Your secondaries aren't opening up. My friend had a Cougar where the cable that opened them was frayed in half from a pulley. (wasn't secured right at the factory) but it could be anything. Butterflies are gunked shut from all the EGR crap, servo that pulls the cable is shot, or a combination.
Take off your plastic "Duratec" cover and you'll see the servo/cable right underneath it. Inspect for damage/problems. If you can't see any you'll have to take off your intake manifold and see if there's an internal problem.