u/Aborigine29

It’s a 2014 Volkswagen Jetta 1.8t. I do have a high flow catalytic converter on it. When I first installed the cat, I added a spacer for the o2 sensor and the codes went away, but now about 2+ years later they are back. I changed the sensor to a new one, and added a different spacer with a filter in it but the codes remain. After clearing them the time it takes for them to come back varies, but it’s within 1-3 drive cycles. Is it fine to just leave the codes or is there a way for me to tell the car it’s fine?