Dumb Question, What reservoir is this?
 

Sup guys, Dumb question but i was looking under my hood at something yesterday and I noticed a reservoir tank that i never realized before. It's on the passenger side of the car right up against the firewall in the corner.

Whats it for, lol.. I was shocked that i never seen it before, And it was dark out so i didn't look into it to see where it led to.

It sounds like the subzero start assist system. It should have been removed at some point because madza admitted that it does absolutely nothing. The funny thing is my 90' GTU still has it installed, too. Just haven't gotten around to removing it yet.

Thread with more info: https://www.rx7club.com/2nd-generation-specific-1986-1992-17/how-does-sub-zero-start-assist-work-882472/

why thank you my friend, Guess that's why it was empty, lol. i will keep it that way