I have a 1997 Honda Civic EX and recently replaced OEM O2 sensor with an aftermarket one. The check engine light has been on ever since- and I am experiencing sluggish performance. I've heard there is a chip(?) for this... anyone have any suggestions??

 

did you replace the O2 sensor or did u just extend it?

 

It's a replacement. The original was seized onto the original exhaust manifold. When I put on a new header- I got a new O2 sensor.