brandonl2000 
Car: 2003 GTP...107k miles, original o2 sensor to the best of my knowledge. **Still getting awesome mileage, leading me to believe it's fine.
So everything was fine and well with my car until we installed headers. I, of course with no cat, got the P0140 code. That's fine.
But I also got DTC P1133 HO2S Insufficient Switching Bank 1 Sensor 1...
So yeah. I used a zzp extension harness. I did not beat in the firewall because it didn't seem to hit, as of now theres a few centimeters between the sensor and the insulation in the tunnel, moved the engine all the way forwards and backwards and it never scraped, so I assumed it was good to go. Plus, if it hits, it's hitting insulation and not metal so I figured false kr wouldn't be an issue, and it doesn't seem to be either.
BEFORE the headers, I did not have any trouble codes at all.
Mr.OtherNick said this code is normal from headers. And I've heard from two others that regardless, I should never have any front o2 codes. And so I'm just confused.
So do I replace the sensor? Try to beat in the firewall? Tune the code out?
If replace the sensor, I have heard that ngk/ntk is a shorter sensor thus more clearance. But I also hear ONLY denso/delco sensors. Thoughts??
Thanks guys!!
