I highly recommend using foodsafe PG (lifetime supply for $10) rather than buying the packets from Ploom, since it is just marked up.
A month ago, my spring started getting sticky and there was a lot of drag on the mouthpiece when I tried to engage it. I decided to finally fiddle with the spring mechanism.
Firstly, I took the denta-pick and attempted to get the spring out so I could clean it. I failed, miserably. I ended up just jabbing the spring around. I then took the dentapick, dipped it in some ISO and delicately went into the spring area, jabbing the spring around. I then did the same with a small amount of PG.
Afterwards, I noticed that the spring was moving like it was when it was brand new. I let it sit on red-partymode for a good 15 minutes, just in case the ISO/PG fumes needed to dry out. Even now, a month later, the spring is moving very nicely and my MP hasn't dragged at all.