Just recently installed a new TurboXS up pipe on my 03 WRX. I accidentally bought one without a spot for the 02 sensor. My local garage told me I'd be fine without it and it would not throw any codes. However, after the install my car is throwing a CEL. I used my accessport to pull the code and it is p0031 - HO2S Heater Control Circuit Low. Is this because of the missing 02 sensor or did I damage another 02 sensor during the install?
I've found lots of information on it, but a lot of it is conflicting. Some posts say p0031 has to do with the 02 sensor in the manifold only which is why I'm asking.