Where is the low pressure ac port on a 1991 Nissan Stanza?

On a 1991 Nissan Stanza, the low-pressure AC port is typically located on the larger of the two AC lines that run between the compressor and the evaporator. You can usually find it near the passenger side of the engine bay, close to the firewall. It may have a blue or black cap and is generally accessible for charging or checking the system's pressure. Always ensure the engine is off and the AC system is not under pressure before attempting any maintenance.