mine doesn't seem to be operating properly. bad diaphragm, probably. i'll proabably just hold it open with some wire, for a while. i just want to make sure which lever position indicates that it's open. i tried tying it in each position, but the exhaust sound and pressure didn't seem to change as much as i expected, so it was hard to tell. i know removing the y-pipe is the best way to tell, but the y-pipe was a pita to bolt back on after i swapped my engine, so i'd like to leave it on. probably got bent a little, offroad. thanks.