I found the white hose, I now realize I put it back on the wrong part of the part, lying on top of the engine today. What is this part called and what does it do? Thanks for any help you can offer me.

 

Almost looks like the fuel pressure regulator to me.

 

Which motor and year?

 

It is a 5.4 L Triton 3V on a 2006. I think I am getting it figured down to something with the heating/cooling system?

 

It looks like a vacuum line. I think some heating cooling controls are vacuum.

 

From what I could finally find it is part of the A/C circuit which allows for less coolant flow to the heater core during Max A/C operation. It helps to get more air conditioning. Whew...it was bugging me to figure this one out!

 

Heater control valve and the vacuum line is in the wrong place it goes on the nipple om the front of the valve not on top.

 

Thanks for the help.