The master on mine is #3 which has the white paint on it. I don't know if it's fully closed or not as the manual(and others) say not to adjust it. #4 is the one that's fully closed.
Yes, it has the white paint on it. 2016 as well.
Sounds like a good idea. On my next sync I may try this if...
I'm sure this has been covered before but haven't found any info on a late model FJR. I performed my second throttle body adjustment on my 2016ES. First I tried to use a two cylinder harmonizer and adjust one cylinder at a time against the master (#3) as I like how the harmonizer has no bounce...