I decided to finally install my Mopar Mids on my '99 R/T, and rip the whole exhaust system off. It was stock except for a flowmaster muffler. I have 4 oxygen sensors in the stock system, 2 in the lead pipes and 1 after the cat as I expected. Then I found this extra O2 right in the beginning of the cat where the 2 lead pipes go in. What is the purpose of this O2? I know it's a CA emissions thing, as my first '99 R/T only had 3 sensors.
When I get my exhaust done next week, I wasn't planning on having this middle sensor put into the system, and eventually want both the "rear" sensors tuned out. What will happen if this middle sensor is not in the system right now? Can I just plug it in and zip tie it to the frame?