault code from the DME tables (if that's even a thing) would not be a wise solution.
I'm starting to think that the only way to really do this well is to somehow change the tables in the DME's software to reflect N52 values.. but it's starting to get way over my head since I know so little about how the computer monitors and evaluates the SAI system's performance. Hmm.. I wonder if this is an area of the DME software that could simply be removed, resulting in an N51/N52 DME software hybrid of sorts.
.. just trying to understand all that I can before reaching out to the pros.
