Well a few days ago I installed some headers, everything sounded ok at first. After about only 5 mins of driving I started hearing a very loud fluttering noise. (best way I can describe it is if you took a piece of paper and stuck it into a moving bike spoke) I was thinking maybe it was a leak, I checked all the bolts making sure I didnt leave anything loose. I did use the old gaskets, could this be the problem? It never made this sound before the install. Any ideas? thanks