well, i did it. i installed the AFE Intake on my 4.6is.
Sonnyboy, u were correct. that extra part is/was
connected to some sort of vacuum switch. i thought
it was electronically controlled, but it's not. the hose
runs under the engine cover. i left the hose attached
under the engine and tied it off under the AFE Intake.

so far so good. i'll try and get pics this week.

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