To those that have the duratec "Tick" that is loud and proud at RPM's below 2500-ish Like myself, You probably have some tired bushings in the intake for the mechinisim. Here is a video I thought that might help make sense of what is going on on.
Here is a video of the TICK :
Here is a video of the flappers:
Thought it might be some good info for someone looking. I will be replacing my intake manifold soon, I don't want those little bastards to break completely and fall inside the engine. They are little butterfly valves that operate by vacuum via the pcm. 2004+ duratecs do not have these. Either I'll replace the manifold, or try to remove the flappers (but leave the computer accessories to allow the PCM to stay happy and not throw a code)