i just replaced the cat on my 99 civic and a week and a half later its throwing the code 67 again, could this be a problem in my o2 sensor wiring? i fucked with it to extend it a while ago and soldered it then wrapped it in electric tape...

so am i skrewed and have to get another new cat? or could it be the sensor wiring is jacked...?

 

Probably your homemade wiring. I had the same code and after I replaced my cat it went away. Maybe try rewiring it to oem specs or go get the piece you need from a junkyard. Your cat should be fine if you just replaced it.

 

what cat did you replace your OEM one with??? and what did you have to do with the wiring???

 

well i tried using my buddies teg cat and the o2 sensor is farther from the plug than the civic one... so i just cut the wires and extended them... well come to find out that the flanges are opposite so i couldnt use the cat. so i ended up replacing it with a used si cat. it drove perfect with no cel for 2 weeks and then all the sudden the cel came back on. any more imput would be greatly appreciated

 

why did you replace the orginal cat, what went wrong with it, did the inside melt and fell apart?? you should also get a new 02 sensor DENSO only, try e-bay there like $50 for a 4 wire universal