ok i have a 99 si and last night i got on it a little on a on ramp like we all do every now and then well when i got close to home i heard what sounded like an exhaust leak well i popped the hood and noticed that some how my header backed about 5 bolts out so i tightened those down and then i fired it up this morning and i herd it again well i start it up and it sounds like a dang piston is flopping around in there. i think it is a bottom end barring. :.( so i think its time to go h22 any one think they now whats wrong, any input is appreciated.