Ok I have an '00 EX Coupe Auto with AEM SRI and Apex'i WS2 catback exhasut. Last week I replaced my stock cat with an OBX High Flow cat and yesterday the CEL came on while I was driving home from work. I jacked up the car and everything looked good, so what could the problem be?
I get CEL after installing High Flow Cat
- Thread starter TripeoXxX
- Start date
Its obvoiusly throwing a code because of the cat you installed. The computer notices that there is a differrence in air/fuel, in the cat, which may not be in between the min and max allowable.
Check to see what code its throwing and search for in online.
Check to see what code its throwing and search for in online.
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http://www.honda-tech.com/zerothread?id=682412TripeoXxX said:
The test jumper is in the same location for 96-00 civics.
you can use a resistor in the circuit that goes to the o2 sensor to fake a good o2 sensor reading. its not a great idea though since your ecu uses your o2 sensor's values to modify fuel tables when running in closed loop. it'd be like basically running in closed loop and open loop all the time, only you're closed loop would have different settings than open loop lol (all u pgmfi geeks will know what i'm talkin bout) 
not if done right, and you'll only be in closed loop under about 20% throttle and when your car is cold. so the o2 sensor would only give fake values under those conditions. but u'd want to make sure u give it a value close to what it would actually sense or else you might run rich/lean, depending on temp and other conditions.
lol let me know if i'm talking over your head, i'm running a self-tuned standalone system called uberdata on my car to control fuel maps for the turbo so i've just started to learn some of the honda ecu stuff. i'm way far from being a self-proclaimed "expert", but i know enough to help people out.
im not gonna be runnin a cat (however i am turboin so that'll get rid of all the ratty noise u'd have in a n/a catless, but a nice magnaflow resonator would take care of that). shifty35 off of turbod16 was telling me he passed the carb testing w/ a turbo d16, no cat, just a test pipe with a cat heat shield on it. add in almost 30hp gains w/ no cat, and he sold me on the test pipe idea.