I got my RS back in June. It was completely stock when I got it. I had an exhaust put on it, which has a
back fire when shifting. I replaced the donut gasket, but looks like the leak is coming from the slip fit flange at the muffler, which cannot be welded as the pipe is SS and the muffler is titanium. car has 70,000 miles on it. The front O2 sensor was replaced in 2001 by the recall. I ...