I did my swap a few months ago and I'm now getting a P0135 code. The MWR header gets a reading from only one of the cylinders (which seems odd). I've read this can cause the O2 sensor heater to burn out which would explain my CEL. Has anyone run this setup with no problems or do you put a bung further down before the CAT (to get a reading on all 4 cylinders?
Edit: New upstream O2 sensor solved the CEL
I just got this CEL code earlier today on my 2zz swap. It's related to the O2 sensor heating element. Just had a few questions I hope someone could help me with. The car runs great, how urgent is this fix? I have to pass emissions testing in 3 weeks. I replaced the CAT when I did the swap a few months ago. Is this something I can just reset the ECU and hope it doesn't come back on before the test? I read it could be a fuse, relay, or O2 sensor. Has anyone had this problem. If so, what was the resolution? Thanks in advance.