I have a d16y7 honda civic. I just bought a 4-2-1 header. My stock exhaust manifold has two port holes for the oxygen sensor. Now, this new HP header has only 1 port hole. The guy from the shop told me to leave the second oxygen sensor tie up and won't be any problem> Is this right? Do they sell the Header with two port holes.

 

Yes they sell headers with 2 port holes. However, you got a header for an OBDI car. Only use one O2 sensor. and your vehicle being 96 or new is OBDII.

Yes, if you leave the second O2 out in the air you will be fine....it's job is to see clean air. I would suggest wrapping it in tin foil to protect it though.

 

Thanks
I'll try that but does it give you any codes?

 

Is you engine from a DX? If so you had a cat/header combo stock and you went to just a aftermarket header. If you were to weld in a cat after your header you could screw it into the bung on the cat, other wise just tie it up wrapped in foil. You will probably have to weld in a cat if you live somewhere where they have emissons.

Thanks, J