I'm glad you got your saw running!Don't want to hijack my own thread getting into Usa vs China made. The real story here is this choke on my saw and apparently lots of others have been set incorrectly at the factory. Their QC failed.
I guess the real point is the Stihl company failed to supervise their own workers, regardless of the location. Many of us might like to think that made in the usa means it's better, but ultimately it is all about quality control.
One other thing regarding choke and winter: Is it cold where you live? Last year, I had trouble starting/freezing up a 170 that I use in tight spaces with small wood/branches (like limbing spruce and fir trees and thinning thickets). After talking with the helpful folks here, I place up to two pieces of tape on the bottom (at 1.5" and 2") of pull-cord housing grill. When it is really cold (-20ish), I have learned to also run a piece of tape on the little air inlet grill on the carburetor cover. As the day warms, I begin removing tape. My saw seems to like to run a little rich in the winter. I get more power, but less fuel economy out of it that way. The tape keeps it warmer and drier while also adjusting the air intake.
The tape on the bottom also keeps snow out if you are setting it down in loose dry snow (to drive wedges, drag out some branches etc.)- particularly when it is idling. Note: I also bought a hunk of plastic that can be installed in winter. It does pretty much the same thing as the tape, but I find the tape easier and cheaper. The hunk of plastic for winter use is sitting on the shelf.