CiaranPW 5 Report post Posted December 4, 2021 Hey guys, I've recently installed the Tomei UEL headers and got a check engine light. P0031 reads as the o2 sensor bank 1 which I believe is the one before the cat. From what I've read the error code for installing headers and removing the cat is something else. I've been able to get rid of the CEL with a resistor in the plug but have been told it could give a false reading for the air to fuel ratio and cause engine knock. Has anyone done something similar and it been safe to drive? Or have I butchered the sensor and need to replace it? Any help would be appreciated, Thank you. Share this post Link to post Share on other sites
