I have a 2000 silverado 4.8 with dual exhaust. The exhaust was on the truck when I bought it sounds great. Recently I started hearing a wisping noise so I decided to investigate. I found a leak on the passenger side exhaust pipe where one of the welds is. How should I fix this: muffler shop, jb weld, duct tape?? Its a small hole so I dunno. Also the right exhaust pipe seems to have formed a pinging sound. Im not sure why, it seems like its coming from where the o2 sensor is. If i hold the pipe it wont ping, if I let it go it does, almost like a small rattle. Any ideas?? Thanks in advance!!