I am in the middle of doing a H/C/I swap. I am going from a stock intake to a explorer intake. I have an 89 GT. My friend did work on the intake and had to leave. On the very back of the intake there is some sort of plug that looks like it had a hose on it but i don't know what it is. THe plug is plastic and has a little tube out the top of it. What is this, is it for a vaccum? Do i need to hook a hose on to it? Also the stock plug is larger than the hole on the back of the explorer so i can't reuse the stock one. Thanks nick