2002 Sentra SE-R Spec V: PO1706 Code Explanation & Engine Swap Issues

I own a 2002 Sentra SE-R Spec V. After my first engine failure due to a known recall, I performed an engine swap using a 2003 Sentra SE-R Spec V motor (identical model). The new engine features no logic hot wires, Nismo R2 cams, and a lightened pulley. My OBD2 scanner currently shows three engine-related codes: - PO0301: Cylinder 1 misfire detected — this is concerning as the vehicle doesn't seem to run smoothly. - PO0420: Catalyst efficiency below threshold (Bank 1) — likely due to the absence of a catalytic converter, which was not installed during the swap. - PO1706: I'm unsure what this code means and would appreciate clarification on its cause and implications. Can anyone confirm what the PO1706 code indicates in a Sentra SE-R Spec V with an engine swap? Any insights or troubleshooting steps would be greatly appreciated.