So, I managed to kinda sort the issue somewhat... I got the AFM out of the car and opened up eventually... a lot of cutting silicone seal and trying not to slice up fingers in the process. Eventually though I had it open, and thus the innards were exposed for all to see...
After checking the vane was free moving and fine, and the airways were all clear, I set about going over the internals. The carbon track was somewhat worn, but not too much considering the age of the part. I cleaned up the track and the contacts as best I could (a sheet of paper apparently has enough abrasion to clean them without damage), and pondered how to reseat the contacts onto an unused are of the strip. As it turned out, undoing the three screws holding the PCB to the frame allowd the board to shift ever so slightly, resulting in the needed adjustment. After ensuring the contacts weren't drifting off the track, I did em up, and all seemed well.
I checked the air temp sensor in there too (and stupidly forgot to take a picture, but it's in there) by blowing and huffing on it, and checking the resistance changed properly. All seemed good, so reassembly and testing proved all worked fine. It seems to have given me smoother running of the engine overall, with less misfires, but ultimately they still persist with the low RPM issue, so I can honestly say the AFM isn't the cause. I did remember I hadn't checked the TPS on this car, so a new on is on order and I'm probably going to kick myself hard if that turns out to the cause. Failing that, I've still got the new O2 sensor to fit because lazy and it's been raining, so maybe somewhere in all this mess the cure lies.
We shall see...
Never use another Cav driver as guidance to a destination, unless you REALLY want to explore the country.
"Won't SOMEBODY please think of the scones?"
1.7TD Ethos (Slightly broken)
1.8i (Given up, going for parts)
2.0i (WHY won't it work?!)