hi there, i got a cat-back done on my 99 integra se 4 days ago. A day after the install my check engine light goes on. I reset my ecu. the next day (yesterday), the check engine light came on again. I figured out today, that the high-flow cat/resonator is actually just a resonator (the right part was ordered, wrong part is now on my car). I wondered why i needed another O2 bung installed, well, my resonator is not meant to pass emmisions. I tried resetting my ecu again today, is it possible that my check engine light will stay off, or am i stuck buying another cat......any input would be great!

 

you can buy or make o2 simulators that plug into the second o2 housing....or try putting foil around the second o2 sensor and leave it out of the housing, a friend of mine is doing that with his car and no check lights anymore. good luck. i personally would send back the wrong part and get the high flow cat, but thats just me