I bought some racing headers for my 04 civic lx,dont knowwhat brand of headers.But my stock headers have the cat.conv. built in it,so when i removed the factory headers and installed my after market headers..BOOM! damn CEL comes on!, then the o2 sensor wires aint long enough for the 2nd sensor. any suggestions?

 

you need to put on a cat. from a ex or dx model
as far as the o2 wire you need to to cut it & add some wire inbetween it to make it longer- dont mix up the wires

 

DO NOT CUT IT. GO HERE www.o2simulator.com

 

I did Put a new cat. on it from a ex model,but the CEL light is still on,i have two black wires that go to the o2 sensors maybe i got those mixed up

 

the CEL is still on because even though yeah u have a cat, all the increased exhaust flow is throwing your sensors off. And yea, theres also a chance you screwed up splicing the wires. I'm in the same situation and i just gotta get an o2 simlator too.

And Remmy, when you say dont cut, you mean don't extend them? Because even with the o2 simlator, you still have to splice into the stock sensorwires to get a 12V and a ground, and you also have to just cut the stock signal right off and wire in the new one from the simulator.

 

Well fellas i had the two black wires that go to the heat core in o2 sensors backwards, as soon as switch them the CEL light went out!!! thanks for the help

 

congrats you're lucky man, with the increased flow you usually get the CEL even if the wires are right