I was looking at the service manual the other day and I noticed something odd. According to the service manual the sensor in the stock header is an o2 sensor, but the sensor in the second cat is a catalyst temperature sensor. Is there a difference between an o2 sensor and a catalyst temperature sensor? I would like to think there was, but I don't know much about it. Anyway I'm just trying to understand how the ecu fits into the exhaust system better so that when I upgrade the exhaust system I can keep the ecu happy. Thanks in advance guys.

 

good question, all i know is that they are not the exact same thing because the first one cost a **** load more than the second.