Air Cleaner Temperature Sensor
WARNING: This page is about a different car, the 1995 Mazda B4000, 1995 Mazda B3000, and 1995 Mazda B2300. However, it is still accessible from the selected car via links, so may be relevant.
At temperatures less than 75°F (24°C), vacuum should pass through air cleaner temperature sensor. At temperatures greater than 75°F (24°C), valve should hold vacuum.