Sounds like the connection somewhere between that specific wiper arm and the inner drive cable. Ought to be some of the following:
Connection wiper arm - splines at the spindle. Not likely, but check.
Connection splines - spindle. I think the splines are screwed onto the spindle, then locked with a hex grub screw. Could it be loose?
Defect wheelbox, the spindle is not moved by the inner drive cable.
Defect inner driving cable.
Cannnot be anything in the wiper gear box, as long as the other two arms are moving.
If you look at CarBuilderSolutions' website, they have all these items, but I can't see any 32 vs. 44 teeth versions of the wheelbox. Might be a good idea to contact them about the wheelbox.
