My car is OBDII, so I have two o2 sensors. One before the cat and one after.

I started getting a CEL when I put on my header. It was made for the D16Z6 and I have a D16Y8. My factory o2 sensor is at the top of the exhaust manifold, but the header has it at the end of the header. I had to lengthen the wires quite a bit, and since then, the CEL goes on. I pulled the code at an automotive place and it says Slow Response From O2 Sensor. Once reseted, the CEL would come on about once every two weeks.

Now I put on a high flow cat. The problem was the O2 sensor bungs were in front of the cat, so my first and second O2 sensor are right next to each other. I did some research and found that the first O2 sensor is responsible for making sure of the 14.7:1 air-fuel mixture is correct and makes adjustments based on it's reading and the second O2 sensor makes a comparison to see what the cat burns off.

What should I do? I believe the engine just goes with a generic air-fuel mixture when it can't get a reading from the O2 sensor. And VTEC still kicks in, so the CEL isn't affecting that fortunately. Everything runs fine. But now I have a constant CEL on from the O2 sensors. Is there a way to bypass this at all?

 

You have 2 options.

1. Get an o2 simulator.
2. Get a bung welded after the cat and plug the old bung.

 

How do the 02 simulators deal with the heater? Do you have to splice into your primary 02 harness for the heater signal?

 

O2 simulator?

I'm thinking I'll just go with an OBD1 conversion and run a chipped P28 ecu to get rid of the O2 sensor reading