I've had mine open, chasing the exact same issue. But it's been so long since I did it, I don't remember the specifics. I would definitely suggest taking it indoors, on a clean & well lit surface, to open & service it. There's a few small bits that could easily get lost. Also, when separating the "piston" (for lack of a better term) it twists/threads in/out. Be mindful of where it's positioned prior to taking it out. The only real change/mod I did to mine, was swapping the mounting bolts out for a pair of 5mm hex head bolts. Easier to deal with in the future, since the angle of approach for a screw driver is somewhat blocked by the rest of the intake plumbing. Ultimate, it's not that difficult of a service. Just take your time, make sure everything's cleaned, and be mindful of how it's all positioned when you take it off the intake housing.
