High Pressure Relief Valve
WARNING: This page is about a different car, the 1994 Mercury Grand Marquis and 1994 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.
This valve, located in compressor high side discharge line, relieves excessively high pressures. Valve opens at 450 psi (32 kg/cm2 ) to prevent damage to compressor and other A/C components. Valve closes when pressure returns to normal.