So I recently got a CEL of P0420, so I ordered the J style defouler. However, I have having trouble installing it as the defouler hits the catted downpipe shield and maybe even the pipe. I can't get the defouler connected all the way. I did get it to stay in, just not all the way in and then put in the o2 sensor, but I believe I still need to tighten it more. Now my car is throwing the P0141 CEL. Anyone know what to do? Thanks!