No diagrams or pictures here, but, lots of good information.
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Which plenum-intake or. . . .
very carefully
You have to remove the intake plenum air chamber to get to the 3 plugs against the firewall. It requires to buy intake plenum gaskets and go ahead and replace the PCV hose on the back of the plenum. Need to get from the dealer. Gaskets also from dealer.
remove upper intake plenum
Try checking behind the air intake plenum. It should be a round thing.
You have to remove the intake plenum. It just unbolts.
It is 10 Nm or 89 lb-in for Isolator bolt, plenum bolts, and throttle bolt.
The plenum is the intake manifold.
The intake plenum on most cars is bolted directly atop the intake manifold. This is where the air goes after passing through the throttle body.
The intake plenum is simply the top of the upper intake manifold, where the throttle body is attached. It is made of black plastic.
Plenum is another name for the upper intake manifold.
This is one of the key symptoms of the notorious "isolator bolts" problem with many Windstar engines.There's a ton of information, including photo-how-to repairs guides available.See "Related Questions" below for more