After I changed my header gaskets, and put copper RTV on the collector gaskets, that is supposed to be 02 sensor safe, my 02's were split by about 25, and my car would start to miss. So I put in my old 02's which were fine, and now the 02's are reading fine. So if you use RTV on the exhaust system, take out the 02's.

 

You know, I just did my intake manifold and egr with copperseal, and promptly got an 02 sensor failure code.(under 8K miles on the 02's) I just pulled the sensor, and hit it with some contact cleaner and a wire brush...works fine now.

 

I did the same thing with mine and got no codes. Maybe I was lucky. I wonder if the fact that I let it dry for several days helped.

 

Why you used RTV on header gaskets is beyond me.....

WTF M8

 

I did the same thing on my header gaskets and also got the "slow responce" code for both sides. I really think that you probably need to let it dry overnight before running the car.