P0240 CEL/MIL after 034 Motorsport HFC install

First time posting, sorry if i posted this issue in the wrong area. So I installed a 034 HFC with Bosch o2 sensor spacer. After putting on 120 miles i got a CEL. I do have an APR stage 2 none test pipe file. Im trying to work my way around not reflashing. Any suggestions on resolving this is issue? Any recommended o2 spacers