Is there any way to do this besides listening by ear? I guess I could shove a piece of paper or something flimsy up there to see if there are any gases coming out, but I would prefer to have my hands burn free. I have a slow response on my bank 2 sensor 1 02 sensor and I think the problem has to be an exhaust leak. I had this problem before I installed the s/c so I replaced the 02's thinking they were bad. I drove around for a few days and my CEL never came on so I assumed the problem was fixed. But when I was driving around tonight the CEL came on and when I checked my code it was the slow response thing. Soooo...can anyone give me a suggestion on how to check for a leak?