Air Pump Resonator
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 1995 Ford RV Cutaway, 1995 Ford Pickup, 1995 Ford F-Super Duty, 1995 Ford Econoline, and 1995 Ford Cutaway. 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.