isnt the ais just some sort of vacuum? from the looks of the system i would think its some sort of egr valve
which just catches exhaust gases..
if this is the case i wouldnt worry much, it should fly right out the pipe when started up.
you could do the thread tap. or if you didnt have the tools and didnt want to spend money. it looks like a thin metal so maybe you could just put a small flat head and bend it. maybe use a hammer to wedge it till you could get some needle nose in there. i use this method for dowel pins all the time.
maybe some that knows a bit more on the motor could tell where it leads.
Opposite of a Vacuum
A (air) I (induction S (system)
It's is metered air that gets pumped into the exhaust to aid in the burn of exhaust gases in the stock pipes.
Since the stock pipes are restrictive, extra air is introduced, but with a more free flowing after market exhaust the extra induced air is not needed, and ends up causing more problems than what it is worth. Can cause excessive decel
popping, can cause a backfire, and in the worse case, can cause flames to shoot out the pipes. That's what happened with a friend that I did his carb
work, he forgot to bring the AIS plugs, it was dark when he left, he had purple flames shooting out. next day he did the AIS and was good to go.