On my early 90’s Toyota Corolla there is a big rubber boot-like-thing which routes the cleaned air from the air cleaner to to the throttle body intake. You’d think it would be just a big round tube or a rectangular duct from the air cleaner to the throttle body. But no, it is very weird looking. The only thing that pokes into it is a small sensor which I think measures the intake air temperature.
It has two appendix-like things that seemingly are designed to simply poke out and consume whatever available engine space was there, and for no apparent reason that I can see. These appendages not connected to anything other than the duct itself, they are just THERE to provide empty space off both sides of the duct! One of these rubber appendages is sort of box shaped, and the other is shaped like an actual human appendix. Long and narrows to a point. I’m not making this up!
Anyway, what is the purpose for the the weird shapes? Any ideas why Toyota designers didn’t just use a simple round or rectangular duct shape to route the air from the air cleaner to the throttle body?