In the very top pic with the vacuum lines, it 'appears' to be the VSV that applies or removes vacuum to the ADD (Automatic Disconnecting Differential) on the front diff. The vacuum lines should connect to a vacuum cannister in the fender in front of the passenger side front wheel.

Sorry I can't help with the rest of the pix, I have a 3.0 V6 in my 4Runner and not the 4-cylinder.

Mike in AR