Hello Adam! I'm very sorry for disturbing you, I can imagine, how many people were bothering you regarding this matter...I spent a lot of time looking for person like you, who could be wise enough around VP44...I have two of them opened, the first one has a problem with electronics, it works, both timing advance solenoid and fuel metering solenoid, but not correctly, idling is very erratic, I guess every other cylinder fires, timing jumps, but when accelerating everything is fine and works...It happened a few weeks after the pump died and I had to fit a new IAT...I ran out of ideas so I bought another pump, and there developed the timing problem, I can activate the solenoid with diagnostic, but cam ring does not move...but my biggest problem is - both advance pistons are not stuck, moving freely, they are worn out similarly, both cam rings look like new, they do not seize or get stuck...but neither of those advance pistons from both pumps sticks...