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A/C Compressor Pressure Relief Valve

WARNING: This page is about a different car, the 2009 Ford Mustang. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: If the A/C compressor is operating within limits and the A/C pressure relief valve is venting, or if the A/C pressure relief valve is leaking around the threads, install a new A/C pressure relief valve and O-ring. If the A/C pressure relief valve still vents after it is replaced, diagnose the refrigerant system for a restriction.

An A/C compressor pressure relief valve is incorporated in the compressor manifold and tube assembly (4.0L) or the A/C compressor (4.6L or 5.4L) to prevent damage to the A/C compressor and other system components, and to avoid total refrigerant loss by relieving unusually high refrigerant system discharge pressure buildups. For specifications regarding operating pressure(s), refer to CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS .

The A/C pressure relief valve is a separate component and can be replaced separately from the A/C compressor or compressor manifold and tube assembly. It is necessary to recover the refrigerant before removing the A/C pressure relief valve.