I have a 99 f-150 4X4 with the triton 5.4 liter motor. I changed the plugs in the truck and realized I also had a vacuum leak. It was somewhere around the pvc and the 3 lines there were easy enough to change. Problem is I twisted of the line that runs back behind the motor and L"s and elbows into something in the manifold I guess. You cannot see it, only feel where it goes into. The big question is that the vacuum line seems to be a different size comming off the thermostat looking object than what goes onto the line I have removed. One size onto the line that runs to the three pronged pvc, and one size onto the thermostat looking object, but one vacuum line. Weird design.

Does anyone know what or where to get the vaccum line for this? Please help me if anyone has a idea of what I am trying my best to describe. Also what is the object at the rear center of the motor the vacuum line goes on too's name. It comes from the three pronged pvc line and runs behind the motor and L's back to it with a quick elbow to the coupling I guess.

Help me please as the truck only sputters now unless I hold the gas down.
Anything would be greatly appreciated at this point.

 

We also replace the "three hose PVC" line on a 2002 F-150. In our case the PVC is heated with engine coolant which accounts for two of the hoses. The third hose is the actual PVC hose which should plug into the back of the intake manifold.
Believe you can only purchase the full assembly (PVC and the three hoses w/clamps) from the locale dealer (where I found it) or cheaper at Partsguyed.com. Rockauto.com may have it also...