I am wondering what these parts do.

 

The smaller part on the right is the diverter valve for the heater hose. It has a vacuum line going to it. When youturn your heat on, it allows hot water to flow to the heater core. When you turn the heat off, it allows the hot water to bypass the heater core. The other item is for the AIR tubes in the exhaust manifolds. It houses two solenoids that the computer controls. It routes air from the smog pump into the exhaust manifolds and the catalytic converter.

 

I finally know, thanks alot!

 

get in the way and make it hard to change out plugs