hi everyone new here. Looking for opinions about an exhaust leak on my 02 ultra. You can hear it when accelerating. I thought it was the mid crossover pipe so I replaced it and no difference. Next I changed the complete egr valve and both egr tubes and no change.Changed the exhaust manifold gasket as well still same.Can't really feel anything down by the flex joint but it's hard to tell for sure. Is there any other places it can have a slight leak other than the things I have changed? Do those factory flex joints really ever cause a problem? Only thing I haven't done yet is replace the complete exhaust manifold and down pipe. Any ideas? thanks in advance