Air Pump Resonator
WARNING: This page is about a different car, the 1995 Ford Pickup, 1995 Ford Econoline, 1995 Ford Club Wagon, and 1995 Ford Bronco. However, it is still accessible from the selected car via links, so may be relevant.
Visually inspect for holes. Remove hoses and check for restricted ports. Replace resonator if holes or ports are restricted. Reconnect hoses, and install clamps.