Db1_77

I just completed my swap not too long ago, and I'm having issues with the idle. I crank it up and it immediatly jumps to 2K. and then it settles down to 1500 after a few seconds and just sits there even after it warms up.

There is a valve on the bottom of the TB that I'm not sure what it does. But it's plugged in as well, but no line running to the thermostat housing. I bought some 5/16 line to connect it, but it only blows air into the coolant and causes a rapid overheat. (A seal needs replacing somewhere.)

Any help on what this does?